Car audio... Lol

[ericfx1984]

So on a group I'm in somebody posted what they claimed was an 80000 watt car subwoofer system...

Naturally I pointed out the absurdity of this

First I started by taking 80,000 watts and dividing that by 13.8 volts which works out to nearly 5,800 amps

Then I explained that a single 4/0 gauge cable is good for maybe 250 amps I explained that you would probably need about 20 of those cables to supply 5,800 amps

Of course then we have the issue of being able to charge... Not only do you have to be able to supply that much power but you need to be able to charge it... So when these guys talk about 100 and 200 amp alternators Even with several of those... How?

Another gentleman piped in and said that my math would be correct except I was forgetting one very important thing... Most of the professional car audio guys operate at 16.8 volts

Okay so we're still talking about 4000 plus amps?

So really it doesn't change anything

Then the guy proceeded to explain that I obviously didn't understand how "subwoofer ohms worked"


He explained that by lowering the ohms of the subwoofer that the amplifier was able to deliver even more power without pulling any more amperage... Lol

At this point I realized I was dealing with somebody who was just plain stupid...

The weird part is there are a lot of guys who were supporting it claiming that they have built several systems 10000, 20000, 40000, even 100000 watts

I explained to them That it's pretty simple to know what the actual power of an amplifier is


Let's say that you say the amplifier is 10,000 Watts

10000 watts , divided by 13.8 volts = 725 amps

So then the question becomes what is the size of the fuse you're using? If it's less than 725 amps then it's very unlikely that you're truly making 10,000 Watts

If you're running less than three or maybe four, 4/0 gauge cables and it's also very unlikely

But getting back to the 80,000 W deal

Let's say that I'm in a house... Like most houses I probably have 200 amp service... There are some houses that have double 200 amp service... But generally speaking 200 amps that's pretty standard... And getting any more than that is going to be dependent on your neighborhood having the ability to supply that from your electric company

80000 watts, divided by 120 volts = 666 amps... Way over what's your typical house can even provide

But let's look at it at 240 volts...

80000 watts divided by 240 volt = 333 amps... Still well above what most houses can deliver

And even though these numbers are significantly higher than what a house can deliver, they are still magnitudes simpler to deliver then delivering it at a 12 volt nominal system...


These car audio guys are nuts.. they have no idea what they're talking about and they believe all the hype and they're probably paying good money for the hype too

 

[Daddy Tanuki]

I worked the car audio and custom car scene in the 90's and the old class A and Class AB amps would pull somewhere around 200 amps in a 1200 watt system. this was actual average weighted across the frequency range from 20 htz to 20,000 htz. even with the newer digital (Class D and class T) amps you would need a lot of amps to make 10,000 watts.

most of these idiots are buying hot garbage amps with inflated numbers. its easy to do, just measure the output at 1kHz its the easiest frequency to drive. in that scenario a 100 watt amp could conceivably drive a tweeter in the 500 watt range without burning the amp up, but when driving subwoofers (cleanly and without distortion) the exact opposite is the case. 1000 watt amp is lucky to drive an honest 100 watts in the 20-120 htz range.

these jokers have amps that i used to call when lightening strikes. yeah it puts out 1,000 watts when lightening strikes the car... mind you most of them are not that smart to begin with.

 

[42OhmsPA]

Sometimes I miss my car audio / high school days... Just a small system, Volfenhag amp and a Kicker solo-baric L7 squeezed against the jump seat of my Nissan hard body. It sure was fun putting the sub through the sliding window to set it in the bed and putting change onto it....
Don't know how my hearing is still so good between the bass and explosives in my younger days.

Thanks for the trip down memory lane.

 

[Daddy Tanuki]

Sometimes I miss my car audio / high school days... Just a small system, Volfenhag amp and a Kicker solo-baric L7 squeezed against the jump seat of my Nissan hard body. It sure was fun putting the sub through the sliding window to set it in the bed and putting change onto it....
Don't know how my hearing is still so good between the bass and explosives in my younger days.

