Nice High End 2000W amplifier. - Page 1
Forum section: electronics / general

author: Unknown
author_rank: Unknown
timestamp: March 28, 2020, 10:12:25 pm
content: https://www.aliexpress.com/item/33062435069.htmlYeah... So this somehow strikes me as... Not exactly 2kw.. I see they have a 12V DV input jack on the back too...Weird Creature.

author: Ysjoelfir
author_rank: Frequent Contributor
timestamp: March 28, 2020, 10:38:32 pm
content: I just can't take anything with such a remote control serious.

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 28, 2020, 10:41:02 pm
content: The customer reviews show some internal photos. It’s surprising to see a toroidal power transformer although it can’t be much bigger than about 75-100 VA and that’s being generous. I guess in the usual Chinese rating system, it’s probably good for at least 500 VA on the label

author: grumpydoc
author_rank: Super Contributor
timestamp: March 28, 2020, 10:52:35 pm
content: The spec is actually 200W RMS per channel - that might be more honest than 1000W per channel but as WattsThat says even that looks wildly optimistic given the transformer.I suspect that, given its dimensions of 29x24x10cm the initial impression on unboxing will be "disappointingly small"

author: Circlotron
author_rank: Super Contributor
timestamp: March 28, 2020, 10:53:09 pm
content: Single side non plate through pcb = cheap junk. All through hole components - getting less common in this day and age. And some of those reviewers are easily pleased.

author: grumpydoc
author_rank: Super Contributor
timestamp: March 28, 2020, 11:33:00 pm
content: What amuses me is the description of "Professional Stereo Digital Echo Karaoke Mixer Power Amplifier" - because no "professional" is going to touch this with a barge pole.Quote from: Circlotron on March 28, 2020, 10:53:09 pmWell, to give it due appreciation it appears to be a double sided board, possibly evenwiththrough hole plating (kinda hard to tell from the photos, but definitely tracks component side).The output stage looks like maybe 20W though.But at a massive price of USD 36 or so, it definitely qualifies as cheap junk.- but, then, at that price it might even be value for money and if it will run off a 12V supply it might even be vaguely useful outdoors away from a mains supply.

author: Unknown
author_rank: Unknown
timestamp: March 28, 2020, 11:43:20 pm
content: Well, that 12v DC 5A input on the back... IF that's anything to go by 14.4v x 5A = 72w / 0.7 calculating with 70% efficiency = 50w total max output.

author: Gregg
author_rank: Super Contributor
timestamp: March 29, 2020, 12:28:50 am
content: WOW, that pile of wank has enough knobs and slide pots to get the distortion just the way an audiophool wannabe likes it

author: rsjsouza
author_rank: Super Contributor
timestamp: March 29, 2020, 12:37:36 am
content: Well, one can always gut it and put a decent amplifier inside...

author: M4trix
author_rank: Frequent Contributor
timestamp: March 29, 2020, 01:00:56 am
content: All I can say is... My Goodness !

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 29, 2020, 01:05:44 am
content: Quote from: rsjsouza on March 29, 2020, 12:37:36 am+1I was thinking it might be re-purposed as a power supply enclosure, complete with rear mounted output and sense terminals

author: rsjsouza
author_rank: Super Contributor
timestamp: March 29, 2020, 01:16:16 am
content: For a candidate to be gutted and placed in a living room, the one below is a bit nicer looking - if you are intogold.#Aliexpress US $55.06 48%OFF | 920W 220V 5CH bluetooth HiFi Stereo AV Surround Amplifier FM Karaoke Cinema Home Home Theater Amplifiershttps://a.aliexpress.com/_dUcE1Ue

author: M4trix
author_rank: Frequent Contributor
timestamp: March 29, 2020, 01:20:38 am
content: The worst part is that a bunch of buyers already fell on this scam. They even left a high positive feedback !

