Its big! Car audio amplifier... - Page 1
Forum section: electronics / general

author: Monkeh
author_rank: Super Contributor
timestamp: October 27, 2013, 07:42:08 pm
content: Because it's important the people on the other side of the six lane motorway can hear your taste in music as they go past.

author: SeanB
author_rank: Super Contributor
timestamp: October 27, 2013, 07:44:22 pm
content: So that is where that month's production of Lelon capacitors went..... I was wondering who bought the batch.Should only take about a week to change them all when they die.

author: c4757p
author_rank: Super Contributor
timestamp: October 27, 2013, 07:47:55 pm
content: Quote from: Monkeh on October 27, 2013, 07:42:08 pmThe worst part is that once you've gone deaf, you don't even need to maintain a good taste in music. You might as well play an endless loop of a guy farting in your boom wagon, the bystanders are the only ones who have to hear it...I'm not sure if I am joking or not.

author: SeanB
author_rank: Super Contributor
timestamp: October 27, 2013, 07:54:25 pm
content: I did once hear a bus coming from 1km away along a busy road. I decided to wait for the next one that was not sound propelled. Back 2 rows of seats were missing, the area being one massive wall of subwoofers. I think the sound system definitely cost more than the 50 year old Leyland bus did.

author: tom66
author_rank: Super Contributor
timestamp: October 27, 2013, 08:25:45 pm
content: Those caps are 220V, 1000uF. I wonder how many times over it would kill you if you touched that bus while live.

author: Monkeh
author_rank: Super Contributor
timestamp: October 27, 2013, 08:27:06 pm
content: Quote from: tom66 on October 27, 2013, 08:25:45 pmAnd just how much you'd deserve it.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 27, 2013, 08:29:22 pm
content: +-175 volt rails

author: tized
author_rank: Contributor
timestamp: October 27, 2013, 08:36:28 pm
content: How fast would it drain the car batteries if you forget to have the engine running?More than just acoustic pollution to this beast...

author: tszaboo
author_rank: Super Contributor
timestamp: October 27, 2013, 08:42:14 pm
content: Wow, thanks for sharing. Can we bridge them?

author: Clint
author_rank: Regular Contributor
timestamp: October 27, 2013, 08:49:15 pm
content: Quote from: Monkeh on October 27, 2013, 08:27:06 pmTongue ?

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 28, 2013, 12:54:16 am
content: Quote from: AmmoJammo on October 27, 2013, 08:29:22 pmI guess it started out as a power inverter design? If you could score one of those for cheap (perhaps one with a bad DC/DC), it should be very easy to make it into a VFD for a small air conditioner.

author: c4757p
author_rank: Super Contributor
timestamp: October 28, 2013, 01:15:15 am
content: Quote from: AmmoJammo on October 27, 2013, 08:29:22 pmSweet mother of god, why!?How many watts does this thing put out? A quick back-of-the-envelope (OK, top-of-the-calculator) calculation gave somewhere between "on fire W" and "molten kW" per speaker...

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 02:04:47 am
content: Designed and built by Zenon in Korea. Should do just under 10,000 watts per amp into 1ohm. The first pic was too amps side by side

author: TMM
author_rank: Frequent Contributor
timestamp: October 28, 2013, 02:22:54 am
content: That's not an audio amplifier, it's a precision arc welder

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 02:59:26 am
content: And yes you can strap two together for 20kw into 2 ohm

author: PedroDaGr8
author_rank: Super Contributor
timestamp: October 28, 2013, 04:09:16 am
content: Speaking of arc welder. I remember a guy telling me back in the 90s a few of the amplifier companies used to do just that. To show their amps were stable into fractional ohms (at over 1kW) they would actually use them as arc welders.

author: rexxar
author_rank: Frequent Contributor
timestamp: October 28, 2013, 04:25:42 am
content: Quote from: PedroDaGr8 on October 28, 2013, 04:09:16 amThat's insane.

author: poorchava
author_rank: Super Contributor
timestamp: October 28, 2013, 07:57:32 am
content: I remember a guy on Polish electronic forums, who built a 3kW RMS (IIRC) AB-class audio amplifier. He was boiling water in a 50l bucket as a load test

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 28, 2013, 08:05:43 am
content: Quote from: c4757p on October 28, 2013, 01:15:15 amgod doesnt have a mother. where did you hear that bollock?

author: tom66
author_rank: Super Contributor
timestamp: October 28, 2013, 08:14:44 am
content: Is that 10kW continuous? I don't believe you can do 10kW with just a small cooling fan -- you'd need water cooling to do that."sweet mother of god" is a saying which refers to the Virgin Mary... it's a saying... don't take it too seriously.

author: Psi
author_rank: Super Contributor
timestamp: October 28, 2013, 08:24:02 am
content: Quote from: tized on October 27, 2013, 08:36:28 pmMath says 2-3min, but probably more like 30 sec due to the battery starting to melt/boil10kw is 833A

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 08:32:44 am
content: Battery life would depend entirely on how many batteries you have?These amps weigh in at 28kgs, and are of course class D, so I believe they have enough heatsinking to run fairly continuously

author: peter.mitchell
author_rank: Super Contributor
timestamp: October 28, 2013, 08:34:05 am
content: I am not certain but I thought on the highr power units they required a 24/36v/48v supply opposed to just 12v?Class D huh? Looking at the filtering they look like they'd be better as an AM transmitter at 10kw then. ..

