£25,000 Audiophile Pre-Amp repair video by Mend It Mark - Page 1
Forum section: electronics / general

author: Nucleonics
author_rank: Newbie
timestamp: December 03, 2024, 11:50:13 am
content: Well looks like i'm a bit late with this post, the designer had the video taken down. Not surprisingly given the user comments about the build construction.Apparently the secret sauce, as revealed by Mark, were hand picked amp-ops that had matching characteristics (sorry i forgot which parameter it was). Loads of separate power supplies and a ton of tantalum capacitors (one of which was the source of the problem). The boards were stacked with plastic standoffs, which got knocked off during shipping.Hope it gets unblocked since it was quite interesting. Maybe it's available somewhere.EDIT: Removed video is now on Odysee:https://odysee.com/The-%C2%A325,000-Pre-Amp-that-went-Wrong---Tom-Evans-Mastergroove-SR-mkIII:c

author: themadhippy
author_rank: Super Contributor
timestamp: December 03, 2024, 12:24:10 pm
content: copyright infringement myarse. My guess is the purveyor of over price audio tat was upset that someone dared to prove him wrong and manged to fix it rather easily and without damaging the stylus,depriving him of his over priced repair fee.

author: Andy Watson
author_rank: Super Contributor
timestamp: December 03, 2024, 12:27:52 pm
content: I watched that video. It will be interesting to see if Mr Evans can make the copyright claim stick.Interesting to see what 25k audiophool pounds will buy! The tricks for reducing noise are well known - as Mark explained. The only secrret sauce was variety of op-amp used which I believe Mark only guessed at. The mechanical construction was embarrassingly flimsy, especially for something with a £25K price tag. There was obvious shielding on the top and bottom but, unless I missed something, nothing on the sides. The case appeared to be plastic.I don't think I'll be buy one of those

author: themadhippy
author_rank: Super Contributor
timestamp: December 03, 2024, 12:41:11 pm
content: QuoteThose audiophile cardboard shims dont come cheap you know

author: armandine2
author_rank: Frequent Contributor
timestamp: December 03, 2024, 12:44:08 pm
content: ..definitely glad I watched it when I had the chance to - Mark certainly gave him something to remember

author: Nominal Animal
author_rank: Super Contributor
timestamp: December 03, 2024, 11:44:13 pm
content: I can easily understand paying £2.5k for a bespoke handmade unit to ones own specifications/needs. But £25k? That's exploitation, unless it was an art piece and aninvestment. You know, like an unconnected tantalum cap superglued to the wall as an exhibit.

author: Nucleonics
author_rank: Newbie
timestamp: December 06, 2024, 07:01:32 pm
content: Mark just posted a follow-up video... given the humor included i wonder if this one will be blocked too.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 06, 2024, 07:22:08 pm
content: No way on earth there is a valid copyright claim just for showing the insides of a commercial product.Hope the complainer gets a good spanking for making a false claim, topped with good dose of Streisand effect - what a muppet!

author: madires
author_rank: Super Contributor
timestamp: December 06, 2024, 07:27:24 pm
content: Luckily I watched the video before it was taken down. I can fully understand why Mr. Evans feels embarrassed.

author: themadhippy
author_rank: Super Contributor
timestamp: December 06, 2024, 08:10:08 pm
content: Now thats what i call a follow up video

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 06, 2024, 08:42:19 pm
content: I also watched the first video about that preamp : absolutely amazing, and so well featured by Mark's natural humor.The 'ultra low noise' preamp is build by cascading several DC power supplies (some of them made with 78XX, 79XX) to raise the PSRR of the whole system.Noise floor of the preamp is improved by wiring 4 opamps in // (so noise factor is divided by 2). Again, nothing extraordinary : the trick is known for decades.Elektor published 30 years ago a phono preamp with 8 JFETS in // that can be build for 30 bucks. Anybody interested for $£€ 1 000 000 ?As mentionned above, the PCB of Mr. Evans preamp are badly stacked/cobbled together with nylon spacers as you can see here :https://hackaday.com/2024/11/14/repairing-the-questionable-25000-tom-evans-audiophile-pre-amp/And no lateral shields at all : it is well known that magnetic parasitic fields never travel horizontally.Indeed, the Streisand effect is taking place :https://www.audiosciencereview.com/forum/index.php?threads/repairing-the-questionable-%C2%A325-000-tom-evans-audiophile-pre-amp.58548/https://www.lencoheaven.net/forum/index.php?topic=45691.0https://pinkfishmedia.net/forum/threads/repairing-a-%C2%A325k-phono-stage-gulp.298363/page-5https://forums.stevehoffman.tv/threads/tom-evans-mastergroove-sr-a-25k-embarrassment.1213315/

author: thm_w
author_rank: Super Contributor
timestamp: December 06, 2024, 10:16:13 pm
content: Quote from: Andy Watson on December 03, 2024, 12:27:52 pmThe plastic case is funny, even cheap audio gear usually has spray on conductive shielding.And the true irony is that this thing is (acording to hackaday) a record player pre-amp, which means the noise levels are near irrelevant to begin with.

author: EEVblog
author_rank: Unknown
timestamp: December 06, 2024, 11:38:07 pm
content: This is exactly why I advocate that every Youtuber should be on other platforms like Odysee.There is no way for us to see the video so that we can be sure what any potential issue is.But Mike is right, it's obviously yet another abuse of the Youtube copyright system.

author: coppice
author_rank: Super Contributor
timestamp: December 06, 2024, 11:45:38 pm
content: Quote from: thm_w on December 06, 2024, 10:16:13 pmWhy would noise be irrelevant? A moving coil input is very sensitive, and they usually have some screening, to avoid pick-up from nearby things, like motors and transformers. This unit has some sheets of un-etched PCB for screening, although its pretty crudely done. I think they might not have even been grounded. In the follow up video Mark makes fun of the use of really low quality plastic spacers, rather than more robust and rigid brass ones, which would have provided a good ground path.

author: langwadt
author_rank: Super Contributor
timestamp: December 07, 2024, 12:11:25 am
content: Quote from: EEVblog on December 06, 2024, 11:38:07 pmseem to me like the only times I've remember seeing those false claims a treated correctly is when someone at google in the right place follows the channel and know which buttons to pushI guess it is cheap and safe to have a bot accept all claims and deny all counter claims

author: Xena E
author_rank: Frequent Contributor
timestamp: December 07, 2024, 12:39:16 am
content: Quote from: EEVblog on December 06, 2024, 11:38:07 pmI did see the video, it basically showed the amp as the embarasing load ofbadly madegarbage that it is.Mark didn't do or say anything wrong...The manufacturer obviously didnt want that kind of publicity. I thought the folow up video from Mark was a nice middle finger salute.X

author: thm_w
author_rank: Super Contributor
timestamp: December 07, 2024, 01:05:32 am
content: Quote from: coppice on December 06, 2024, 11:45:38 pmThe inherent noise floor of a record itself is already high ("-60 dB RIAA- and A-weighted with respect to 5 cm/s, 1 kHz"). Then on top of that you add the stylus noise, and pick up from nearby sources as you say."Tom’s shtick is that the best way to achieve true high resolution with vinyl is to lower the noise floor on the phono stage, the quieter this crucial part of the amplification chain is the wider the bandwidth and the more you will be able to hear. He advocates spending more, a lot more on the phono stage than the cartridge because no matter how good a cartridge is if the amplifier is noisy you won’t be able to hear what it’s doing."Anyway its been discussed to death already.https://www.diyaudio.com/community/threads/the-25-000-preamp-that-went-wrong-tom-evans-mastergroove.419907/

author: magic
author_rank: Super Contributor
timestamp: December 07, 2024, 08:34:41 am
content: Someone reuploaded it to Odysee:https://odysee.com/The-%C2%A325,000-Pre-Amp-that-went-Wrong---Tom-Evans-Mastergroove-SR-mkIII:cI haven't watched the whole video but the insides do look a little funny.

author: coppercone2
author_rank: Super Contributor
timestamp: December 07, 2024, 09:19:57 am
content: I have a feeling that equipment might be designated for use in EM quiet areas or housed in a shield room or something, given the price.I am not going to comment about the electronics, but the mechanical design and wiring does look shitty, even if it was made plastic for some design reason, for the price.Is it some.... attempt... for vibration or dielectric constant related design?More then likely someone got a stomach ache when they saw the cost of good standoffs and stuff lolI Guess whatever insane margin someone contrived got blown by tantalum caps and they decided to wrap it in TP.I am almost 100% certain that even if someone did manage some kind of enhanced specification on some audio related parameter, the 'systems engineering' basically destroyed it, even if its located in a anechoic cave on the moon.

author: Towger
author_rank: Super Contributor
timestamp: December 07, 2024, 03:01:16 pm
content: A great follow-up video from Mark, unlike others who rant that YouTube is always conspiring against them.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 07, 2024, 03:38:25 pm
content: Quote from: magic on December 07, 2024, 08:34:41 amThe mechanical design not only made it very flimsy but everything had to be stripped completely just to replace that one poxy tantalum tick...Mr Evans could have at least useddecenttantalum caps.If Mark didn't bill that job at 10% of new cost for the amp, He sold himself short.X

author: Bud
author_rank: Super Contributor
timestamp: December 07, 2024, 03:41:44 pm
content: I'd bill 20% minimum.

author: rsjsouza
author_rank: Super Contributor
timestamp: December 09, 2024, 03:50:58 am
content: Just watched the Odysee re-post. Great work from Mark and what a terrible assembly and choice of parts for the price.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 09, 2024, 08:25:05 am
content: Quote from: Bud on December 07, 2024, 03:41:44 pmI re watched the original video.I had completely missed the fact that the manufacturer seems to have sent the amplifier to Mark themselves with that challenge!I hope he sent it back properly packed......perhaps filling it with builders expanding foam to make it more rigid before giving it to the Evri van driver.X

author: tszaboo
author_rank: Super Contributor
timestamp: December 09, 2024, 09:35:25 am
content: Quote from: Xena E on December 09, 2024, 08:25:05 amI though it was a customer, after the manufacturer refused to repair it.I watched the video, and the construction was obviously a joke, that "shielding" is made by someone who ahs no deeper understanding of electrical fields. If you want to shield it you build it in a mu metal enclosure for starters, or at least Aluminium, not laser cut acrylic.The standoffs seems to be identical that you get from Aliexpress in a kit for 1.99 including shipping.I honestly don't know why anyone would want to own this preamp. Even before it was opened and reviewed. There is one reason, and that's consultants building a system for you, and getting paid percentage, based on how much they spend on it.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 09, 2024, 09:37:49 am
content: Quote from: tszaboo on December 09, 2024, 09:35:25 ammu-metal is for shielding magnetic fields, not electric - any metal will do for the latter

author: tszaboo
author_rank: Super Contributor
timestamp: December 09, 2024, 10:35:50 am
content: Quote from: mikeselectricstuff on December 09, 2024, 09:37:49 amYes, and for an amplifier that practically claims "lowest noise ever, better than any other amplifier" shielding magnetic fields as well as electric would be a requirement. It's not magic to have this, I have a relatively Yamaha AVR that comes in bent steel chassis. This is something done by many audio gear.You stack it on a HiFi shelf, it can pick up the magnetic field of the transformer of another amp, and it gets amplified 1000 times in a phono preamp, and you get 50Hz hum.

author: artag
author_rank: Super Contributor
timestamp: December 09, 2024, 06:58:21 pm
content: Quote from: Xena E on December 09, 2024, 08:25:05 amYeah, what was that about ? Couldn't he fix it himself ? Was he trying to show Mark up with a 'difficult' repair ? Why would he do that to a genuinely nice bloke ? It was a tant shorting a power line FFS.. Mark put far more effort into documenting the amp properly than he did fixing it, which he took minutes over once he'd documented it.