author: Haenk
author_rank: Super Contributor
timestamp: March 29, 2020, 01:24:58 pm
content: Quote from: grumpydoc on March 28, 2020, 11:33:00 pmI would consider it "fair value for the money", not junk - lots of features but (of course) far from being "good HiFi equipment". The 12V supply might make this a good choice in certain cases.

author: grumpydoc
author_rank: Super Contributor
timestamp: March 29, 2020, 06:10:49 pm
content: Quote from: M4trix on March 29, 2020, 01:20:38 amCertainlyif genuineThey could just all be shils though.Quote from: Haenk on March 29, 2020, 01:24:58 pmIt is probably worth keeping sight of the fact that it is less than 40 bucks so if it basically works (apart from the laughable spec on the power output) I would say fair enough.But it could quite easily be junk even taking the purchase price into account.

author: Unknown
author_rank: Unknown
timestamp: March 29, 2020, 06:19:02 pm
content: Quote from: grumpydoc on March 29, 2020, 06:10:49 pmNot likely, false feedback is much more likely to contain some bad reviews.

author: madires
author_rank: Super Contributor
timestamp: March 29, 2020, 06:21:35 pm
content: They mean 2000 Chinese Watts PMPO.Like the cheap PC speakers in the old days.

author: Unknown
author_rank: Unknown
timestamp: March 29, 2020, 06:22:42 pm
content: Quote from: madires on March 29, 2020, 06:21:35 pmaYeah... "Possible Maxmum Power Output" Measured/calculated at 100 times the voltage and for a brief moment before failure.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 30, 2020, 12:29:21 am
content: Quote from: SantaClaw on March 29, 2020, 06:22:42 pmPC speakers? This exists since the stereos and boomboxes of the 80's - perhaps even earlier.Funny how in portuguese the PMPO acronym translates perfectly as "Potência Máxima Para Otários" ("Maximum Power For Suckers"). Is there a similar translation for English?

author: blacksheeplogic
author_rank: Frequent Contributor
timestamp: March 30, 2020, 09:27:25 pm
content: Quote from: M4trix on March 29, 2020, 01:20:38 amIt's got lots of switches & dials & sliders & buttons & lights & usb & it's painted black! Even looks rackable!!! - nobody cares if it works, it's all about taking selfies with it in the background.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 31, 2020, 12:22:58 am
content: This thing is like 50 bucks or so (you can probably have it for less). What would anyone expect from this apart from the enclosure really?You can't accuse them of trying to rip off people. They're selling cheap shit for cheap and you get some reusable pieces from this.Whatever is inside, it's probably worth the price as spare parts.

author: Circlotron
author_rank: Super Contributor
timestamp: March 31, 2020, 01:12:13 am
content: Quote from: SiliconWizard on March 31, 2020, 12:22:58 amI wonder if it's actually built from new parts?

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 31, 2020, 01:22:33 am
content: Quote from: Circlotron on March 31, 2020, 01:12:13 amIf they were using recycled parts, I think that would be actually a good thing. Less waste for the planet.

author: Circlotron
author_rank: Super Contributor
timestamp: March 31, 2020, 01:41:14 am
content: Quote from: SiliconWizard on March 31, 2020, 01:22:33 amThat's quite true. Just that it would add to the spirit of misrepresentation. In for a penny, in for a pound.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 31, 2020, 04:42:09 pm
content: Quote from: Circlotron on March 31, 2020, 01:41:14 amWell, they make stupid claims indeed, but not this one. I don't think they ever claim all parts in this are brand new.Anyway, there are just so many of those fake products (I would call them fake) on Aliexpress and the like, you could spend a lifetime just listing them.Selling low-cost products that "look" like the real deal, but only look like it (and not from up close) is extremely common on those platforms, for all kinds of products really.One popular kind of items are the tablets - sold at under $150, with claimed specs of an equivalent $600 product or over. When you dig a little deeper, you find out that materials are utter crap, and the CPU and RAM are absolutely NOT what is claimed. They go as far as tweaking the firmware to make common hardware description apps report their false claims. It's a whole business model in itself. I wouldn't put that in the "dodgy technology" category. The technology itself is not dodgy, this is just scamming.