author: grumpydoc
author_rank: Super Contributor
timestamp: October 28, 2013, 08:36:31 am
content: QuoteA few others have asked the same question - where the fuck do you get 20kW from in a car with 12V wiring and perhaps a 1kW alternator?Unless, of course, you plan on towing one ofthesebehind youEdit:QuoteOK, even at 48V that's over 400A without taking the amp efficiency into account.But, see above, where do you find 20kW in a car?

author: TMM
author_rank: Frequent Contributor
timestamp: October 28, 2013, 08:44:41 am
content: Lots of batteries. It's not uncommon for guys that run serious amps like this to have multiple (5+) 100Ah+ 12v batteries in parallel installed close to the amplifier. Cars that 'demo' their systems for extended periods often also have multiple 300A+ capable alternators as well.The standard battery/alternator in most cars is only good for about 1500W in short bursts and about 500W continuous.

author: wraper
author_rank: Unknown
timestamp: October 28, 2013, 08:45:59 am
content: Some years ago I watched some show on Discovery. They changed alternator and entire wiring in a car just to drive that amplifier. Wires were like 2 cm in diameter, maybe even more.

author: TMM
author_rank: Frequent Contributor
timestamp: October 28, 2013, 09:22:04 am
content: ^pffft fake.8000W:22500W:

author: wraper
author_rank: Unknown
timestamp: October 28, 2013, 09:23:51 am
content: Quote from: TMM on October 28, 2013, 09:22:04 amOf course it is. But you get the idea

author: tized
author_rank: Contributor
timestamp: October 28, 2013, 09:24:24 am
content: Quote from: grumpydoc on October 28, 2013, 08:36:31 amI have a 60kW (peak) electrical system in my car, it is used tomove the car(a hybrid), not the speakers.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 09:33:44 am
content: To run these two amps, I'd probably want six 130ah, 1000cca batteries as a minimumCar already has a 300+ amp alternator, but a second would help too!

author: tom66
author_rank: Super Contributor
timestamp: October 28, 2013, 10:19:29 am
content: There is no way that 10,000W DC-DC converter can do that with just that poxy fan - I mean if you even want to approach above 5kW output power (of a DC-DC) you start needing water cooling, just for the inductors!

author: nanofrog
author_rank: Super Contributor
timestamp: October 28, 2013, 10:21:44 am
content: Quote from: Pippy on October 28, 2013, 09:52:12 amTinnitus sucks.Didn't get it from loud noise/music, but that doesn't mean much (born with it).

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 10:23:05 am
content: Quote from: tom66 on October 28, 2013, 10:19:29 amGood thing there are no inductors on the power supply section then!

author: tom66
author_rank: Super Contributor
timestamp: October 28, 2013, 10:30:47 am
content: Quote from: AmmoJammo on October 28, 2013, 10:23:05 amHow on earth do you get +/-175V from 12V then? There are clearly six inductors on the input near the power input, which will form part of the DC-DC converter. It looks like a nonisolated topology, so at least the efficiency will be a little higher, but there's no way in hell each of those inductors is going to do ~150A continuously (plus peak currenbt, losses) without overheating the core and cracking it. Or causing magnetic saturation, which will be extremely destructive to the power electronics. Completely inadequate air flow, too. If you do demand 10kW from it, it will fail quickly.Not to mention, capacitor ripple current. Those look like Samyoung caps on the 12V side; nothing special, unlikely to have a high ripple current rating.

author: hedgewallace
author_rank: Contributor
timestamp: October 28, 2013, 10:34:31 am
content: Wow! They are some decent capacitors!I have seen big capacitors in microwaves (probably a little bit bigger than these), but there are so many of them!

author: c4757p
author_rank: Super Contributor
timestamp: October 28, 2013, 10:35:31 am
content: Yeah, I donotsee that thing putting out 10kW, and if it seriously can, I'd like to see how they did it, because I seriously have something to learn about power electronics...Quote from: Mechatrommer on October 28, 2013, 08:05:43 amWell yeah, if he doesn't exist he can't have a mother....(Let's not get started again) (Born and raised Catholic, still have thehabits)

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 10:40:06 am
content: They aren't inductors, they're transformers, and each will easily handle the ~2kw they need to. Im guessing you haven't done much with high powered car amplifiers before

author: tom66
author_rank: Super Contributor
timestamp: October 28, 2013, 10:45:41 am
content: Quote from: AmmoJammo on October 28, 2013, 10:40:06 amOh dear, clearly you do not know about power electronics(admittedly it is new to me too.) I'm not a car audio enthusiast, but that is irrelevant.Transformers at high frequency are even more lossy than an inductor. Because you have that crappy, lossy magnetic core in the middle. There is no fking way that one of those poxy torodial coils is going to operate at 2kW for any length of time without serious cooling. And one cheap 12V computer fan does not count as sufficient cooling!With the amount of power behind one of these amps I seriously would not want to be in the same room when (not if) it fails.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 10:47:30 am
content: You don't even know how big the cores are though... Lol

author: tom66
author_rank: Super Contributor
timestamp: October 28, 2013, 10:48:11 am
content: Quote from: AmmoJammo on October 28, 2013, 10:47:30 amI can estimate easily based on the surrounding size of other components, I'd say around 2~2.5 inches diameter and about an inch deep.Looking closely at the topology, it appears to be flyback/push-pull type. One of the easiest to design, since you can basically put any components in and get an output (of course don't expect it to be efficient or reliable!)