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 09, 2024, 07:03:27 pm
content: Quote from: Xena E on December 09, 2024, 08:25:05 amWhen I heard this, I couldn't believe it.Does this mean Mr. Evans is incapable of repairing his lovingly-cobbled-together stuff himself?Did he actually outsource the design and manufacturing?

author: themadhippy
author_rank: Super Contributor
timestamp: December 09, 2024, 07:39:31 pm
content: could be the owner was quoted £6k for the repair by tom evans,and when they declined they were pointed towards mark who wouldnt be able to repair it

author: temperance
author_rank: Super Contributor
timestamp: December 09, 2024, 08:00:03 pm
content: Quote from: themadhippy on December 09, 2024, 07:39:31 pm

author: BrianHG
author_rank: Super Contributor
timestamp: December 09, 2024, 08:02:40 pm
content: If I were to make a super quiet phono pre-amp, I would make the first gain stage differential right on the RCA input connector itself cased in a copper tube, powered by a photo voltaic cell (basically acts like a combination supply and constant DC current source) being most likely a custom discrete differential bipolar transistor design. The photo-voltaic making this stage completely separate from the mains with differential output for the next stage. This is the place where you need to take care of the noise on the massive gain needed for a MC phono cartridge.The later stages could be generic high quality op-amps and instead of the stupid power supplies, just a properly designed high current ultra low ripple DC regulated supply with properly LC filtered sub-division if necessary.The 30k$ for what was illustrated was a joke.

author: EEVblog
author_rank: Unknown
timestamp: December 09, 2024, 09:39:41 pm
content: I just noticed that at 13:19 he does show the actual schematic from what is presumably the service manual in a spiral binder.So maybe, technically, he does have a copyright claim for that bit if the service manual is proprietary? Although it's not marked as such, at least on the page he shows.

author: themadhippy
author_rank: Super Contributor
timestamp: December 09, 2024, 09:47:40 pm
content: Quoteyou mean the service manual mark produced himself ?

author: Andy Watson
author_rank: Super Contributor
timestamp: December 09, 2024, 09:50:10 pm
content: Quote from: EEVblog on December 09, 2024, 09:39:41 pmIf I remember correctly, Mark reverse-engineered the unit to make that "service manual". The circuits displayed were very similar to what might be found on the chip datasheets.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 09, 2024, 09:59:10 pm
content: Mark showed his own reverse engineered document, and some semi manufacturer's application notes.TBF to Mr Evans the amp used pretty competent noise reduction techniques in the design, but not the mechanical construction... and it was built down to such a low standard that even an Amstrad looks better quality beside it... I think it's niether here nor there how much the ticket price was, it just looks like a crappy prototype lash up...I bet it picks up mobile phone interference like buggery.

author: Bud
author_rank: Super Contributor
timestamp: December 09, 2024, 10:00:13 pm
content: Quote from: BrianHG on December 09, 2024, 08:02:40 pmNude virgins need to be paid. And delivery from the remote island is expensive.

author: langwadt
author_rank: Super Contributor
timestamp: December 09, 2024, 10:00:27 pm
content: Quote from: EEVblog on December 09, 2024, 09:39:41 pmthe page has a "Mend It Mark" logo on the footer, I assume he drew himself

author: Xena E
author_rank: Frequent Contributor
timestamp: December 09, 2024, 10:03:14 pm
content: Quote from: themadhippy on December 09, 2024, 07:39:31 pmMark said at 20 seconds in on his second video that the unit was sent him directly by the manufacturer.What arrogance to then claim he wouldnt be able to fix it!

author: Gyro
author_rank: Super Contributor
timestamp: December 09, 2024, 10:24:52 pm
content: Just a thought that it might have been a stunt to get some visibility of his 'advanced' design and manufacturing techniques (or artisan hand building), similar to a certain robot builder, only to have his balloon burst by Royal Mail, his plastic pillars and a healthy dose of reality. The unexpected result might then have prompted him to have the subsequent video taken down.Yes it's an oddball thought, but it's also pretty arrogant for the manufacturer to send a faulty unit to a repair channel with such a challenge without expecting the internals to be seen (he can'treallyhave expected Mark not to figure out the concealed fixings under the foot pads?).

author: wraper
author_rank: Unknown
timestamp: December 09, 2024, 10:42:07 pm
content: What a piece of junk. I doubt I'd pay even $10 for that garbage to flip it afterwards because I'd feel shame for selling such piece of shit at all.

author: themadhippy
author_rank: Super Contributor
timestamp: December 09, 2024, 11:05:39 pm
content: QuoteHe does,but he didnt say he had been asked to repair it by the manufacturer.maybe marks client had it shipped directly from tom evans after balking at a £6k repair price

author: Xena E
author_rank: Frequent Contributor
timestamp: December 09, 2024, 11:36:12 pm
content: Quote from: themadhippy on December 09, 2024, 11:05:39 pmThat would make more sense... but either way it all just seems so bizarre.X

author: magic
author_rank: Super Contributor
timestamp: December 09, 2024, 11:56:47 pm
content: Quote from: wraper on December 09, 2024, 10:42:07 pmThere is more than $10 in there in tantalum caps alone.Semiconductors too, but you would need to decap a few to identify them.I'd take it for $10

author: EEVblog
author_rank: Unknown
timestamp: December 10, 2024, 12:45:46 am
content: Quote from: Andy Watson on December 09, 2024, 09:50:10 pmAh, so it is, I stand corrected.

author: showman
author_rank: Contributor
timestamp: December 10, 2024, 01:27:37 am
content: Looks like Louis Rossmann will reupload the video to his channel and will fight for it to not be removed again.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: December 10, 2024, 02:11:38 am
content: The mechanical design is not robust, certainly not Post Office proof, and there are many things to be questioned in the electrical design. But at least it does have decently low noise as shown in Marks final test sequences.The copyright violation may be subtle. In Mark's reverse engineered documentation package he appears to use the manufacturers name in the title block, stand alone in a separate box. I am not a member of the legal profession but this may be unauthorized use. I think it would have been better if he said something like "Reverse engineered approximation to product of ...."

author: showman
author_rank: Contributor
timestamp: December 10, 2024, 02:46:09 am
content: Quote from: CatalinaWOW on December 10, 2024, 02:11:38 amI don't see how this has anything to do with copyright. Perhaps you mean trademark, which it might have something to do with, but I doubt it as well.

author: EEVblog
author_rank: Unknown
timestamp: December 10, 2024, 03:23:12 am
content: Quote from: showman on December 10, 2024, 02:46:09 amYes, nothing to do with copyright. Using a Trademarked name or logo for identification purposes has been well established in trademark case law, so almost certianly not an issue. Although as is always the case in trademark law, the deepest pocket destroys the shallowest pocket.

author: 5U4GB
author_rank: Super Contributor
timestamp: December 10, 2024, 03:51:24 am
content: Quote from: Nominal Animal on December 03, 2024, 11:44:13 pmAs long as you duct-tape a banana next to it you should be fine.

author: themadhippy
author_rank: Super Contributor
timestamp: December 10, 2024, 03:56:36 am
content: No idea if this is genuine, if it is ,it has a dodgy grape smell to meQuote

author: coppercone2
author_rank: Super Contributor
timestamp: December 10, 2024, 04:28:36 am
content: Quote from: Bud on December 09, 2024, 10:00:13 pmlaying pipe is always expensive (shielded input)

author: Xena E
author_rank: Frequent Contributor
timestamp: December 10, 2024, 05:47:44 am
content: Quote from: themadhippy on December 10, 2024, 03:56:36 amYou could wrap that turd up and transport it how you like, but a good shake would fuck it up without internal support.Whatever, it's a pile of crap.X

author: magic
author_rank: Super Contributor
timestamp: December 10, 2024, 07:01:00 am
content: Quote from: themadhippy on December 10, 2024, 03:56:36 amIf it's fake, it's written by somebody who understands the mentality of "those people" well, or at least has similar prejudices to mineIt took me 40 years to design thisyou have no idea what goes into itit's got professional grade capacitors, manthe ICs were all hand pickedI would replace the whole board to be sureAnd obligatory:QuoteActually, I wonder if this last one might be true at all. Wasn't it simply a rail bypass cap? It shouldn't be damaged by the signal path.But he may have a point regarding the 7815 which was feeding this shorted capacitor.Another thing I'm curious about is if this reg is actually a critical part, perhaps something depends on its voltage exactly matching the 7915?QuoteThis would imply that there was more to the story than Mark said.

author: tszaboo
author_rank: Super Contributor
timestamp: December 10, 2024, 10:32:40 am
content: Quote from: themadhippy on December 10, 2024, 03:56:36 amYes, kindergarten level name calling is real classy, it will make sure that everyone will side with you, because you don't come off as a total douchebag. /sAlso, professional grade tantalums... As opposed to what, consumer tantalums?And magical remote debugging of ICs? You can tell that it's faulty, because what, you have a statistics on your total 80 units sold that it always happens.

author: armandine2
author_rank: Frequent Contributor
timestamp: December 10, 2024, 10:37:12 am
content: --- hope this doesn't go Wagatha Christie on ushttps://en.wikipedia.org/wiki/Wagatha_Christie

author: DenCraw
author_rank: Contributor
timestamp: December 10, 2024, 11:32:39 am
content: Wow! 40 years reading the same application note from BurrBrown!.https://archive.org/details/manuallib-id-2650324/page/8/mode/2up?q=OPA111BTW; it seems that somebody wants this video forever!.https://archive.org/details/the-gbp-25-000-pre-amp-that-went-wrong-tom-evans-mastergroove-sr-mk-iii-rjbp-fsfzi-i

author: BrianHG
author_rank: Super Contributor
timestamp: December 10, 2024, 01:40:22 pm
content: Quote from: magic on December 10, 2024, 07:01:00 amAfter 40 years of engineering, if you truly need a matched negative supply, aren't you supposed to design a tracking regulator from a single reference, not use cheaply binned 7815s and 7915s which may temp drift and age differently?

author: Xena E
author_rank: Frequent Contributor
timestamp: December 10, 2024, 02:39:30 pm
content: Quote from: tszaboo on December 10, 2024, 10:32:40 amWhat I'd say are professional grade are the tubular metal cased variety, not those resin dipped leftovers from the 1970s. They were a joke even then.X

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 10, 2024, 02:48:21 pm
content: tough cap.

author: madires
author_rank: Super Contributor
timestamp: December 10, 2024, 04:26:03 pm
content: Quote from: themadhippy on December 10, 2024, 03:56:36 amLooks like Tom booked the super deluxe Streisand effect experience package. He didn't refute asking 6k for the repair and told us that he gets 10k per unit. Also considering the build quality, it's clear that his side of the story is just a smoke screen to hide what he is selling for 10k. Mark's video simply revealed the reality, i.e. what's inside the box.

author: coppice
author_rank: Super Contributor
timestamp: December 11, 2024, 02:44:42 am
content: Quote from: tszaboo on December 10, 2024, 10:32:40 amConsumer grade (bead type) and professional/military grade (sealed cylindrical) tantalum capacitors are very different. The tubular ones are truly sealed, rarely suffer corrosion issues, and will operate for decades at 125C in military applications. We used to use them in telecoms systems, like telephone exchanges, too. Their problem in occasionally a whisker grows between the plates, and shorts the thing out. In supply decoupling applications the power supply normally fuses this whisker, and everything seems OK afterwards. However, the momentary short makes most digital systems crash. So, telephone exchanges hiccuped every now and then, which lead to the discovery of this phenomenon. Around this time Philips and a couple of others launched the first dry electrolytics, and we migrated to those for telecoms. I was out of defence work by then, so I don't know if they followed the same path.