Thanks for the trip down memory lane.

yeah i specialized in SQ Plus and I still have tinnitus

 

[ericfx1984]

yeah i specialized in SQ Plus and I still have tinnitus

Huh? What? Did somebody say something?

 

[Sennen]

In 15 years of quality setups (no flea market off-brand crap) largest legitimate build I did was 5000 watts. Car had 3 batteries and would quickly drain them doing demos as 2 alternators couldn't keep up. Highest legitimate build I've seen personally is 10kw in an SUV. That beast had 4 alternators and 5 or 6 each of 4/0 wire running to the amp rack, which had 6 dedicated batteries. Things get nuts, but you hit a hard limit fast with 12v (16v) builds.

 

[ericfx1984]

In 15 years of quality setups (no flea market off-brand crap) largest legitimate build I did was 5000 watts. Car had 3 batteries and would quickly drain them doing demos as 2 alternators couldn't keep up. Highest legitimate build I've seen personally is 10kw in an SUV. That beast had 4 alternators and 5 or 6 each of 4/0 wire running to the amp rack, which had 6 dedicated batteries. Things get nuts, but you hit a hard limit fast with 12v (16v) builds.

See that seems realistic... Like that actually makes sense. In fact I would argue that with that much 4/0 wire That system is better wired than most people's off-grid solar setups

 

[Sennen]

Hence my build

 

[ericfx1984]

Honestly now I'm just trolling those guys... I keep asking them if they're really making 20, 30, 40 or even 80,000 Watts... What amplifier are they using? What kind of fuses are they using? What wire are they running? How are they charging the system?

 

[D71]

Honestly now I'm just trolling those guys... I keep asking them if they're really making 20, 30, 40 or even 80,000 Watts... What amplifier are they using? What kind of fuses are they using? What wire are they running? How are they charging the system?

It is the way of the World. No consequences of being punished for false advertising. Years ago a bunch of us complained about home - garage style air compressors being rated 5 hp on a 120v and 15-20 amp breaker … lawyers picked it up and sued them in a huge civil suit. Sears Craftsman to name 1 was caught up in it for their 5hp 120 volt air compressor advertising…as well as others. The advertising stopped for long time but you can still find it creeping back yet again. The air compressor deal made a lot of EE blush…they had been fooled… never looked at it. Once they thought about it were upset too.

I think a lot of things are over rated. It makes the unethical sales. Solar generator - Inverters are in my opinion over rated…. Ppl push the over rated inverters to max and usually get failures. If stay below max get better results. Car makers lie about mileage ratings all the time then throw out some special conditional testing to try and cover their claims. It really is pathetic for all the liars being allowed. When they do crack down for govt agency they’ll pick a company they don’t like to make an example. The rest usually take it as a warning. The USA Govt use to bust Hyundai over claimed mpg but yet all car makers were doing it. Hyundai was not on their favorites list.

Again just related type examples. We live in a lie with bunch of scammers which often do it intentionally. Then the ignorant or retards jump on for the ride. The only make the problem much worse. Some ppl are meant to be fleeced…. sometimes look at them and smile. Like when FAUX Pearls came out remember a gf saying she loved that brand. I knew she was not the 1 - used a condom. It is funny world when you adjust the humor for it.