author: tom66
author_rank: Super Contributor
timestamp: October 28, 2013, 10:52:26 am
content: For reference, the transformer in the top center of this power board is capable of operating around 280W continuously. A transformer capable of 2kW would need to be much larger, especially if it accepts a very low input voltage of 12V.

author: Psi
author_rank: Super Contributor
timestamp: October 28, 2013, 10:56:14 am
content: Quote from: tom66 on October 28, 2013, 10:45:41 amIf you look closely you can see the windings are made up of a very large number of smaller enameled wires to reduce the loss from skin effect. Coupled that with a really good core material and the right switching frequency and a kW rating might work.Quote from: tom66 on October 28, 2013, 10:52:26 amThat's a transformer from consumer electronics (made to be ultra cheap) and it's not even a toroid. Totally different thing.

author: grumpydoc
author_rank: Super Contributor
timestamp: October 28, 2013, 11:04:39 am
content: Quote from: tizedOK, yes hybrids and EV's do have that sort of electrical power kicking around but not, as you say, to drove the in-car hi-fi.Quote from: TMMHmmm, I can see that would supply the current, at least short term - I guess you'd easily get 2kA out of 5x100Ah batteries.Mind you if a 20kWcapableamp were not grotesque enough the sound system is starting to look like it will render any vehicle impractical for normal use. I mean, speakers to handle 20kW are not going to be either small or light and you've just added 150-200kg of batteries into the equation.Quote from: TMMYou'd need to, to recharge that battery bank.Quote from: TMMPretty much what I said, I think.

author: amyk
author_rank: Super Contributor
timestamp: October 28, 2013, 12:36:50 pm
content: Quote from: AmmoJammo on October 28, 2013, 02:04:47 am100V@100A?QuoteI thinkthat's sort of the point of this...

author: grumpydoc
author_rank: Super Contributor
timestamp: October 28, 2013, 12:43:03 pm
content: QuoteAh, OK, hadn't heard of thatI suppose it's not surprising - given that humans are competitive by nature - that we should have contests to see who has the loudest sound system in their car.It does explain the need to supply the load for only a fairly short term.

author: ElectroIrradiator
author_rank: Frequent Contributor
timestamp: October 28, 2013, 12:43:45 pm
content: So this is where Disaster Area have their roots...Edit for great reference:Quote

author: GK
author_rank: Super Contributor
timestamp: October 28, 2013, 01:21:24 pm
content: Reminds me of this for some reason

author: TMM
author_rank: Frequent Contributor
timestamp: October 28, 2013, 01:52:10 pm
content: Quote from: Pippy on October 28, 2013, 09:52:12 amNot all of us drive around jamming at full noise on a daily basis lol.My system (pretty weak, 138.5dB) probably sees full volume for a few minutes a year at competitions - the rest of the time everything is virtually idling in sound quality mode :p140dB bass isn't too damaging to hearing. It's probably about as damaging as sticking your head out the window of a moving car. 150dB will make your ears feel funny. 160dB is insta-damage.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 28, 2013, 02:07:30 pm
content: Why are the "pros" even thinking about 12V when at those power levels, high voltage more than makes sense?And while there's certainly not many "proper" applications for such a powerful amp in a car, there are still a few. Like a mobile PA system.

author: kfitch42
author_rank: Frequent Contributor
timestamp: October 28, 2013, 02:16:20 pm
content: Quote from: grumpydoc on October 28, 2013, 08:36:31 amPerhaps you skip the whole mechanical->electrical->mechanical conversion nonsense. The Mythbusters built a diesel powered subwoofer that got over 160 dB spl at 16Hz.

author: Shock
author_rank: Super Contributor
timestamp: October 28, 2013, 02:45:24 pm
content: Once the Sony LCD TV was brought into the room the capacitors curiously failed.

author: Anks
author_rank: Frequent Contributor
timestamp: October 28, 2013, 03:10:15 pm
content: I work with sound equipment and hire Pro audio PA out to events and we always get asked how many watts by the daft promoters but the educated sound technicians are more interested in SPL and dispersion. A Precision Devices 1850 can be powered by a 500watt amp in the correct cabinet and create almost twice the SPL of most high end car drivers being powered from 2000watts.As for the amplifier being shown I would have to guess that the total clean sine wave output is nowhere near its spec.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 28, 2013, 03:14:00 pm
content: Quote from: kfitch42 on October 28, 2013, 02:16:20 pmOr go straight for the pulsejet!

author: c4757p
author_rank: Super Contributor
timestamp: October 28, 2013, 03:18:14 pm
content: Quote from: Anks on October 28, 2013, 03:10:15 pmI was just more interested in the sheer amount of power that passes through this thing. Couldn't care less how loud it is... Once it's beyond "unhealthy" I lose interest.But I do like power electronics, and nothing says "power electronics nerdgasm" like a precision arc welder

author: Monkeh
author_rank: Super Contributor
timestamp: October 28, 2013, 03:20:49 pm
content: Quote from: TMM on October 28, 2013, 01:52:10 pm"Isn't too damaging"Any avoidable damage is too much damage.