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 11, 2024, 08:06:15 am
content: Thanks Dave. This new video from Louis brings interesting information.Louis reads Marks' email. At 1:57 we can hear : "The preamp was originally sent to the manufacturer by its owner but it got damaged in the post. They quoted the owner some ridiculous repair price. I think it may have been around £6,000 but I can't find any evidence but it was certainly several thousand Pounds. The owner was not happy to pay that so instructed the manufacturer to ship it to me for repair despite warning the owner I would not be able to fix it. So the preamp was shipped to me from the manufacturer but not that they needed me to do the work".Some takeaways about that :1) The buzzing (electronic circuit failure) and the broken enclosure happened independently of each other.2) The explanation that @themadhippy could find earlier and that might (or not) be the manufacturer's point of view, plainly contains some inexact information, like : "It was him ( 'bodge it Mark') that posted the unit to us".Quote from: themadhippy on December 10, 2024, 03:56:36 am3) Louis is ready for a huge legal fightStay tuned!

author: tszaboo
author_rank: Super Contributor
timestamp: December 11, 2024, 02:41:56 pm
content: Quote from: coppice on December 11, 2024, 02:44:42 amWell the point is that in the past 15 years, consumer products moved away from tantalum capacitors for multitude of reasons. It's a conflict material, more expensive, performance is outclassed. The consumer grade tantalum capacitor market is all but dead.Saying that "I used professional grade tantalum" is a statement that's empty. It's the equivalent that you used automotive grade transistors. So it's the same transistor, but it goes to 125C and the supply chain is checked regularly, congratulations. It goes into a consumer equipment, and it's not used at high temperature anyway. Lifetime is not correlated with the grade. It's not better or worse QC wise, and likely to come from the same production line with different marking.There will be actually better tantalums, wet with extra small leakage or hermetically sealed or whatever. But it's the same through hole green frog from the 80s, that's a fire hazard with a exothermic failure rate orders of magnitude more often than an elco. Quite embarrassing in a new design to be honest.

author: EEVblog
author_rank: Unknown
timestamp: December 12, 2024, 09:25:05 am
content: Quote from: timeandfrequency on December 11, 2024, 08:06:15 amDetails irrelevant when it comes to the copyright takedown.

author: Kleinstein
author_rank: Super Contributor
timestamp: December 12, 2024, 11:50:16 am
content: For the copyright question they could claim that the amplifier is a 3D work of art. In this case pictures of the object could still be copyrighted by the maker.Still I think this is a bit far fetched and stetching the rules.

author: EEVblog
author_rank: Unknown
timestamp: December 13, 2024, 03:09:02 am
content: Quote from: Kleinstein on December 12, 2024, 11:50:16 amNot a chance. Fair Use case law alone makes this not a thing.

author: andy3055
author_rank: Super Contributor
timestamp: December 13, 2024, 08:50:01 pm
content: So, Mark's video is back on line. However, it is on a channel by NickT6630

author: EEVblog
author_rank: Unknown
timestamp: December 13, 2024, 11:56:18 pm
content: Video is up on Trevor's Bench channel. Louis hasn't uploaded on his channel yet.

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 13, 2024, 11:57:09 pm
content: The video can also be found on the 'Twobob Club' channel.It duplicates itselfAt the beginning one channel was buzzing, now the whole preamp creates buzz.

author: EEVblog
author_rank: Unknown
timestamp: December 14, 2024, 12:07:33 am
content: More uploads!

author: Xena E
author_rank: Frequent Contributor
timestamp: December 14, 2024, 12:08:35 am
content: Quote from: timeandfrequency on December 13, 2024, 11:57:09 pmCertainly has.The Mend it Mark Channel has had quite a number of extra subscribers over this too.X

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 14, 2024, 12:15:46 am
content: And two more uploads on channels 'Brettbob Brettbob' and '84johnhead'Maybe CNN will broadcast it soonQuote from: Xena E on December 14, 2024, 12:08:35 amYes, about 20 k more since he published the first video of the broken preamp.

author: BrianHG
author_rank: Super Contributor
timestamp: December 14, 2024, 05:24:13 am
content: Quote from: EEVblog on December 11, 2024, 06:26:18 am@3:55, Can someone please explain to me why everyone misunderstands what a patent is.No, if the circuit design was patented, just showing a copy of said patented schematic cannot get you in trouble or get a website or video taken down for illustrating said patent's documentation.Having a patent means your invention's design and schematic is available to the public for review and anyone can share said patented documents. Otherwise, Google Patent's who has copied the US PTO database would be illegal and the US PTO (other countries included) would not have their patents available for search and review to the public.The only thing having a patent gives you the right to sue someone for monetary damage if they produced a copy of your patented invention where they made a profit from said sales, or they prevented you from selling your invention. It must be proven in court that said monetary damages have taken place before you can claim damages from the infringing party for a calculated amount of funds. You may also send a cease and desist notice.A little less known, is you are manufacturing your own patented gizmo, you must place a copy of your patent number somewhere on your device, otherwise, you may loose your protection rights to that device. This is why almost all patented devices or even patented software have all their patented numbers written down easily accessible by the end user.

author: EEVblog
author_rank: Unknown
timestamp: December 14, 2024, 07:56:42 am
content: Quote from: BrianHG on December 14, 2024, 05:24:13 amIt's worse. You can't patent a schematic. try it and watch the patent attoney laugh in your face.You can patent how part of a circuit works, but not the actual schematic in how it's drawn. And certainly not the entire product schematic.The exact schematic is what copyright is for.So if say Apple produced and internal schematic and someone photocopied that and shared it, that would be copyright infringement.But if you reverse engineer and redraw the schematic, that is not copyright infringemnet. Very clear case law here.

author: magic
author_rank: Super Contributor
timestamp: December 14, 2024, 10:13:16 am
content: Hello,This is Tom Evans here. Please delete this thread immediatelyQuote from: BrianHG on December 14, 2024, 05:24:13 amIs it really the case? I mean, Microsoft patented some parts of FAT32 filesystem. Where can everyone see the notification about it?

author: coppice
author_rank: Super Contributor
timestamp: December 14, 2024, 10:24:22 am
content: Quote from: BrianHG on December 14, 2024, 05:24:13 amThat used to be the case, and older products often had a long list of patent numbers on them, typically moulded into a plastic part so they wouldn't easily wear off. However, I think this requirement was dropped some years ago, at least in most countries. You certainly don't see those patent number lists like you used to.

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 14, 2024, 11:06:25 am
content: To summarize (updated on 20241216)Mend It Mark [first video]The £25,000 Pre Amp that went Wrong Tom Evans Mastergroove SR mkIII[URL placeholder, video was taken down due to 'copyright' claim]Mend It Mark [second video]The £25,000 Pre-Amp Repair and the Copyright Strikehttps://www.youtube.com/watch?v=yPIrCaeVtvI (edit URL to remove space characters)Article from HackadayAuthor : Maya PoschLouis RossmannTom Evans audio proves that their $30,000 audio preamp is garbage by filing a bogus copyright claimhttps://www.youtube.com/watch?v=gJYIhLQJtTs (edit URL to remove space characters)https://odysee.com/@rossmanngroup:a/tom-evans-audio-proves-that-their-30,000:1Louis RossmannTom Evans Audio doubles down on a bad decisionhttps://www.youtube.com/watch?v=qYpPNCzQCVQ (edit URL to remove space characters)https://odysee.com/@rossmanngroup:a/tom-evans-audio-doubles-down-on-a-bad:3Louis Rossmann (added on 20241216)Mastergroove repair by Mend it Mark & an honest message to Tom Evans audio (upload of Mark's first video + 5 min 20 sec foreword from Louis) (39 k views)https://www.youtube.com/watch?v=6hVe_spuJQI (edit URL to remove space characters)https://odysee.com/@rossmanngroup:a/mastergroove-repair-by-mend-it-mark-an:1Many other YT channels uploaded Mark's first video (mainly low res)- On Odysee (7 k views) Account name : 'Anonyme'https://odysee.com/The-%C2%A325,000-Pre-Amp-that-went-Wrong---Tom-Evans-Mastergroove-SR-mkIII- NickT6630 (41 k views)[20241215 : 61 k views !][20241216 : 78 k views !]https://www.youtube.com/watch?v=uJ35ufUh2Tw (edit URL to remove space characters)- 'Brettbob Brettbob'- '84johnhead'- 'M0UAW' (20241216 : 5.7 k views)- 'GTI1dasOriginal'- 'Trevor's Bench'(6,8 k views)[20241216 : 10 k views]-'matt moran'(Update 20241215 : video has been removed from this channel)- 'Stephen McGregor'- 'Mr.HatnBootz'- 'MVVblogTV'- 'Norbert2' (3 incomplete uploads)- 'Mateusz Petryszyn'- 'Twobob Club'(13 k views)[20241216 : 16 k views]- 'David McGinn'- 'Marten Electric'- 'Turntable Guy'[hint : to locate Mark's first video on the channels above, use the YT search feature on the channel page and type 'Mend It Mark' or 'Tom Evans']Other stuff about the same topic- 'Martin Piper' reactionhttps://www.youtube.com/watch?v=vFcHGAs2QLQ (edit URL to remove space characters)- Funny rant from 'Audio Masterclass'https://www.youtube.com/watch?v=93QlQN_1yUA (edit URL to remove space characters)- New video from 'Audio Masterclass'https://www.youtube.com/watch?v=XWIdMjG-TCU (edit URL to remove space characters)- Scott's (Defpom's Electronics Repair) reactionhttps://www.youtube.com/watch?v=15AiQv-EiGM (edit URL to remove space characters)Date format used in this post is YYYYMMDD (ISO 8601)*** Post history ***Update #1 : typoUpdate #2 : added the 'Twobob Club' channelUpdate #3 (20241215) : added the 'David McGinn' and 'Marten Electric' channels, added a hint how to find the video, typo in Odysee URL, added Odysee URL for Louis videos, added some view counts, new video from 'Audio Masterclass'Update #4 (20241216) : added 'Turntable Guy' and 'Louis Rossmann' channels, added video from Defpom, updated some view counts

author: DenCraw
author_rank: Contributor
timestamp: December 14, 2024, 01:42:33 pm
content: ... and the schematics?..... just kidding

author: BrianHG
author_rank: Super Contributor
timestamp: December 14, 2024, 06:38:35 pm
content: Quote from: magic on December 14, 2024, 10:13:16 amNote that for software, the patents only need to be listed somewhere inside some document connected with the software. Example, on Altera's Quartus, on the about page, they have a mass of patents which are listed.Also note that if you do not intend to protect your patent, or make the patented tech available for public use, or the patent has expired, its obvious that you may not bother listing the patent number anymore.The last time I was told to add a patent number on a device was in the mid-late 90s. As of today, I do not know if the rule has changed, but I do know if you intend to protect your patent rights, you still need to offer a means of giving those seeking if your technology is patented with your patent number. IE: you cannot hide that your tech is patented as a surprise gotcha for your competitors.