 

[Sennen]

not even posting the brand... first result on amazon search for '5000 watt amplifier'. 60 amp fuse

 

[ericfx1984]

So I kept challenging guys to show me a car audio system that could do 80,000 Watts and to show me what's in the system

So they give me a link to a guy claiming 80,000 Watts and he has
Four subwoofer amplifiers from a company called deaf bounce, apocalypse 20000. Well I look up the specs on the amplifier

They claim 20,000 Watts at 1 ohm at 18 volts

And then they suggest that you should use a single zero gauge power lead and a 300 amp fuse

So I do the math at 18 volts to produce 20,000 Watts with 100% efficiency would require 1, 111 amps

Then I calculate out 100 amps * 18 volts which works out to 5400 watts

And again that's still requires 100% efficiency

So in a lab maybe it can produce 5400 Watts but who knows at what frequency they are even measuring that

And of course they made the argument that declass amplifiers are more efficient... Yes but they can't be more than 100% efficient and they can't be 100% efficient at all... They're always has to be some loss

I do ham radio... And I have the highest license class you can get... But every now and again some guy will bring me a CB to work on he'll claim that the CB is doing 50 or even 100 watts... And while the meter might appear to do that it turns out that it's actually reading power up at a much higher frequency that has nothing to do with CB

Course the same thing happens with their amplifiers they will think that they're putting out a thousand watts or 2,000 watts... But then come to find out maybe about 3 to 400 Watts is actually real and usable

This almost makes me want to start doing car audio and then when giving system specs give actual system specs... How funny would that be when there's some guy that thinks he has 5000 W but gets beat by a guy who has a true thousand Watts

 

[ericfx1984]

So I kept challenging guys to show me a car audio system that could do 80,000 Watts and to show me what's in the system

So they give me a link to a guy claiming 80,000 Watts and he has
Four subwoofer amplifiers from a company called deaf bounce, apocalypse 20000. Well I look up the specs on the amplifier

They claim 20,000 Watts at 1 ohm at 18 volts

And then they suggest that you should use a single zero gauge power lead and a 300 amp fuse

So I do the math at 18 volts to produce 20,000 Watts with 100% efficiency would require 1, 111 amps

Then I calculate out 100 amps * 18 volts which works out to 5400 watts

And again that's still requires 100% efficiency

So in a lab maybe it can produce 5400 Watts but who knows at what frequency they are even measuring that

And of course they made the argument that declass amplifiers are more efficient... Yes but they can't be more than 100% efficient and they can't be 100% efficient at all... They're always has to be some loss

I do ham radio... And I have the highest license class you can get... But every now and again some guy will bring me a CB to work on he'll claim that the CB is doing 50 or even 100 watts... And while the meter might appear to do that it turns out that it's actually reading power up at a much higher frequency that has nothing to do with CB

Course the same thing happens with their amplifiers they will think that they're putting out a thousand watts or 2,000 watts... But then come to find out maybe about 3 to 400 Watts is actually real and usable

This almost makes me want to start doing car audio and then when giving system specs give actual system specs... How funny would that be when there's some guy that thinks he has 5000 W but gets beat by a guy who has a true thousand Watts

Well actually this one might be legit... I thought it was a single 0 gauge feed but it's actually six, 0 gauge feeds

 

[Sennen]

Deaf Bonce usually does their rated output, but this is a screengrab of their 4000 watt on a dyno.

 

[ericfx1984]

Deaf Bonce usually does their rated output, but this is a screengrab of their 4000 watt on a dyno.
View attachment 203311

Still how many guys are properly supplying it with power?

 

[Sennen]

Still how many guys are properly supplying it with power?

Given the relatively low cost of this amp (USD $800), I'm betting this amp has stranded a few folks with a dead battery. Anything beyond this power level (especially that 20kw one) I'm hoping is installed by a pro using lithium supplements on the amp rack.

 

[ericfx1984]

not even posting the brand... first result on amazon search for '5000 watt amplifier'. 60 amp fuse
View attachment 203214

Oh I love crap like this

 

[ericfx1984]

Oh my lord these guys are making my head hurt... Some guy just tried to "educate me"

He told me that I obviously didn't understand how electricity works, he claimed that amperage works in opposition to voltage and that low volt systems are able to produce large amounts of amperage as a result...

I think he's lost his mind

 

[Sennen]

Ohm's Law isn't a suggestion...

 

[ericfx1984]

Ohm's Law isn't a suggestion...

They treat it more like it's ohm's folly