author: G7PSK
author_rank: Super Contributor
timestamp: October 28, 2013, 03:56:05 pm
content: They do not need to work for long as they are for Loud car competitions they play a single frequency for a short period and measure the sound output often well over 150 dba. They have to replace the glass with plastic bolted in otherwise it's blown out. That bottom video is of a van with 30 KW.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 28, 2013, 06:53:20 pm
content: Quote from: Anks on October 28, 2013, 03:10:15 pmWhy not?The amplifier pictured below happily does about 3500watts cleanly, and its less than half the size of the first amps pictured (I say "half" its probably bigger than that... lol)Well, when it has a heatsink on it, and isn't blown up

author: ciccio
author_rank: Frequent Contributor
timestamp: October 28, 2013, 07:50:41 pm
content: Quote from: PedroDaGr8 on October 28, 2013, 04:09:16 amAbout 1980 I met a guy, the late Brian Gary Wachner, founder of the BGW company (that still exists).He built very powerful amplifiers, and one was called "the Arc Welder Special".I saw a demo at some exhibition where they demonstrated their efficient protection circuit by creating big sparks when shorting the output terminals.The year after my company demonstrated our new amplifiers driving an electric drill with a 50 Hz signal at the input... just to do something different.In those years I had a second job: in my home lab I did maintenance and repairs for many importers of pro-audio gear, and I must admit that I've seen only one BGW amplifier, and many more of better known manufacturers..

author: Kryoclasm
author_rank: Regular Contributor
timestamp: October 29, 2013, 02:48:51 am
content: The military should weaponize these Boombox cars... ie paint them camo, and use them for front line offensive operations. Making your enemies heads explode!

author: TMM
author_rank: Frequent Contributor
timestamp: October 29, 2013, 04:12:20 am
content: Quote from: Monkeh on October 28, 2013, 03:20:49 pmTruth. I don't go to music concerts because my ears feel far worse for wear after...

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 29, 2013, 05:02:53 am
content: Quote from: ciccio on October 28, 2013, 07:50:41 pmAnd those who have actually tried to run a mains voltage drill from a 30V or so supply (did that as a failed experiment to really slow it down for operating a pasta maker - ended up getting a proper geared motor assembly) would know how easy it is to actually make one of those things turn. They should have used something bigger like an air conditioner (which is a remarkably difficult load unless the inverter is specifically designed for it) or a vacuum cleaner.

author: smashedProton
author_rank: Frequent Contributor
timestamp: October 29, 2013, 06:25:10 am
content: Quote from: tom66 on October 28, 2013, 08:14:44 amActually there is the holy trinity So the ghost man, Jesus and the father are the same, sui everyone Is right.

author: kfitch42
author_rank: Frequent Contributor
timestamp: October 29, 2013, 01:46:03 pm
content: Quote from: Kryoclasm on October 29, 2013, 02:48:51 amThere is a little known corollary to 'rule 34', if you can think of it, the US military has a weapon of it:http://www.psywarrior.com/loudspeaker.htmlhttp://www.npr.org/templates/story/story.php?storyId=4857417http://physicscentral.com/explore/action/speech-jam.cfm

author: SeanB
author_rank: Super Contributor
timestamp: October 29, 2013, 06:32:43 pm
content: Quote from: NiHaoMike on October 29, 2013, 05:02:53 amThey do run quite well from a 115V 400Hz aircraft power supply, though they have a lot less power and tend to sing a lot. Running them off the DC bus was good for light work like taking out rivets when there was no air supply available to run air tools.

author: tesla500
author_rank: Regular Contributor
timestamp: October 29, 2013, 08:37:43 pm
content: I'm just waiting for someone to modify an electric car traction inverter to drive subwoofers as a class D amplifier. A Tesla Model S inverter could drive almost 400kW of speakers if you add some filtering on the output! Would be 3 phase though, some interesting acoustic design would be needed.

author: MacAttak
author_rank: Unknown
timestamp: October 29, 2013, 11:10:11 pm
content: Reminds me of my younger days in competition car audio. My favorite amps were Orion "red" HCCA amps (not sure how well they are made these days - I haven't been involved in competition audio since the mid 90's), we would wire a number of 15" or 18" sub drivers in parallel - not uncommon to put < 1 ohm loads on them. The hardest thing was supplying enough current quickly enough to avoid clipping. It was normal practice to install special alternators along with a bank of deep-cycle marine batteries for the power system, along with a bank of supercaps very near to the amplifier hardware.At least once in their life everyone should get to experience 150+ dB of raw bass while sitting in the cab of one of those SPL show cars. It is a unique sensation - there is nothing else like it in the world. (and don't be an idiot and ignore the deafness warnings - wear the proper ear protection)

author: SeanB
author_rank: Super Contributor
timestamp: October 30, 2013, 05:46:28 pm
content: I had that already. Atar 09K50 at full afterburner with you standing next to it. Full body massage..........

author: Alex
author_rank: Regular Contributor
timestamp: October 30, 2013, 07:22:04 pm
content: This looks like the Phoenix Gold "The One". 12kW, bridgeable. In the words of the presenter:They began with a typical class D topology...and then someone threw the lunacy switch.Why increase the battery voltage when you can throw ferrite and copper at the problem?Alex.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 31, 2013, 05:40:18 am
content: Quote from: Alex on October 30, 2013, 07:22:04 pmDoesn't reallyThe transformers in "the one" don't look to have heavy enough gauge/quantity windings on them.... One webpage I found said the following:"Maximum power at 1 ohm at 16 volts was a ridiculous 9419 watts! If you do the math, that means the amps output to the speaker load was over 90 amperes, and over 90 volts. "Not sure how you advertise a 9400watt at 16volt amplifier as being 12,000watts :p The amp I pictured should do more than that off 14.4volts

author: senso
author_rank: Frequent Contributor
timestamp: October 31, 2013, 06:00:37 am
content: Peak value measured during 10ms, 1ms, or 0.1ms, or some stupid non-real world value..