author: rsjsouza
author_rank: Super Contributor
timestamp: December 15, 2024, 12:34:43 pm
content: Just a lighthearted comment about this whole situation on another audio-oriented channel.

author: BrianHG
author_rank: Super Contributor
timestamp: December 15, 2024, 04:19:48 pm
content: Quote from: EEVblog on December 14, 2024, 07:56:42 amActually, technically, you can patent a schematic, however, it is a fruitless endeavor.All a competitor needs to do is alter, add or remove a single resistor or capacitor value and they are no longer infringing on your patented schematic.So, you need to patent the end concept and function of you design so that no one may create a similar functional device.

author: BrianHG
author_rank: Super Contributor
timestamp: December 15, 2024, 04:25:58 pm
content: Quote from: EEVblog on December 09, 2024, 05:56:59 amLouis missed the buck on this one. Others have already uploaded copies of the video and have yet to be taken down. As stated in his second video on the subject, he is doing other things in the mean time before uploading this video to his channel next week, a week before X-mas. The instant retaliatory hit will now be gone and nothing will be seen or happen until after new years at this point which may be so long in time, even the pre-amp manufacturer may have given up on copyright striking at this point.

author: coppice
author_rank: Super Contributor
timestamp: December 15, 2024, 05:04:00 pm
content: Quote from: BrianHG on December 15, 2024, 04:19:48 pmYou can't actually patent a schematic. You can use a schematic in a patent, and then describe the bit that makes it novel. Its that definition of the novelty which is the actual patented thing. Copied exactly as in the schematic, or executed in another way deemed to be applying the same technique, gets you in trouble. Copying the rest of the schematic doesn't. The schematic is just supporting material.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 15, 2024, 06:23:01 pm
content: So this is still a hot topic?The complaint was copyright infringement.To copyright a schematic, (at least in the UK, which is applicable here), you must publish that schematic in the public domain, and clearly mark each diagram as being subject to copyright.Now that doesn’t protect the device from being cloned by others, it just gives you sole rights to thatexactpiece of literature, diagram, or artwork.Now as Tom Evans Audio has never it seems publicly published a service manual for the Mastergroove pre-amp, not even as a for sale document, the secrecy no doubt to cover up the fact that there was nothing unique or patentable about the design in the first place.That document could then reasonably be argued to be the copyright of the Mend it Mark YouTube channel as the first published schematic of the design: as such I'd personally make those reverse engineered drawings available online, and claim copyright for myself,if it were me, just to flip the bird at Tom EvansIt seems copyright of electronic schematics doesn't impress anyone, except the spineless mutts in charge of youtube.I will make a prediction that Tom Evans Audio won't be suing anyone, for anything. No legal entity would risk their reputation on trying to pursue this in a court of law,unless Tom Evans Audio has enough dough to finance a nuisance law suit which if their annual returns are anything to go by, they haven't.X

author: coppice
author_rank: Super Contributor
timestamp: December 15, 2024, 06:29:47 pm
content: Quote from: Xena E on December 15, 2024, 06:23:01 pmEven that is legally very weak. There is a reason they passed special copyright legislation for chip masks, and introduced the "M" symbol you see on chips. People found the existing copyright laws didn't actually protect what is essentially a schematic drawn on silicon. The laws that specifically protect a mask set don't give any additional protection to any other form of schematic.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 15, 2024, 06:48:01 pm
content: Quote from: coppice on December 15, 2024, 06:29:47 pmYes.The copyright laws are archaic, they were only really intended to protect authors of written works from plagiarism in the first instance.Basically you have to copy the content verbatim to be in any real danger of litigation.X

author: coppice
author_rank: Super Contributor
timestamp: December 15, 2024, 06:54:53 pm
content: Quote from: Xena E on December 15, 2024, 06:48:01 pmOne of the early things that copyright laws were specifically developed to protect were maps, and naval charts, which are not a million miles in nature from a modern schematic. Still, somehow, those laws don't work for a schematic.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 15, 2024, 07:50:16 pm
content: There again, it would require that the infringment were a verbatim copy, and the defendant had directly benefited.In the case of a schematic or a nautical map this would be the same. Fair use of the schematic would be to use the information to repair the relevant equipment as in Mark's case.Fair use of a nautical map would be navigation.Unfair use and copyright infringement would only extend to verbatim copying of the published work for gain, for example sale of the circuit diagram directly, or the map for others to use in navigation.It can and has been argued that images on the internet can constitute infringement, but only if it is verbatim, in full, and for financial advantage.Very difficult to case prove however.The most usual copyright litigation cases these days must IMHO be that of music and video entertainment.X

author: artag
author_rank: Super Contributor
timestamp: December 15, 2024, 08:04:47 pm
content: Comparing a schematic with a map is particularly relevant since it clearly isn't reasonable to copyright the source, which is the natural environment. Whether a developer could copyright the arrangement of roads in a development is perhaps more feasible but I rather doubt would be permitted.

author: EEVblog
author_rank: Unknown
timestamp: December 15, 2024, 09:20:55 pm
content: Quote from: Xena E on December 15, 2024, 06:23:01 pmYou don't have to publish something in the public domain to hold copyright.If a company produces a schematic internally for company use and someone makes a direct copy of that and publishes it, the person who copied it is going to lose that copyright case very quickly.And anyone who distributes it (say a forum like this one) and does not remove it when requested, will also lose any legal fight very easily.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 15, 2024, 10:39:59 pm
content: Quote from: EEVblog on December 15, 2024, 09:20:55 pmThe devil is in the detail there.If Tom Evans has produced a service manual that Mark had stolen and illegally distributed for personal gain, then yes, Mark gets taken to the cleaners.But firstly he has to prove he holds the prior art and then that he has claimed copyright for it.It could mean formally publishing it and offering it for sale, or making it freely available for fair use.For instance, a book.Alternatively it could be notarised as being intellectual property, though in that case it would not be possible to claim damages against someone who could prove independent development of the same work if the original were kept secret.And it would have to be identical.It is then the burden of the plaintiff to prove that it was stolen. Reverse engineering a commercial product, particularly one that has no patents applicable to it, is not theft.It's no good producing the document after the fact with some half baked claim that you did it first.It is so much more easily proven that, say, a music video has been copied and uploaded illegally.In any case, in this instance Evans claimed woo woo futuristic technology for something that was known art, and has not yet produced any copyright material to substantiate his claim against Mark. (And he can't if he has not registered the material which isn't possible as Mark created it himself!)This is about Evans bullying a creator on You Tube who augments his income from his repair business by producing interesting and informative content, theres a lot of shit on there that needs deleting before any videos that Mark has produced.If Evans takes this any further, (ie., successfully sues anyone), I'll eat your sweaty daks!(Opinions my own, and not those of EEVBLOG)X

author: EEVblog
author_rank: Unknown
timestamp: December 16, 2024, 12:29:14 am
content: The full letter from Tom:https://www.maverick-hifi.com/post/repair-of-%C2%A325000-phono-stage-that-tom-evans-said-couldnt-be-done-13527150?trail=40QuoteBut issuing a copyright strike?Sound like he's basically admitting he's doing this to proect his "reputation", and not his copyright (which obviously was not violated anyway).

author: Halcyon
author_rank: Unknown
timestamp: December 16, 2024, 01:43:26 am
content: Quote from: EEVblog on December 16, 2024, 12:29:14 amI also love the bit where he says opening the case voids manufacturer's warranty. That's not true at all, even in the US I believe. Same with "unauthorised repair" clauses; Those aren't enforceable either (at least here in AU). Anyone with the appropriate skills can repair a device without impacting it's warranty. Same reason why not having your vehicle serviced by the manufacturer or dealer generally won't void the manufacturer's warranty.However, if you break something, or do something wrong, that's entirely on you then.

author: BrianHG
author_rank: Super Contributor
timestamp: December 16, 2024, 02:01:44 am
content: Quote from: coppice on December 15, 2024, 05:04:00 pmYou would have to precisely describe your schematic in words as your claims at the end of your patent. However, you also must prove no one have ever done something similar in the past and what your are doing is truly novel. Again, a patent like this is useless. The rest of your comments are correct practice.This is why I said, technically, it is possible to do so, but you will never see it in practice.Very early on in patents, like the invention of the first stapler or paper 3 hole punch, or a mechanical valve for a steam engine, the claims may have specifically described the mechanical schematics of the illustrations, however, today, the more likely claims cover the innovative concept itself as locking down an entire concept field is where you truly gain monetary value from your patent.The best hope is to be granted a grandfather patent in a new field or business where you become the sole dominator for 18 years.

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 16, 2024, 05:13:00 am
content: Quote from: EEVblog on December 16, 2024, 12:29:14 amThe letter written by Tom Evans and reproduced by member 'Paullongcase' on the 'Maverick hifi forum' is the same that @themadhippy already posted on this thread recently (reply #51).So nothing new about that. So does the riddle about who sent the preamp in a basic card box. As you said @Dave, the latter information is "irrelevant when it comes to the copyright takedown".Actually, as you underscored, Tom Evans' whole letter does not provide any serious argument regarding copyright infringement.Tom Evans just seems upset and jealous because he couldn't charge the owner of the preamp a few thousands Pounds for this repair. A wise professional that sells such expensive gear (including almost 'alien technology') who wants to promote his image of excellency would have done the repair quite for free, even after the end of the warranty period. This is exactly what some well-known manufacturers with a well-established reputation do.Mark did the repair successfully, by following his usual way : he just replaced the parts that were broken and showed (as usual, I would say) extensive skills on how to repair the enclosure without having original spare parts. Was Tom Evans so naive to expect that Mark would need to buy him some genuine spare parts?Mark's goal was clear : repair the preamp at minimal cost. He succeeded. And the preamp owner must be pretty happy about that.Update #1Rather than applaud Mark for his good work, Tom Evans chose to ask YT to take down the preamp repair video.As a side effect and due to the Streisand effect, he's currenty damaging his own reputation.From here, I hear the aliens laughing.

author: EEVblog
author_rank: Unknown
timestamp: December 16, 2024, 09:52:46 am
content: Louis put the video up:

author: Zero999
author_rank: Super Contributor
timestamp: December 16, 2024, 10:37:40 am
content: Quote from: timeandfrequency on December 16, 2024, 05:13:00 amI'm no lawyer, but I believe that under UK consumer protection law, Tom Evans would have been obligated to repair the amplifier for free, irrespective of the warranty, given the extortionate price of the product.Assuming that letter is genuine, he comes across as a petulant child who's been caught with their pants down.I question the legality of selling such a 💩 for that price. An arguement could me made that it's fraud.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 16, 2024, 10:45:54 am
content: Quote from: Zero999 on December 16, 2024, 10:37:40 amPrice has no bearing on warranty cover.It's only fraud if it claims to be something it isn't - a £25k preamp is still a preamp - it's up to the customer to decide if it's worth the price to them.