author: Cyberdragon
author_rank: Super Contributor
timestamp: March 31, 2020, 07:01:59 pm
content: It is dodgey, some of the review are claiming they had to recap it and do mods just to get it to work "right" out of the box.Of course then they were like "5 stars, after I repaired it it works great!"

author: grumpydoc
author_rank: Super Contributor
timestamp: April 01, 2020, 11:16:21 am
content: Quote from: Cyberdragon on March 31, 2020, 07:01:59 pmApparently youcanfool some of the people all of the time.

author: temperance
author_rank: Super Contributor
timestamp: April 06, 2020, 10:24:03 pm
content: An amplifier doesn't need a transformer sized for it's continuous output power. A 60VA transformer can easily power a 100W amplifier without ever overheating even when one likes to play heavy compressed music. The same can be said about heat sinks. The transformer in class D amp can be made even smaller without any trouble.

author: madires
author_rank: Super Contributor
timestamp: April 07, 2020, 10:39:45 am
content: Try to measure that with a 1kHz sine wave and load resistors.

author: temperance
author_rank: Super Contributor
timestamp: April 07, 2020, 02:27:05 pm
content: That won't work of course. But you can try listening to a sine wave at full power for while if your loudspeakers can handle that. But in that case, you're ears wont be able to handle such things.Peak to overage ratio's for various releases can be found here:http://dr.loudness-war.info/

author: schmitt trigger
author_rank: Super Contributor
timestamp: April 07, 2020, 02:36:24 pm
content: If you are able to find some fissionable isotopes inside, it may actually generate 2kw.Anyways, The box and controls look nice.As others have mentioned, for that amount of money, the best course of action is to scrap the guts and put a decent preamp/equalizer/mixer of your own design.

author: Cyberdragon
author_rank: Super Contributor
timestamp: April 07, 2020, 03:22:41 pm
content: Quote from: temperance on April 07, 2020, 02:27:05 pmIt won't work because trying to drive it anywhere near "full power" will cause the Chinese Smog (tm) to be emitted.

author: MrMobodies
author_rank: Super Contributor
timestamp: April 09, 2020, 04:34:05 am
content: Quote from: Ysjoelfir on March 28, 2020, 10:38:32 pmI recognize those sorts of remotes from somewhere or similar, I remember that type sold with cheap LED lightening controllers like this one:https://www.banggood.com/Mini-21-Keys-IR-Remote-Control-for-LED-Lighting-Strip-Light-p-1122069.htmlQuoteA universal one:https://www.yoycart.com/Product/541791619881/Quote

author: agtrbt
author_rank: Contributor
timestamp: April 10, 2020, 05:19:20 am
content: The remote control is a generic model.This item looks to have usable quality for non critical venues like auction rooms, tutorial classrooms and street protests. Overrated specs but will usually last for a few years.Risk of electrocution can be mitigated by feeding it with a good 12v power supply via the 12V input poles behind

author: Haenk
author_rank: Super Contributor
timestamp: April 10, 2020, 05:59:23 am
content: Btw. those are available as RF controls as well - which is obviously way more useful (got one together with a 5 EUR LED strip). FCC and CE - most likely "no".

author: rrinker
author_rank: Super Contributor
timestamp: April 10, 2020, 07:46:11 pm
content: I have 2 - one came with an RGB LED strip I got, and the other came in one of the Arduino parts and sensor packs I got. Seriously cheap.

author: Unknown
author_rank: Unknown
timestamp: April 11, 2020, 02:29:18 am
content: I have a ton of those remotes, they come with all kinds of Arduino kits, Cheap electronics, and god forbid, the first generation of Chinese made car head units. The cheap LCD displays that where popular for cars back in the early 2000's...