author: 84GKSIG
author_rank: Regular Contributor
timestamp: October 31, 2013, 07:51:05 am
content: i guess if you like listening to your music in full rage, a little extra reserve current to stop bottoming out in the low frequencies or clipping is fairly important, but that is just silly even to me

author: Alex
author_rank: Regular Contributor
timestamp: October 31, 2013, 10:21:40 am
content: Quote from: AmmoJammo on October 31, 2013, 05:40:18 amNah, "the one" is clearly superior. You will have to return it now and get a real man's amp, if you can afford it!

author: Setar2k11
author_rank: Contributor
timestamp: October 31, 2013, 01:57:52 pm
content: That amp is just a toy.... This ,http://www.pknc.com/3phase_eng.html, is an amp, 2 x 20Kw into 2.66ohms, all in a 1U rack mount case.

author: Jon86
author_rank: Frequent Contributor
timestamp: October 31, 2013, 05:00:54 pm
content: Quote from: Setar2k11 on October 31, 2013, 01:57:52 pmHoly crap, I want one!

author: Six_Shooter
author_rank: Regular Contributor
timestamp: November 18, 2013, 05:50:24 am
content: Quote from: NiHaoMike on October 28, 2013, 02:07:30 pmBecause rules in every car audio competition league/organization dictate no more than 16V systems in most cases, some restrict, or at least used to, down to 14.4V. If they didn't it would be a lot easier to get more power.Quote from: MacAttak on October 29, 2013, 11:10:11 pmYep, that was also back when I got into Car Audio, right around 1992. The HCCAs were the hot ticket. I wanted one of the 2100 HHCAs so badly, a "200 watt" amplifier that was around 24" long, 10" wide and 6" tall.I was also fond of the 2250SX I think it was, in the same heatsink, only black, and wasn't a "high current" amplifier.Then there was the MS series from Phoenix Gold, I still haven't found anything comparable, and I have some Phoenix Gold Xenon stuff in my crawl space. :/Quote from: senso on October 31, 2013, 06:00:37 amI refer to those as "ILS Ratings" - If Lightning Strikes.Phoenix Gold used to be known for putting REAL output ratings on their products, but they were bought out and have been caught up in the same ILS ratings that most other companies put on their products to sell them. The good manufacturers will still publish the real ratings, usually at low THD and sometimes with a full range or proper range for that component frequency range.Even though I am very much into efficiency, both in space and power used by anything, I still can't help to like the look of surf board amplifiers, must be that guy thing...

author: zapta
author_rank: Super Contributor
timestamp: November 18, 2013, 06:48:31 am
content: Quote from: Setar2k11 on October 31, 2013, 01:57:52 pmBut does it come with Monster cables?

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: September 11, 2014, 10:20:49 pm
content: Hopefully getting these amps installed soon! Finally!Working on the sub box at the moment to house these subs.

author: nanofrog
author_rank: Super Contributor
timestamp: September 11, 2014, 10:40:16 pm
content: Quote from: AmmoJammo on September 11, 2014, 10:20:49 pmDoing SPL competition? Or just want to be heard half a mile away?

author: RobertoLG
author_rank: Frequent Contributor
timestamp: September 11, 2014, 10:49:21 pm
content: would be fun playing some dark electro

author: SirNick
author_rank: Frequent Contributor
timestamp: September 12, 2014, 07:24:10 pm
content: I'm a big fan of this one:http://www.parts-express.com/tang-band-w6-1139si-6-1-2-subwoofer--264-832I've built two boxes for this:One is a tapped horn good down to 38Hz, with a home-built 50W amp. More than enough volume for a small office, and goes deeper than the room's geometry makes it practical to hear anyway.The other is a ported box tuned to ~30Hz, just to see what it could do. It runs out of Xmax fairly easily, but it's impressive how much output you can get from a 6.5" driver. Two of them would be "enough" for music at reasonable levels in a home. Not quite enough huevos rancheros for home theater though.

author: jlmoon
author_rank: Unknown
timestamp: September 12, 2014, 08:46:47 pm
content: I'm still looking for the miniature therm o-nuclear reactor that is going to provide the required energy/joules to drive the incredibly and physically large loads this so called 20KW amp system is driving. Ok, is it under the seat, back floor pan where the spare was.. or where? The currents, heating and all the other parameters would be out the roof on this one. <<< Still impossible, physics rules!>>>

author: jlmoon
author_rank: Unknown
timestamp: September 12, 2014, 08:51:38 pm
content: Quote from: Jon86 on October 31, 2013, 05:00:54 pmNow we're talking.. 3phase power.. oh yes!!! Look at the output current and voltage on that bad boy. Not for a young player!

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: September 12, 2014, 09:09:43 pm
content: Quote from: jlmoon on September 12, 2014, 08:46:47 pmBattery box is going under the car to house six 130ah, 1000cca deep cycle AGM batteries.(the cardboard box pictured above was just to see how much space I had available)Also plan to have a 7th battery the same under the bonnet, and possible an 8th in the back next to the box.So, 1040ah worth of batteries, plus the 300amp alternator.