author: magic
author_rank: Super Contributor
timestamp: December 16, 2024, 10:59:46 am
content: That's news to me too, although I reserve some skepticism and refuse to automatically reject the possibility of such nonsense actually being real - it's government after all

author: Zero999
author_rank: Super Contributor
timestamp: December 16, 2024, 12:49:48 pm
content: Quote from: mikeselectricstuff on December 16, 2024, 10:45:54 amThe manufacture warranty doesn't affect your statutory rights. Even if it has expired, then you're still protected by the law, which mentions price and durability. In other words, one should expect a £25 000 a pre-amp to last a heck of a lot longer than a £25 pre-amp.Quote from: Consumer Rights Act 2015, Section 9https://www.legislation.gov.uk/ukpga/2015/15/section/9QuoteI don't know about what claims were made, hence why chose my language carefully, so as not to make any false accusations.Quote from: Zero999 on December 16, 2024, 10:37:40 amI think it's a fair question to ask, given the build quality vs price.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 16, 2024, 04:08:15 pm
content: Quote from: Zero999 on December 16, 2024, 10:37:40 amUndoubtedly it is a very poorly constructed item, but the principles of its design, at least from the point of view of the signal path and the noise reduction techniques are valid, the overly complex power supply I doubt its value. But I'm not an audiophile: I like to listen to the music, not the equipment.I really wonder how much, technically better it is than the 1960's Mullard designed preamplifier/equaliser that is in my turntable, that has I think, just four BC109s in the signal path...very little I'd guess.I can tell the difference between 10% THD+Nand 1%, but buggered if I can tell the difference between 1% and 0.1%...As for price, nobody is being forced to buy it in the first place, but yes I'd say a lifetime guarantee for the original purchaser would be perfectly reasonable minimum for the unit... and would have gained Evans some kudos and positive customer satisfaction that would have reinforced his reputation, not destroyed it.X

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: December 16, 2024, 04:58:38 pm
content: Quote from: Xena E on December 16, 2024, 04:08:15 pmYou think like an engineer, but you write like an ....phile, you are factually hearing your equipment and it affects drastically the reproduced music.

author: andy3055
author_rank: Super Contributor
timestamp: December 16, 2024, 05:42:37 pm
content: "I really wonder how much, technically better it is than the 1960's Mullard designed preamplifier/equaliser that is in my turntable, that has I think, just four BC109s in the signal path...very little I'd guess..."There is a vast improvement in components from that time to the present which contribute to the sound quality and signal to noice ratio etc. That is not a factor in this case anyway because it applies to even the cheap but modern gear made by anyone. It is entirely up to the designer of the circuitry to make it happen using "primier" parts. Even then, how much is it going to cost to make those few boards given the low priced but good components anyone can aquire at present?If there are suckers to buy at those prices because they have nothing better to do with their money, well then, make hay while the Sun shines.It is said that the cell phones are more powerful than the computers used by NASA during the Appolo program. So, let him make a black box with a cell phone inside and sell it to NASA for a few millions! Will NASA go for it?

author: coppice
author_rank: Super Contributor
timestamp: December 16, 2024, 05:59:08 pm
content: Quote from: Xena E on December 16, 2024, 04:08:15 pmIt may or may not be far better than your 1960s design, but that isn't really relevant. You can get a fantastic SNR these days, for very little money. That would stop hiss when the stylus is up, but does that matter when the SNR of a record is quite poor when the stylus is down? A simple late 60s moving magnet phono pre-amp had pretty much got to the point of being better than the records it reproduced combined with the best cartridges. Moving coil cartridges have a lower output, and it took a few more years before a simple pre-amp had sufficient SNR to not influence the output which playing a record. We are still only talking about the early 70s, though.

author: Zero999
author_rank: Super Contributor
timestamp: December 16, 2024, 06:03:08 pm
content: The physical construction is part of the design. Flimsy mechanical construction aside, the use of tantalum capacitors is a poor design choice. There are superior parts available there's no excuse not to use them, given the product's extortionate price.The audio amplifier was solved many decades ago. Yes, there's always some room for improvement, but it's beyond the point of diminishing returns, as it's impossible to hear the difference between decent quality amplifiers.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 16, 2024, 07:19:44 pm
content: Yeah.Things have been improved to the point of superlatives but anyone who say they can hear the difference between the very good and claimed perfection where they are listening through the surface noise of a vinyl record are talking absolute bollocks.The basic principles of the Mastergroove can be implemented in a product that is both better made and better value.People buying the mastergroove are just buying a dream. They are buying bragging rights to owning a rarity, If they had the slightest idea about how such equipment should be engineered and packaged, they wouldn't buy that. Evans even built a transparent cased version, plastic stand offs, tant ticks the lot, all on full show to the world, and it still sold!You've got to admire the person who has the balls to pull that off.X

author: Zero999
author_rank: Super Contributor
timestamp: December 16, 2024, 07:25:48 pm
content: Quote from: magic on December 16, 2024, 10:59:46 amPresumably you're commenting on my reply mentioning UK consumer law.Why is it nonsense? If you buy something cheap, then you shouldn't expect it to last as something you've paid a lot of money for. It makes perfect sense the law takes this into account. A 1 year warranty (I don't know what the warranty on this item is, but that's often the default) on such an expensive product is just unreasonable.Quote from: Coordonnée_chromatique on December 16, 2024, 04:58:38 pmIf the equipment is properly designed and is working properly (guitar amplifiers/effects boxes aside) then the equipment shouldn't drastically affect the reproduced music.

author: coppice
author_rank: Super Contributor
timestamp: December 16, 2024, 07:55:31 pm
content: Quote from: Xena E on December 16, 2024, 07:19:44 pmIf you have never been to a high end audio show, where this kind of stuff is sold, try one. Its an interesting experience. There can be some amazing stuff at those places, but the amazing stuff is almost exclusively speakers. In 2024 fairly inexpensive electronics can drive those really nice speakers as well as anything. Take a look at the crazy amps. Massive things, at crazy prices, made of the cheapest materials. You might think they would use aluminium for something expensive, but no. You need to observe the behaviour of the attendees when the vendor opens up one of these things to show the interior. They are impressed by the kilo. The heavier the equipment is, the more impressed they are. So a vendor struggling to lift a thick steel lid off an amp gets a wow from the audience that an aluminium lid would not.

author: Stringwinder
author_rank: Contributor
timestamp: December 16, 2024, 08:12:11 pm
content: I have never seen a design that totally misses the "do's & don'ts" to get mechanicalreliability like this one does. Instead it could be used as an example of how not to buildelectronics. If you pay ridiculous amounts of money you could also expect things toarrive in good working order. This amplifier has flaws with a very weak design combinedwith structures that encourage resonances and resulting high forces exactly at its weakestpoints (not to mention the choise of the materials used).I have experience from vibration testing of many types of products from simple consumerelectronics up to actual "rocket science" (a few G up to ~3000 G). Putting boards onthin plastic stilts is ridiculous. A simple low G-level sine sweep (sideways) will makeit fall/fail like a card-house when the stilts break.

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: December 16, 2024, 08:13:17 pm
content: Immaging few milliseconds that a pair of JBL K2 S9800 sound not different than a pair of cheap loudspeakers is simply amazing stupid... because both are well designed.

author: Zero999
author_rank: Super Contributor
timestamp: December 16, 2024, 09:10:56 pm
content: Quote from: Coordonnée_chromatique on December 16, 2024, 08:13:17 pmYou're now going off topic and shifting the goal posts. This thread is about amplifiers, not speakers.Speakers do affect the sound quality, much more than any amplifier, but there's no need to spend silly money. Room acoustics are also important, even more so than decent speakers. If your room echos, then it can create distortion, as the reflected sound interferes with that produced by the speakers and it'll sound bad, irrespective of how much money you've wasted on them.

author: coppice
author_rank: Super Contributor
timestamp: December 16, 2024, 10:05:30 pm
content: Quote from: Zero999 on December 16, 2024, 09:10:56 pmThese were silly money, but if you ever heard them you might realise silly money can buy you something interesting in speakers.http://www.infinity-classics.de/models/IRS-series+Beta+Gamma-Delta-Sigma-Epsilon-1988-95-98/IRS/IRS2.jpg

author: Halcyon
author_rank: Unknown
timestamp: December 16, 2024, 10:46:19 pm
content: Quote from: mikeselectricstuff on December 16, 2024, 10:45:54 amWhen it comes to consumer law, price is a component of it. Warranty and legislative guarantees are two different things.It comes down to whether a product is "reasonably durable". If you spend $25k on a piece of fairly basic audio equipment, a reasonable person would expect it to last quite a number of years (I'd suggest 10+ years). If it were a $25 product, a year might be more reasonable.That being said, these types of audiophool products go against the "you get what you pay for" notion. Whilst they might work, at those kinds of prices, it's starting to be more of a scam than anything else.

author: magic
author_rank: Super Contributor
timestamp: December 16, 2024, 11:02:19 pm
content: Quote from: Halcyon on December 16, 2024, 10:46:19 pmThey don't. You pay for a feeling that you own something unique and better than the rest, and no one can take that from you until some asshole publishes a teardown on YouTube.Delete it, damnit!

author: CatalinaWOW
author_rank: Super Contributor
timestamp: December 16, 2024, 11:47:27 pm
content: Quote from: Stringwinder on December 16, 2024, 08:12:11 pmWell the designer doesn't buy your argument, and goes all in by cantilevering heavy components on thin plastic stilts. Probably has some mumbo jumbo about lowering mechanical resonances a decade or more below audible frequencies thus eliminating acousto-magnetic coupling for an exceptionally deep sound with fine clear defined edges on mid-frquencies.

author: BrianHG
author_rank: Super Contributor
timestamp: December 16, 2024, 11:55:46 pm
content: This audiophile pre-amp design / construction is more inline with its price being 1/5th the other one:(And guess what, this manufacturer did not send MIM a copyright take-down notice...)

author: rsjsouza
author_rank: Super Contributor
timestamp: December 17, 2024, 01:14:00 am
content: Quote from: Zero999 on December 16, 2024, 07:25:48 pmZero999, I understand this is the law of the land, but that is the kind of B.S. law that leaves to interpretation something that should be clearly stated in a warranty card or any other terms and conditions of the sale. The way it is, any disputes will require the intervention of the justice system, which is discouraging ($$$) for a great deal of cases.If there is a clear warranty statement on the product or in the pre-sales material, it should left to the buyer the decison to pay so much for such puny warranty.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 17, 2024, 01:18:36 am
content: Quote from: coppice on December 16, 2024, 07:55:31 pmNo need. Ive spoken to Russ Andrews on a dare several years ago.The challenge was to speak to him for ten minutes without my swearing at him, (I have a form of tourettes syndrome, I'm not just a potty mouth).Got a lifetimes supply of audiophool bullshit there.Guy actually told me that he occasionaly went to live music performances to, and I quote here:"Recalibrate my ears."https://www.russandrews.com/To be fair to Russ Andrews, I will say that unlike the subject of the thread, Russ Andrews Accessories give a money back guarantee on all their products and I believe 25 year guarantee...The gear is also well made...Would I buy any of it?Hell no!X

author: themadhippy
author_rank: Super Contributor
timestamp: December 17, 2024, 01:21:31 am
content: Quoteso have i,all be it for about 30 seconds before he ran off and hid

author: Xena E
author_rank: Frequent Contributor
timestamp: December 17, 2024, 02:03:44 am
content: Quote from: themadhippy on December 17, 2024, 01:21:31 amBully!