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 12, 2014, 09:28:34 pm
content: Take a look at some LiFePO4 batteries. They're very popular with DIY EV builders and are much cheaper than they used to be.

author: Strada916
author_rank: Frequent Contributor
timestamp: September 12, 2014, 11:32:45 pm
content: What value on watt are wt

author: SirNick
author_rank: Frequent Contributor
timestamp: September 12, 2014, 11:36:01 pm
content: Uh, watt?

author: Towger
author_rank: Super Contributor
timestamp: September 13, 2014, 08:13:31 am
content: What you need is a tesla battery. Should give enough power for 3 or 4 hours.Btw I did not think cars still used spring leaf suspension!

author: nanofrog
author_rank: Super Contributor
timestamp: September 13, 2014, 11:46:01 am
content: Quote from: Towger on September 13, 2014, 08:13:31 amPerhaps it's a truck or SUV (still use leaf spring suspensions)?

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: September 13, 2014, 11:58:07 am
content: Its a 2005 Ford Falcon wagon.

author: VK5RC
author_rank: Unknown
timestamp: September 13, 2014, 12:11:40 pm
content: Dumb question, is the aim SPL or power consumption, if the former, aren't the speakers/enclosures always the weak link?

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: September 13, 2014, 01:02:08 pm
content: Aim is "musical" spl... its intended to play music, but get loud..Its not so much the speakers that let spl down, "anything" can get loud.

author: Yago
author_rank: Frequent Contributor
timestamp: September 13, 2014, 01:33:52 pm
content: Do I wear the Dave Jones or Desmond Morris hat?

author: tom66
author_rank: Super Contributor
timestamp: September 13, 2014, 03:34:00 pm
content: When we get EVs more commonly appearing on the streets I'm sure we'll see nutters tapping into the 400VDC battery pack... feel like 50kW into an audio system?

author: GK
author_rank: Super Contributor
timestamp: September 14, 2014, 01:15:32 am
content: I finally found cause to introduce myself to my new neighbor, by slamming on the fence and calling him a fucking moron at the limit of my lungs. Half the neighborhood must have heard it. Ten o'clock at night, "fullie sik bro" car sub woofer blaring something not even discernible as music, right opposite my kitchen window, which is rattling; can't even properly hear the TV in the living room, FFS. Has been nice a quiet since though.

author: Uup
author_rank: Regular Contributor
timestamp: September 16, 2014, 04:52:15 am
content: Quote from: AmmoJammo on October 27, 2013, 07:38:09 pm[ In a "Crocodile Dundee" voice ]That's not a capacitor...Thisis a capacitor!

author: bktemp
author_rank: Super Contributor
timestamp: September 16, 2014, 06:28:25 am
content: Quote from: Uup on September 16, 2014, 04:52:15 amThat's also not a capacitor...Thisis a capacitor!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 16, 2014, 09:29:36 am
content: Quote from: bktemp on September 16, 2014, 06:28:25 amOh, please.Tim

author: nitro2k01
author_rank: Frequent Contributor
timestamp: September 16, 2014, 10:17:36 am
content: Quote from: T3sl4co1l on September 16, 2014, 09:29:36 amWhile the capacitance is massive, I'm concerned about all arcing that happens all the time. On the plus side, the self-healing is excellent.

author: moemoe
author_rank: Regular Contributor
timestamp: September 16, 2014, 10:30:37 am
content: Some time ago I read this article:http://www.spiegel.de/auto/fahrkultur/db-drag-racing-autos-mit-getunten-soundanlagen-a-990410.html(sorry, it's german).But what I rememberd it is this statement:QuoteQuick translation:Quote

author: SeanB
author_rank: Super Contributor
timestamp: September 16, 2014, 06:52:09 pm
content: Quote from: Uup on September 16, 2014, 04:52:15 amI picked up bigger ones than that at the roadside as scrap. 4700uF 450V.Today a 1uF 200VAC/250VDC 0.1% standard capacitor in a box, bought at the scrapyard with another 24kg of other stuff for $9. There were a whole lot of decade boxes as well, but those had already met the not so gentle treatment.

author: Falcon69
author_rank: Super Contributor
timestamp: September 17, 2014, 01:08:03 am
content: I used to be involved in alot of this car stereo stuff.I'm 40 now, and sadly, I'm often finding myself saying, "sorry, what did you say?"Wish I could go back now and build a bigger one! Then that way, I wouldn't have to hear (or somewhat hear) what anyone has to say these days!

author: Falcon69
author_rank: Super Contributor
timestamp: September 17, 2014, 02:43:58 am
content: Seriously though.The SPL/DB competitions that are held all over the USA are just amazing. The amount of sound that comes out of some of these vehicles is just overwhelming.You can be 100ft away, and watch the hairs on your chest move from the sound.When the competition is held, the Deck (stereo) is usually placed out of the vehicle a certain amount of feet away, or is operated by a remote. To sit inside of these vehicles without hearing protection, can and will damage eardrums. You saw in one of those videos of that girl/guy's hair moving. imagine the sound pressure of 10 fold doing that to your ear drums. It's really amazing the air pressure or displacement some of these 12 or 15 inch woofers can do.Looking at some of these vehicles, they aren't even street legal anymore. They come in on trailers most of them. the Windows, especially the Windshield, are Thick Plexiglass and pop riveted or bolted on. Some of these vehicles run multiple Alternators and Batteries. Huge Capacitor Banks to deliver the quick power needed for when those multiple amplifiers draw power for when the bass notes hit. If you look in one of the videos another member linked, you can see the windshield vibrating and moving like an inch. You can also see that same windshield has duct tape all over it. LOLAlma Gates, rest her soul, what an old women who was seriously involved in alot of these competitions. I remember one competition I went to, where her vehicle hit over 185db. That was many years ago. I'm sure today, vehicles are louder then that.But, on the flip side, these competitions don't just offer SPL/DB competing vehicles. They offer vehicles competing against each other for sound quality, and some of these vehicles are just, well, just WOW! Listening to some of these vehicles, makes you wish you could go drop $30,000 on a system for your own vehicle, the sound is so clean.I had a vehicle that was pushing 6000 watts. I had to run a second battery, as well as a dedicated high efficient alternator to keep the system going. As a precaution, I used an RV relay that turned off connection to the vehicles main battery if the ignition was turned off, that way, If I had i had listened to the stereo to long with the ignition turned off, I could still start the vehicle when the battery had run dead.

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 17, 2014, 04:26:03 am
content: I wonder what they would be able to do once they start hacking hybrids and EVs...

author: tom66
author_rank: Super Contributor
timestamp: September 17, 2014, 08:37:45 am
content: Quote from: T3sl4co1l on September 16, 2014, 09:29:36 amThe capacitance of earth is only about 700uF.

author: Uup
author_rank: Regular Contributor
timestamp: September 17, 2014, 01:47:36 pm
content: Quote from: SeanB on September 16, 2014, 06:52:09 pmI know larger capacitors are available. When that particular equipment came in the other day, seeing those two enormous 3300uF 400V capacitors reminded me of the OP's monster car amplifier pictures. So I posted for fun. The picture doesn’t convey how ridiculously large those capacitors really are!The largest capacitors (physically) that I usually encounter in equipment passing the work bench are BHC (Now Kemet) 470uF 450V, but are difficult to source locally so have been using their 400V types. Working voltage is fine for the application.Today, a rather unusual Japanese made power supply came in...It has 6 10,000uF 100V capacitors for the AC to DC board.What? You picked up a 4700uF 450V capacitor?That's not a capacitor...Thisis a capacitor!Well, actually 193 10F capacitors on the three lower PCBs of the DC to DC boards!That’s 1,930,000,000uF if removed and individually totalled!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 17, 2014, 08:28:06 pm
content: Quote from: tom66 on September 17, 2014, 08:37:45 amYeah, but good luck finding any commercial part that'll do a billion volts.

author: Falcon69
author_rank: Super Contributor
timestamp: September 18, 2014, 10:03:16 pm
content: AmmoJammo,Looks good.if you don't already know this, (i learned when I was working for a company installing custom Stereos), if you mix sawdust in with resin, pretty thick, and smear it all over the box inside, it does one of two things....1. Seals up the inside of the box2. Creates a bumpy effect inside the box which will break up the sound waves inside the box so they don't reflect back into the subs.Doing this will actually make your sound quality, DB, and SPL better.

author: TheEnd
author_rank: Contributor
timestamp: September 18, 2014, 11:27:31 pm
content: 1F caps are pretty common to fit in an install, some of the bigger multi battery installs have 1 capacitor per battery, although there's a big argument over whether they work or not.Same old audiophile stuff, some people will say they can hear the difference, others will have supplys, multimeters and test gear and say they do nothing useful.Remember when you could get a single blade razor, and now it's doubles, quads, and 6 blades these days, car audio caps have gone the same way.If anyone can buy a 1F power cap, how do you stand out?http://www.lanzar.com/sku/VCAP10000/Vector-100-Farad-16-Volt--Hybrid-Double-Capacitor-100F cap, you wouldn't want to touch a spanner over the terminals on that...Anyway, flashing blue LEDs... just take my money!!!!

author: dannyf
author_rank: Super Contributor
timestamp: September 18, 2014, 11:31:58 pm
content: I feel bad for that car.

author: RobertoLG
author_rank: Frequent Contributor
timestamp: September 18, 2014, 11:52:38 pm
content: Looks really cool

author: SirNick
author_rank: Frequent Contributor
timestamp: September 19, 2014, 12:10:21 am
content: OK, so.... that's a ported enclosure then? What's the tuning frequency? How much volume per driver? Doesn't look like all that much, what with the enormous basket, although you're starting to run out of car as it is.Car audio people tend to get batteries and caps confused. A 1F cap will relieve some of the Vbatt droop for transients, but your dubstep bassline will just pull the cap down to the sustained battery voltage. Either way, if the amp is built worth a crap, it has sufficient PSU capacitance internally to handle XXms loads for the kick drum's bite, and adding another externally isn't really necessary.

author: SL4P
author_rank: Super Contributor
timestamp: September 19, 2014, 01:41:22 am
content: I always enjoy seeing those 2000W (peak) chinese music boxes on display, that dim the power supply LEDs even on quite gentle tracks.I reckon they'd be hard pressed putting out 10W rms.