author: coppice
author_rank: Super Contributor
timestamp: December 17, 2024, 02:47:57 am
content: Quote from: Xena E on December 17, 2024, 01:18:36 amThat's the producer side. They seem to be a mix of bullshitters and true believers. Its the consumer side which is more interesting.

author: Monkeh
author_rank: Super Contributor
timestamp: December 17, 2024, 03:07:14 am
content: Quote from: rsjsouza on December 17, 2024, 01:14:00 amThe mere threat of someone exercising their rights will, in most cases, gain compliance with reasonable demands without the need for legal intervention.QuoteReal-world effect: The buyer will have no choice but to accept the bare minimum terms offered by the manufacturers, because they won't offer you anything they don't have to. Oh, but you can buy additional insurance which will have at least twenty ways to deny your claim for only another 15% of the purchase price!

author: hpssb
author_rank: Contributor
timestamp: December 17, 2024, 06:02:20 am
content: Quote from: Xena E on December 17, 2024, 01:18:36 amIt would want it to be "well made" for the price, $1700 aussie for an audiophile grade IEC mains cable

author: andy3055
author_rank: Super Contributor
timestamp: December 17, 2024, 06:41:16 am
content: Here is a great clip which Tom Evans should see:

author: magic
author_rank: Super Contributor
timestamp: December 17, 2024, 08:05:52 am
content: Quote from: Monkeh on December 17, 2024, 03:07:14 amSomehow reminds me of this

author: Halcyon
author_rank: Unknown
timestamp: December 17, 2024, 08:40:30 am
content: Quote from: hpssb on December 17, 2024, 06:02:20 amInteresting how they sell UK, US and Euro plugs, but not Australian/New Zealand versions? I wonder why that is.Also for an extra 200 pounds, you can get "Process Q™". Woooooo.

author: Zero999
author_rank: Super Contributor
timestamp: December 17, 2024, 09:37:04 am
content: Quote from: rsjsouza on December 17, 2024, 01:14:00 amI only posted one section of the law. It does specify time periods, for rejecting the goods, repairs etc. just not a fixed warranty period. It stops manufacutres from doing shady things such as designing products which fail just outside the warranty period.

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 17, 2024, 09:45:51 am
content: $449(off topic. sorry.)

author: Xena E
author_rank: Frequent Contributor
timestamp: December 17, 2024, 05:53:29 pm
content: Quote from: hpssb on December 17, 2024, 06:02:20 amI didn't mention value for money. I did say I wouldnt buy it...People who believe in all this old hokum are the ones that are going to get fleeced... and they deserve it.But if you get a money back guarantee if it doesn't work as you expect, then nobody can complain... can they?As for the price... call for your 90% discountIt's all bollocks. The anti RFI kit that gets sold is usually defeated by a 2g phone. If you stand outside the shop when they're demonstrating some of their high end equipment it pisses them right off.Once the tat is bought and paid for, I think the emperor won't return his new suit for a refund, because he has to then admit he was duped in the first instance.It's clever marketing.X

author: coppice
author_rank: Super Contributor
timestamp: December 17, 2024, 05:58:07 pm
content: Quote from: hpssb on December 17, 2024, 06:02:20 amThat's a bargain. I've seen similar cables selling for over 4000 pounds. That one is 3m long. I think the 4000 pound ones were only 2m, so this one is even better value.

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: December 17, 2024, 06:11:30 pm
content: Quote from: Zero999 on December 16, 2024, 09:10:56 pmI'm sorry, thanks for your answer.But, the electronics are intergated in the audio appliances today... who sill buy a separate preamplifier in 2024Even anold fartas me integrates a ready made AMP/DSP in its DIY loudspeakers.

author: Zero999
author_rank: Super Contributor
timestamp: December 17, 2024, 06:30:45 pm
content: Quote from: Coordonnée_chromatique on December 17, 2024, 06:11:30 pmYes, integrating an amplifier into the speakers is a good, because it's easy to add a filter/signal processing to correct for the frequency response and phase shift of the speakers, but this thread is about a stand alone preamplifier.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 18, 2024, 11:21:25 pm
content: Now ifixit joins the pile-on ...

author: EEVblog
author_rank: Unknown
timestamp: December 19, 2024, 02:19:31 am
content: Imagine being Tom Evans now sitting there realising how badly you screwed up.

author: BrianHG
author_rank: Super Contributor
timestamp: December 19, 2024, 03:50:38 am
content: Quote from: EEVblog on December 19, 2024, 02:19:31 am1. On one hand, it will be nerve racking.2. But then next he will come to the understanding that his clientele don't watch youtube repair videos.(I give it a day of relief.)3. Then he will realize how stupid his blunder was realizing if he just shut up, no one at all would ever know.(This will be worse than my point #1, now he will have to hold his hopes on my point #2, otherwise, I don't think he will sell 10 of these per year anymore.)

author: rsjsouza
author_rank: Super Contributor
timestamp: December 19, 2024, 12:03:54 pm
content: Quote from: EEVblog on December 19, 2024, 02:19:31 amQuote from: BrianHG on December 19, 2024, 03:50:38 amThat or a great deal of audiophiles will excuse the poor price/workmanship ratio as I have seen in some of the fora around the internet.Quote from: BrianHG on December 19, 2024, 03:50:38 amIf he overcomes the blindness that was triggered by his initial reaction to the video and the criticisms to his workmanship, he might re-tool with better products. On the other hand, we all have seen so many others that simply go hiding for a couple of years and then return to the same practices by a simple re-branding.

author: pope
author_rank: Frequent Contributor
timestamp: December 19, 2024, 12:12:44 pm
content: Quote from: hpssb on December 17, 2024, 06:02:20 amYou really have to match it with the correct fuse to experience the full potential.

author: Halcyon
author_rank: Unknown
timestamp: December 19, 2024, 12:26:51 pm
content: Quote from: EEVblog on December 19, 2024, 02:19:31 amDon't worry. Tom Evans can re-invent his scam products under a new name: Tim Owens.

author: Stringwinder
author_rank: Contributor
timestamp: December 19, 2024, 12:28:14 pm
content: Now the audiophiles can be amazed too!https://audiokarma.org/forums/index.php?threads/the-tom-evans-vs-mend-it-mark-shitstorm-is-great.1075383/post-17515085

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 19, 2024, 05:59:21 pm
content: Quote from: Stringwinder on December 19, 2024, 12:28:14 pmThe link seems to be dead.I found this one on the same forum :https://audiokarma.org/forums/index.php?threads/tom-evans-groove-plus-phono-stage.477761/#post-17515677

author: Xena E
author_rank: Frequent Contributor
timestamp: December 19, 2024, 06:48:15 pm
content: Quote from: pope on December 19, 2024, 12:12:44 pmThey make a real difference... to your bank balance.I'll bet the people who came up with the directional quantum science fuses is having a propper laugh at the gullible rubes that they have suckered in.The mastergroove preamp in the mean time is now offered at £12,500Let me know when its £12-50X

author: langwadt
author_rank: Super Contributor
timestamp: December 19, 2024, 06:59:08 pm
content: that kind nonsense sounds like a great way to do money laundering

author: Zero999
author_rank: Super Contributor
timestamp: December 19, 2024, 07:02:07 pm
content: Quote from: timeandfrequency on December 19, 2024, 05:59:21 pmThe other link wasn't dead when I clicked on it 10 hours ago. Perhaps Evans has influence on autiokarma.org?

author: Gyro
author_rank: Super Contributor
timestamp: December 19, 2024, 07:18:06 pm
content: Taken down fortalking aboutcopyright infringement?

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 19, 2024, 07:34:44 pm
content: Quote from: Gyro on December 19, 2024, 07:18:06 pmIf it goes on like this, Tom Evans will take down the entire Internet^^

author: BrianHG
author_rank: Super Contributor
timestamp: December 19, 2024, 07:39:04 pm
content: Quote from: timeandfrequency on December 19, 2024, 07:34:44 pmI guess Tom is going down the dig your hole as deep as possible route.

author: Zero999
author_rank: Super Contributor
timestamp: December 19, 2024, 08:22:34 pm
content: I would love to see Dave's reaction, if he told him to delete these threads.

author: SolderSucker
author_rank: Regular Contributor
timestamp: December 19, 2024, 09:36:11 pm
content: There's some new info about all of this on Mark's Patreon Page (this info can be viewed with the FREE membership option on Mark's Patreon). Mark has been approached by a journalist from Heise.de ("News and forums on computers, IT, science, media and politics. Price comparison of hardware and software as well as downloads at Heise Medien.").Firstly though, read the info that is allegedly from Tom Evans on page 3 of this thread, second message down, this message:https://www.eevblog.com/forum/other-blog-specific/25-000-audiophile-pre-amp-repair-video-by-mend-it-mark/msg5742219/#msg5742219With that in mind about what Tom Evans states regarding the method of delivery, the packaging and the state of the amp, plus Mark sending the Pre-amp to Tom Evans, etc, now read Mark's Patreon post.My very brief summary of the info in Mark's Patreon post regarding the postage/shipping is that basically the Pre-amp was INITIALLY sent to Mark by mistake - the owner had intended to send it to Tom Evans but there were two labels on the parcel, the larger one addressed to Tom and a smaller shipping label with Mark's address on it (I am assuming that Mark had maybe sent his customer a repair in the past and the customer used the old packaging without removing the old label first?). Parcel Force decided to refer to the smaller label addressed to Mark and so deliver it to him, presumably as it had a barcode on it. There are photos and more details on Mark's Patreon page:https://www.patreon.com/c/MendItMark/homeThere's also a transcript of a chat between Mark and his customer, the customer sent Mark a new label to ship the Pre-amp on to Tom Evans. After that of course the customer requested that Tom Evans send the Pre-amp to Mark for repair, as we know from Mark's repair video for the amp.Should the customer have addressed the parcel more clearly? Apparently so.Should the customer have sent it to Tom (accidentally reaching Mark instead) via a courier instead of Parcel Force? Apparently so.Should the customer have wrapped the Pre-amp a lot more carefully?Based on the message from Tom Evans, apparently so.When the new label was sent to Mark from the customer to send the Pre-amp on to Tom Evans it's not mentioned which shipping service was used but we would have toassumeParcel Force/Royal Mail, hence why Tom Evans mentions that Mark allegedly shipped the parcel via the local post office. Mark did this because that's the label the customer sent him according to the chat transcript.So there have been some errors by some parties but, from what I can tellfrom Mark's info, he is most certainly NOT at fault here and he didn't do anything wrong AT ALL, didn't even make a mistake. He didn't even know what was in the parcel when he sent it onto Tom Evans!But as I've said, read all of the info and see the label photos and customer chat transcript image on Mark's Patreon page:https://www.patreon.com/c/MendItMark/postsAll of this diverts from the takedown of Mark's repair video and points the finger at Mark for matters other than the repair, nevertheless it too needs addressing and ALL of the facts stated.We need to remember that the video takedown, etc is what is key here and what has driven people's attention towards the video and its many copies.