author: TMM
author_rank: Frequent Contributor
timestamp: September 19, 2014, 06:19:49 am
content: Quote from: Falcon69 on September 18, 2014, 10:03:16 pmThat's funny because the SPL competitors i know swear by coating the inside of their boxes with resin to achieve a glass-smooth finish. They claim it is worth 0.1-0.2dB. I still think they are mad. A few millimeters deviation in surface finish isn't going to do anything substantial to bass frequencies which have wavelengths measured in meters.

author: Falcon69
author_rank: Super Contributor
timestamp: September 19, 2014, 08:40:14 am
content: NO! Not a smooth free finish. That's why you throw sawdust in the resin and mix it before pouring it.You want a bumpy and jagged effect. That's where the waveforms will get broken up and not reflect back into the speaker.A glass smooth finish is a No No

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: September 19, 2014, 09:56:34 am
content: Quote from: TMM on September 19, 2014, 06:19:49 amsmooth inside, rounded corners in the right places, and a flared/rounded exit on the port will always gain something, plus other things, like rounding the back edge of the woofer cutouts, removing the plastic covers from the subs magnets if they have one, and even duct taping parts of the box can all gain fractions of a decibelIn competition, you could win or lose by 0.1dB, and I've beaten people by 0.1 and 0.2dB before, so every 0.1dB counts!

author: dannyf
author_rank: Super Contributor
timestamp: September 19, 2014, 05:24:07 pm
content: QuoteWhether they do it is not important;Whether they are believed to do it is very important.

author: SirNick
author_rank: Frequent Contributor
timestamp: September 19, 2014, 06:44:00 pm
content: This stuff is actually regularly measured WRT to the front baffle of a speaker. E.g., should the tweeter be placed symmetrically or offset to one side? How close to the edge? Should the edge be rounded? What about rounding the edge of the cutout?It is mostly all fractions-of-a-dB stuff, but the usual purpose is to smooth out (or at least distribute the imperfections in) the frequency response due to reflection and refraction. Not so much affecting the absolute loudness. Even chamfering the backside of a driver's cutout is intended more to prevent non-linear response, and usually only in the case where the baffle is a significant portion of the driver's depth.For bass frequencies, the difference is mostly immeasurable -- somewhere in the noise. Rounding the port is helpful -- mostly to prevent turbulence at the mouth from being distinctly audible. (Hey, that could evengiveyou a couple tenths of a dB lead.)So yeah, all these things do contribute in minute ways, although I have my doubts that most aspiring Sonic Boomers have access to equipment with accuracy high enough to measure the differences in a repeatable fashion. Just as likely to skew the results from a butterfly farting half a meter away. Could be wrong though.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: September 19, 2014, 08:27:03 pm
content: Quote from: SirNick on September 19, 2014, 12:10:21 amsubs are inverted (for now anyway) box is 350 litres tuned to about 36Hz, although I believe its actually slightly lower, closer to 34hz :pI would have rathered closer to 400 litres, but wanted to keep it below the window line.

author: cimmo
author_rank: Frequent Contributor
timestamp: September 20, 2014, 07:32:50 am
content: What a waste of human endeavour.

author: Falcon69
author_rank: Super Contributor
timestamp: September 20, 2014, 07:49:26 am
content: Quote from: cimmo on September 20, 2014, 07:32:50 amNah, there's good satisfaction rolling by your x-girlfriend's at 3 in the morning on a Sunday night bumping your system..........then come back every half hour.

author: SeanB
author_rank: Super Contributor
timestamp: September 20, 2014, 10:08:30 am
content: 4AM the next door guy will be waiting for you with a baseball bat, a shotgun, a jerry can of petrol and a lighter.When the guys upstairs would not listen after 3 nights straight I went down and turned off the power. If I had been nasty _____________________________________________. Peace ensued, and they kept the volume down afterwards.

author: jlmoon
author_rank: Unknown
timestamp: September 23, 2014, 09:34:21 pm
content: Quote from: bktemp on September 16, 2014, 06:28:25 amno, that's a Door Stop!

author: diyaudio
author_rank: Frequent Contributor
timestamp: September 26, 2014, 08:55:22 pm
content: Quote from: AmmoJammo on October 27, 2013, 07:38:09 pmInteresting amplifier, car audio is no longer a popular sport like it used to back in the days, this is not a typical everyday amplifier. (im to old to find value in justifying putting a amplifier like this in an everyday vehicle.The power electronics section is the most interesting to me, those six toroidal cores are wired in series approximately 25 volts each capable of at least 30 amps easily through each winding, the small core looks like a LC filter to suppress large AC ripples on the 14.4 DC bus front end as a result of a massive currents involved during loud playback.The amplifier section is nothing innovative in terms of today's standards, its just a class-d amplifier probably a clocked modulator. majority this amplifier is made up of a DC TO DC converter with massive heat-sinking surface area.

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 26, 2014, 10:12:58 pm
content: The insides look just like a power inverter... Because that's what it is...A lot of cost can be cut out (and efficiency improved!) by using a common 120/240V generator run direct off the engine, then just rectifying that and driving an IGBT power stage direct off the HVDC bus.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: October 10, 2014, 09:00:34 pm
content: Here's another high powered amplifier I'm meant to be fixing... hmm...I'm trying to source a replacement transformer... but failing that, what would you do?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 10, 2014, 10:31:05 pm
content: Niiice...At least it was obvious enough...maybe.Easy enough to desolder (actually, desoldering that pile of wire called a transformer is probably the hardest thing..), take off the windings and find the burnt spot. Apply tape (preferably mylar or kapton) and put it back together.Tim