author: Stringwinder
author_rank: Contributor
timestamp: December 19, 2024, 10:03:59 pm
content: Don't worry - he won't get away with trying to clean up the mess he orchestrated all on his own.The very renowned forum Audio Science Review has a critical thread that just now has 222 posts.https://www.audiosciencereview.com/forum/index.php?threads/repairing-the-questionable-%C2%A325-000-tom-evans-audiophile-pre-amp.58548/post-2138955The earlier link that went dead contained a link to the YT video that started it all.The link above is just critical opinions (without any video links) that totally obliterates allthe reputation he might have had before the Mend It Mark video appeared. He won't beable to polish and clean away embarrassing facts there.Audio Science Review is engineering and fact centered and as a test and measurement engineer Ifeel at home there. I use "medium end" audio stuff but get facts about room equalization, acousticsand test equipment there. No "Boule Sheet" discussions at all.edit - sprelling errörs

author: BrianHG
author_rank: Super Contributor
timestamp: December 19, 2024, 10:10:17 pm
content: Quote from: SolderSucker on December 19, 2024, 09:36:11 pmHmmm... I don't know. Even if I was a multi-billionaire, I would still not send a 30k$ piece of electronics through regular post without real shipping insurance. Though, at that income bracket, I wouldn't be the one personally shipping the device as others would be doing all the labor for me and they would be smart enough to realize that this device should be insured when sipping.

author: coppice
author_rank: Super Contributor
timestamp: December 19, 2024, 10:14:05 pm
content: Quote from: BrianHG on December 19, 2024, 10:10:17 pmShipping insurance? What a very American response. Most Europeans would have invested in more substantial packaging.

author: SolderSucker
author_rank: Regular Contributor
timestamp: December 19, 2024, 10:34:55 pm
content: There's one ray of sunshine in all of this - Mark's subscriber count keeps climbing, he's gained 10K subs since yesterday and even more since this all started. I hope he's going to thank Tom Evans for all of the free publicity.

author: Stringwinder
author_rank: Contributor
timestamp: December 19, 2024, 10:55:44 pm
content: The mechanical design is so bad that carrying by hand on a soft eider-down pillowis the only safe way of transportation. The stilts for the PCB's are very narrow andvery high with the mass on top so a mild whack with a hand on the side of the amp willbreak them. A few millimeters wide and much longer (like 60 mm in total) will amplifyany sideway loads until the plastic cracks. Width 6 mm, screw 2 mm in the center leavesa L-shaped fulcrum with a 60/2 force increase on soft plastic. Either the threads in theplastic will strip or the stilt cracks. The swedish word "klämlängd" (that I don't knowthe engelska translation of) is what every designer MUST know. Long levers makes smallforces BIG.... but it worked on the lab bench!Now you ruined it transporting this gold-plated design!

author: themadhippy
author_rank: Super Contributor
timestamp: December 19, 2024, 11:03:29 pm
content: see the cardboard shims have made another guest appearance in marks latest video,wonder if they'll become a regular contributor.

author: BrianHG
author_rank: Super Contributor
timestamp: December 19, 2024, 11:22:27 pm
content: Quote from: themadhippy on December 19, 2024, 11:03:29 pmHis latest video was a repair of a 'MOST Broken' Sinclair Spectrum+2, where are the shims?

author: themadhippy
author_rank: Super Contributor
timestamp: December 19, 2024, 11:37:09 pm
content: Quote24:22

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 19, 2024, 11:38:59 pm
content: Quote from: BrianHG on December 19, 2024, 11:22:27 pm24:22

author: magic
author_rank: Super Contributor
timestamp: December 19, 2024, 11:52:01 pm
content: Quote from: Stringwinder on December 19, 2024, 10:03:59 pmTHD+Nphools are audiophools too.So Amir can't see any connection between a shorted rail capacitor and possibly blown ICs, in a devices which consists in 90% of voltage regulators, preregulators and postregulators?

author: thm_w
author_rank: Super Contributor
timestamp: December 20, 2024, 12:49:07 am
content: Quote from: magic on December 19, 2024, 11:52:01 pmeh, thats equivalent to saying voltnuts are fools. Or essentially any area of a hobby focused on fractional gains. We all know the benefit is minimal.At least they are chasing after real world measurable results.

author: SolderSucker
author_rank: Regular Contributor
timestamp: December 20, 2024, 07:54:24 am
content: Quote from: Simmed on December 20, 2024, 05:35:57 amIt was initially sent to Mark by mistake (by his customer) due to there being two address labels on the parcel and Parcel Force referring to the wrong one (not their fault to be honest), hence Mark initially receiving the Pre-amp when it was supposed to go straight from the customer to Tom Evans.It's fully detailed in Mark's free Patreon post.

author: magic
author_rank: Super Contributor
timestamp: December 20, 2024, 08:15:37 am
content: Quote from: thm_w on December 20, 2024, 12:49:07 amI don't think there are many voltnut-minded members at ASR. Most of them are in it for the "better sound" like cablephools, and just like them they have convinced themselves that their measurements matter, whether they actually hear anything or not.The fact that Amir rants about "science" and "objectivity" and then writes things like "it sounds completely transparent to me, based on a sighted listening test performed after taking measurements" is rather ironic. For all we know, his Golden Ears™ might well be worth as much as those of any run-of-the-mill cablephool, but he sure talks about them a lot.I don't recall him ever bothering to actually demonstrate any ability to tell 0.00001% from 0.001% or 0.1% or 10% or anything. I think it could be entertaining to make him do a blind test with one of his favorite THD+Nphool amps against Tom Evans, a random AliExpress special or even some half-decent valve contraption. Maybe he thinks so too and that's why he never attempts such demonstrations.Besides, that's not his point. As an audio salesman, he is more interested in making you buy "high end" gear than finding whether you actually need it.And it gets better, because Amir isn't then only THD+Nphool of course. I recall one TomChr who manufacturers THD+Nphool amplifiers himself and is quite vocal on ASR and other forums about them sounding better than other solid state amplifiers. Of course none of his "science" is actually backed by any strict subjective testing, he just listened to a couple of amplifiers and heared differences. Like a cablephool.

author: SolderSucker
author_rank: Regular Contributor
timestamp: December 20, 2024, 10:34:17 am
content: It's kinda fun typing Tom Evans into YouTube's search bar because most of the results feature Mark and people rightly defending Mark.

author: 5U4GB
author_rank: Super Contributor
timestamp: December 20, 2024, 10:48:26 am
content: Quote from: Stringwinder on December 19, 2024, 10:55:44 pmCan you attempt a translation? A word that sounds like someone pushing a shopping trolley down a flight of concrete steps really needs to be inserted into a conversation somewhere.

author: Xena E
author_rank: Frequent Contributor
timestamp: December 20, 2024, 11:36:58 am
content: Quote from: 5U4GB on December 20, 2024, 10:48:26 amLiterally "clamp length" I think in this context meaning mechanical amplification, or increase of mechanical advantage or force?X

author: langwadt
author_rank: Super Contributor
timestamp: December 20, 2024, 12:02:21 pm
content: Quote from: Xena E on December 20, 2024, 11:36:58 amhttps://www.nord-lock.com/sv-se/inblick/skruvsakrings-tips/2017/tips-och-rad-sa-optimerar-du-skruvforbandet-med-ratt-klamlangd/

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 20, 2024, 12:44:06 pm
content: Quote from: SolderSucker on December 20, 2024, 10:34:17 amFor Tom, that's just how to become a YT celebrity without posting any video^^

author: SolderSucker
author_rank: Regular Contributor
timestamp: December 20, 2024, 02:17:51 pm
content: Quote from: timeandfrequency on December 20, 2024, 12:44:06 pmHah, true! Although I don't think that Tom Evans has any celebrity status right now, at least not of the positive kind. On the other hand his actions have certainly drawn Mark to more people's attention and raised HIS already very good credibility even further.

author: themadhippy
author_rank: Super Contributor
timestamp: December 20, 2024, 03:56:46 pm
content: Quotereading around various forums etc it would appear his only claim to fame is taking others work and passing it off as his own .

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 20, 2024, 08:13:21 pm
content: Quote from: SolderSucker on December 20, 2024, 02:17:51 pmYes : Mark raked in about +32 k subscribers since he posted the video that was taken down.

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: December 20, 2024, 08:39:31 pm
content: Could you tell what an EE think of this kind of preamplifier please ?A more elaborated scam ?https://www.thetadigital.com/generationviii/https://tmraudio.com/components/d-a-converters/theta-digital-generation-viii-s3-dac-d-a-converter-remote-24-192-upgrade/#mz-expanded-view-218174910527

author: thm_w
author_rank: Super Contributor
timestamp: December 20, 2024, 09:53:38 pm
content: Quote from: magic on December 20, 2024, 08:15:37 amThats a bit of a different argument, IMO, just the regular meaningless audiophile speak.QuoteI don't think you need to demonstrate it, its a number on a screen.But it would still be entertaining to see yes, In reality its something like 3% distortion before you can actually notice it:https://www.axiomaudio.com/blog/distortionso 1/10th of that would be good enough.

author: coppice
author_rank: Super Contributor
timestamp: December 20, 2024, 09:57:22 pm
content: Quote from: Coordonnée_chromatique on December 20, 2024, 08:39:31 pmIn terms of value for money, there is quite a lot in there, so for a small volume product $10k is not an entirely stupid price. I expect its post office tolerance is far superior to the Master Groove pre-amp, for less than half the price, so that's a plus. Whether it offers any useful performance is another matter. It says is uses pairs of 24 bit ladder DACs. These are rather bogus products. I very much doubt they have made their own silicon, and if a 24 bit ladder DAC is built from a bunch of chips its very difficult to stabilise their temperatures well enough that the various chips track each other sufficiently well, even if you ovenize them. At one point the big silicon vendors tried making 24 bit ladder ICs, but matching problems killed them off.I believe the original Theta goes back to the early days of CDs when most CD sound quality was quite poor, due to the performance of affordable early 80s DACs. However, the world has moved on. The results people like AKM achieve these days with cheap audio ADC and DAC chips is quite impressive.

author: magic
author_rank: Super Contributor
timestamp: December 20, 2024, 10:05:02 pm
content: Quote from: thm_w on December 20, 2024, 09:53:38 pmIMO a more "scientific" forum than ASR is Hydrogen Audio, wheremasochipeople actually sit for hours listening to various things and produce rankings of codecs by perceived quality and things like that.Playing with an audio analyzer is something anyone can do, particularly if one doesn't even care about high quality results. One thing that bothered me last time I looked at ASR (admittedly, a few years ago) was that no tests were done at various volume knob positions, which is known to affect noise (Johnson) and also distortion of bipolar input amplifiers. It wouldn't be hard to design an amp which works perfectly at 100% volume and unity gain at 2V RMS (or any other input level) but totally falls apart at -6dB volume - just use a 1MΩ volume pot and a high bias bipolar input stage, done.

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 21, 2024, 11:56:39 am
content: To summarize (updated on 20241228)Previous release of this post isreply #71that was updated on 20241216.Mend It Mark [first video]The £25,000 Pre Amp that went Wrong Tom Evans Mastergroove SR mkIII (43:52)[URL placeholder, video was taken down due to 'copyright' claim]Mend It Mark [second video]The £25,000 Pre-Amp Repair and the Copyright Strike (4:17291 k views)https://www.youtube.com/watch?v=yPIrCaeVtvI (edit URL to remove space characters)Article from HackadayAuthor : Maya PoschLouis RossmannTom Evans audio proves that their $30,000 audio preamp is garbage by filing a bogus copyright claimhttps://www.youtube.com/watch?v=gJYIhLQJtTs (edit URL to remove space characters) (18:47384 k view)https://odysee.com/@rossmanngroup:a/tom-evans-audio-proves-that-their-30,000:1Louis RossmannTom Evans Audio doubles down on a bad decisionhttps://www.youtube.com/watch?v=qYpPNCzQCVQ (edit URL to remove space characters) (6:64257 k view)https://odysee.com/@rossmanngroup:a/tom-evans-audio-doubles-down-on-a-bad:3Louis RossmannMastergroove repair by Mend it Mark & an honest message to Tom Evans audio (upload of Mark's first video + 5 min 20 sec foreword from Louis)https://www.youtube.com/watch?v=6hVe_spuJQI (edit URL to remove space characters) (49:1839 k189 k views)https://odysee.com/@rossmanngroup:a/mastergroove-repair-by-mend-it-mark-an:1iFixitMastergroove Repair by Mend It Mark Because Repair Information Should Be Free (45:10 25 k view)https://www.youtube.com/watch?v=KOuetLQgM4w (edit URL to remove space characters)Many other YT channels uploaded Mark's first video (mainly low res)Greetings toNickT6630who also searches and lists all this stuff (see the comments below his copy of Marks's video.- On Odysee Account name : 'Anonyme'https://odysee.com/The-%C2%A325,000-Pre-Amp-that-went-Wrong---Tom-Evans-Mastergroove-SR-mkIII(8.4 k views)- NickT6630 (41 k views)[20241215 : 61 k views !](20241216 : 78 k views !)(103 k views)https://www.youtube.com/watch?v=uJ35ufUh2Tw (edit URL to remove space characters)- 'Brettbob Brettbob'- '84johnhead'- 'M0UAW'(20241216 : 5.7 k views)(14 k views)- 'GTI1dasOriginal' (2.5 k views)- 'Trevor's Bench'(6,8 k views)[20241216 : 10 k views](22 k views)-'matt moran'(update 20241215 : video has been removed from this channel)- 'Stephen McGregor' (1,7 k views)- 'Mr.HatnBootz' (3k views)- 'MVVblogTV' (1,7 k views)- 'Norbert2' (3 incomplete uploads)- 'Mateusz Petryszyn'- 'Twobob Club'(13 k views)[20241216 : 16 k views](20 k views)- 'David McGinn' (2.3 k views)- 'Marten Electric' (2.7 k views)- 'Turntable Guy' (4.4 k views)- 'Sort it out man'- 'Matt'- 'alch3myau'- 'aitor co'- 'Rhine-Labs'- 'Als_25_Phototographer'- 'Gotan's Basement'- 'Ckunak' (upload of Louis' video)- 'Pete'- 'Cristian Negrea'- 'Lagittaja'- 'Jakob Varming' (5.7 k views)- 'Haxorflakes'- 'Ralfy Customs' (1.2 k views)- 'S P'- 'BaconButtie' (upload of Louis' video)- 'Dogextreme'- 'Julian'- 'michael daniel'- 'RepairIT'- 'levendlicht'- 'marcel'- 'granddad19921' (upload on the 'Internet Archive')- 'zzwijnands'- 'nanocamp audio'- 'Rumi'- 'CookieClassiC Keks'- 'Lagittaja'- 'ShR33k'- 'Als_25_Phototographer'- 'alch3myau'Hint : to locate Mark's first video on the channels above, use the YT search feature on the channel page and type 'Mend It Mark' or 'Tom Evans'Other stuff about the same topic- 'Martin Piper' reaction (8:27 56 k view)https://www.youtube.com/watch?v=vFcHGAs2QLQ (edit URL to remove space characters)- Funny rant from 'Audio Masterclass' (8:53 45 k views)https://www.youtube.com/watch?v=93QlQN_1yUA (edit URL to remove space characters)- New video from 'Audio Masterclass' (4:40 28 k views)https://www.youtube.com/watch?v=XWIdMjG-TCU (edit URL to remove space characters)- 3rd video from 'Audio Masterclass' (13:13 39 k views)https://www.youtube.com/watch?v=_VIXbYmf1Lo (edit URL to remove space characters)- Scott's (Defpom's Electronics Repair) reaction (8:50 29 k views)https://www.youtube.com/watch?v=15AiQv-EiGM (edit URL to remove space characters)- Scientific Audiophile (excerpt about the video takedown)The Shock of 2024 - Audiophile Edition- 'fellpower' reaction (25:22 native language : german ; english subtitle translation available)https://www.youtube.com/watch?v=3XJPEKze5rg (edit URL to remove space characters)- Audio Science Review (ASR) ForumRepairing The Questionable £25,000 Tom Evans Audiophile Pre-Amp- 'VE99 Online' reaction (native language : german ; english subtitle translation available) (link provided by @madires, thanks to him)https://www.youtube.com/watch?v=Nl8ooDSFHv8&t=220s (edit URL to remove space characters)- Case analysis made by copyright attorney Leonard French (video was found by @SolderSucker, thanks to him)https://www.youtube.com/watch?v=8WMi4cBMbIs (edit URL to remove space characters)- 'Code Therapy w/ René Rebe' reaction (16:45 7.6 k views)https://www.youtube.com/live/sHc9_E0w9P0 (edit URL to remove space characters)Date format used in this post is YYYYMMDD (ISO 8601)*** Post history ***Update #1 20241221 : added 'Audio Science Review (ASR) Forum' and video upload on the 'Internet Archive'Update #2 20241228 : added 'VE99 Online' reaction, case analysis made by copyright attorney Leonard French 3rd video from 'Audio Masterclass' and 'Code Therapy w/ René Rebe' ; added 'zzwijnands','nanocamp audio', 'Rumi', 'CookieClassiC Keks', 'Lagittaja', 'ShR33k', 'Als_25_Phototographer' and 'alch3myau' links

author: Stringwinder
author_rank: Contributor
timestamp: December 21, 2024, 01:45:30 pm
content: It seems like Tom Evans is very sensitive to interference from the "outside".Takedown notices have had the opposite effect.His brainchild also suffers from another sensitivity to interference but of the EMI-kind.I can't imagine any takedown notices will fix that. Maxwells Laws are still valid everywhere.- "Stop using RF emitters here or I will take legal action!"The design (EMI-wise) is the worst I have seen in many years.I don't suffer from Audiophoolia Nervosa so I will leave it at that.My hobby is to make lots of noise (on old acoustic instruments), no electronicsat all and only a few grams of metal involved.God Jul!

author: coppice
author_rank: Super Contributor
timestamp: December 21, 2024, 03:14:22 pm
content: Quote from: Stringwinder on December 21, 2024, 01:45:30 pm"No publicity is bad publicity" - B Streisand.

author: pope
author_rank: Frequent Contributor
timestamp: December 21, 2024, 06:29:15 pm
content: Quote from: coppice on December 21, 2024, 03:14:22 pmWithin reason I would assume.

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: December 23, 2024, 07:58:21 pm
content: Quote from: coppice on December 20, 2024, 09:57:22 pmThe selled performances are technically unattainable,... don't you think that 10K€ is enough for a functional product ?

author: r6502
author_rank: Regular Contributor
timestamp: December 25, 2024, 10:10:03 am
content: Hello all,interesting what goes on here.I found also photos, where the housing is made from transparent acrylic plates, may be you saw it, but I did no saw a link here, may be it is interesting:https://community.naimaudio.com/t/tom-evans-mastergroove/34491/5Interesting, that they sell an expensive equipment like this preamp with a transparent housing. My first projects looked similar from the inside - very handcrafted. If you are paying that much money for your stuff, you will hear the difference...From my side nothing more to sayGuido

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 25, 2024, 10:14:27 am
content: I would be too embarrassed to use a transparent case.

author: coppercone2
author_rank: Super Contributor
timestamp: December 25, 2024, 05:12:23 pm
content: for the money it should have ITO coating and some RF fingers at least if it must be transparentthat might actually make it a unique product that does something new lolThere also exist fine RF screens that you can put on less visible parts to make it more shielded. They are pretty much see through like nylons.The novel sales point being that it manages to have performance approaching a shoddy enclosure but its mostly transparent. And its not cheap materials so you can charge for that.https://diamondcoatings.com/hard-coated-acrylic-sheets/or for a budget ass option (for the poor person that bought that amp), its possible to retrofit with this stuffhttps://lessemf.com/product/radiofilm/

author: coppice
author_rank: Super Contributor
timestamp: December 25, 2024, 05:25:58 pm
content: That transparent version of the case is amazing. Did he think that people seeing the crude "first rough prototype" style internals would be an enhancing factor?

author: tooki
author_rank: Super Contributor
timestamp: December 25, 2024, 05:44:09 pm
content: Quote from: EEVblog on December 19, 2024, 02:19:31 amI think you’re being awfully generous in assuming he possesses that much self-awareness (or social intelligence)… I think his actions so far suggest he does not, and thus won’t realize it even later.

author: andy3055
author_rank: Super Contributor
timestamp: December 25, 2024, 07:03:06 pm
content: A sucker is born every minute! These are good for people who buy directional audio cables

author: themadhippy
author_rank: Super Contributor
timestamp: December 25, 2024, 07:20:05 pm
content: QuoteBack in 2001'ish a certain Mr andrews claimed in one of his sales blurbs that measuring cable directivty was possible ,being curious i asked for more details on how they did it,and did get a replyQuoteHowever kimber never did get back to me

author: Bud
author_rank: Super Contributor
timestamp: December 25, 2024, 08:49:11 pm
content: Do not forget to burn-in your directional audio cable before use !

author: EEVblog
author_rank: Unknown
timestamp: December 25, 2024, 09:45:44 pm
content: Quote from: tooki on December 25, 2024, 05:44:09 pmWe'll know if he copyright strikes another video. Nothing so far...

author: andy3055
author_rank: Super Contributor
timestamp: December 26, 2024, 02:23:09 am
content: If all the manufacturers of various equipment, let alone audio gear, start claiming like he did, even Consumer Reports will have to close down. YouTube should have never taken it down in the first place and challenged him. It is not so hard to figure out that this is a disgruntled man.

author: 5U4GB
author_rank: Super Contributor
timestamp: December 26, 2024, 04:11:30 am
content: Quote from: Bud on December 25, 2024, 08:49:11 pmAnd dip it in liquid nitrogen to align the chakras.

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: December 26, 2024, 07:28:44 am
content: Quote from: andy3055 on December 25, 2024, 07:03:06 pmPsycological problems are not that fun, chasing details like theses ones is just a perceptible symptom of paranoia, most normal people see it when it happens to them and fight against it unless it become unperceptible for them and all others... and some fall into "the rabbit hole" and grow their illness.

author: EEVblog
author_rank: Unknown
timestamp: December 26, 2024, 07:54:13 am
content: Quote from: andy3055 on December 26, 2024, 02:23:09 amThey have to react that way, that's how the system works. A human isn't going to look into the details of such a lengthy video.

author: SolderSucker
author_rank: Regular Contributor
timestamp: December 27, 2024, 02:29:23 pm
content: New video which also covers Mend It Mark's video takedown from copyright attorney Leonard French:

author: andy3055
author_rank: Super Contributor
timestamp: December 27, 2024, 06:13:23 pm
content: Yay!