High efficiency sub amp in 1000w area

[headless 10+ year member]

That guy just has to be a troll. Either that or I just lost all semblance of respect I ever had for PG.

You don't 'take the magic' out of a process that is easily definable with known formulaic equations by making up your own, super ****ed up formulaic equations that only work under one specific condition, and only then by fluke. I pity the poor ****ers who you taught this shit to. You want 'a good place to start'? How about the real method you use to calculate amp draw given a particular efficiency and output rather than some shit you made up because you or someone else didn't understand it? Ohm's law doesn't need to be ****ing simplified. Christ.

 

[CarAudioGuru 10+ year member]

OK smart ***. How much current does it take to blow a 50 amp fast blow fuse. If you are soo.oo ****ing smart.

Pretty simply question.

And you have how many patents? And Design and Engineering awards? I have 2 patents and 5 design and engineering awards.

All I am doing is trying to take a very complex idea (for car audio guys) and making it simple. Get them to understand the idea that it takes current to make power and that is not magic.

Ohms law can be very confusing, and I try to teach very practical , everyday ways to go out and measure power and current. SIMPLY.

Listen I have dealers that thought a balanced line transmitter (with a receiver) were "wireless". OK! Ya know like 2.4G stuff.

And,.....You've tested how many amplifiers in car and on a bench?? HMMM?

So your credentials are????? You've designed and had taken to manufacture how many car audio products? I have designed and manufactured 1,000's of products.

Look I agree, every retailer should understand and USE Ohm's law. Hell I can't even get these guys to have an RTA in their stores. much less a O'scope and good meters.

I travel the USA all the time and it is very sad that knowledge is not used.

Again your are right...OHM's law is relatively simple, BUT you need to know REAL efficiencies of amplifiers thru empirical (real world, in car ) testing.

At PG we tested a ZX450 at 71% efficiency on the bench. BUT...when we put it in a car, connected to speakers the REAL efficiency was more like 50%.

The only way to know that is to do a LOT of testing, in car, with scopes, meters, Audio Precision Ones, etc.

And YOU'VE done that??? Cause I have, many times.

 

[95bat 10+ year member]

Ok CarAudioGuru, we get it, your e-peen is bigger than everybody elses.

Back on topic, amp suggestions...

 

[CarAudioGuru 10+ year member]

Basically any 1000 watt amplifier made in the last 3 years from a reputable manufacturer. Meaning:

MTX

Rockford

Kicker

Crossfire

AutoTek

HiFonics

ARC

Audison

Etc

Etc

Basically whatever rings yer bell. Price and availability are the real issues.

I would look for variable crossover capability as well as adjustable subsonic and bass boost frequencies.

Real handy when you build big *** boxes with huge vents (Odd-Order alignments/Chebyshev type filters) i.e, DB type enclosures.

As they tend to "un-load" at very low frequencies(the proverbial "Wholly Shit the woofers gonna launch syndrome")

Does a warranty mean anything to you? if not buy off Craigslist or Ebay.

 

[helotaxi 5,000+ posts]

Any installer that can't grasp and apply the very basics of Ohm's law NEEDS to go out of business. They are a hindrance rather than asset to the industry. I learned this stuff in high school.

And who'd have guessed that a Class A/B amp would prove less efficient when used on music rather than a full power test...oh that's right, anyone that knows jack about amplifier topology and knows that Class A/B amps get less efficient as they move away from full power...

I do agree though, in real world use the difference in current draw between Class D sub amps of the same real power is going to be negligible. If test tones, SPL competition and "music" with long, droning, loud bass are part of your plans, efficiency matters, but for normal people with music that uses real instruments, it really isn't going to matter.

 

[CarAudioGuru 10+ year member]

Helotaxi- I TOTALLY agree that anyone in the car audio industry that does not grasp fundamental things, like Ohms law should be out of business.

It amazes me on a daily basis how many incredibly stupid retailers there are, who are still in business.

Scary actually.

By the way, Ohms law for current draw is I=P/E correct? But that is assuming 100% efficiency.

So my funky formula that has you take Total power X 2 (assuming worst case Class a/B and 50% efficiency)and divide by Dc volts is so far off?????

Huh?????

 

[helotaxi 5,000+ posts]

Works OK for A/B amps except that you're really making assumptions that aren't accurate. You method assumes 50% efficiency at full power which is really bad. If we're looking for worst case, then OK, but if we're talking real world, apply reality all the way 'round. Figure in crest factor which will greatly reduce real world current consumption from the max. When figuring how much fusing you need, just go with what the manufacturer specifies. If you're blowing fuses, you have other problems. Wouldn't it be easier to teach them something hat is universally applicable and more correct? It's pretty basic to just tell them divide the output power by the normal car voltage and then divide that by amp efficiency. From there just tell them to assume that Class A/B amps are going to be around 60% efficient at full power on test tones (not that that's real world but we're figuring max draw here) and that Class D amps will be around 75% efficient.

By dumbing it down you're not helping anyone to really learn anything; you know the whole give a man a fish, teach him to fish thing.

My real question is, "why does any of this really matter in the real world?" The current draw is going to vary wildly with every install and user even if we're talking the same amp wired into the same load. If the point is to ensure that the charging system is up to snuff, in most cases, assuming worst case current draw would lead to a lot of electrical upgrades that would be a waste of the customer's money. If electrical upgrades are more targeted to the use that the system will actually see from the owner, their budget can be more wisely applied to increase their enjoyment of their system.

For example, the system that I'm working on right now would require some serious electrical attention if we looked at worst case. 4 amplifiers and 1400+ watts on paper. However, since I know my listening habits, both music type and volume level, I know that I will be fine with some basic efficiency upgrades to the factory charging system and I'm adding a small secondary battery as a little insurance against light dimming for the rare occasions when I turn it up a bit.

That kind of instruction is what I think most shops could benefit from. Yes, that's difficult to get across if they don't understand basics, but giving them a crutch rather than teaching the basics (which they should darn well know anyway) isn't going to get them to the next level.

 

[CarAudioGuru 10+ year member]

And that is the kind of training I give them.

Remember I said that this was the starting point. Then I go into crest factor, listening habits, etc. How to test with volt meters, O'scopes, phase meters, RTA's.

I don't know how many car audio systems people have fixed or resolved on this forum, but I have fixed or resolved well over 10,000 issues - all by myself.

I tell retailers all the time, IF I can't fix it...you are ****ED!!!

And I have always fixed it (or figured it out)

And like you said with 1400 watts (even assuming Class D) full power current draw would be something near 163 Amps.

But since you (like me) actually listens to REAL music, then it isn't a real issue,

Because of Crest Factor(dynamic range). So assuming worst case and 10dB of Crest factor, then the current draw in car will only be continuous "averages" of 16 amps.

Piece of cake.

BUT...most people I have read (at least so far) on THIS forum are SPL guys. Well then the gloves come off and it is worst case scenario time.

Its now 163 amps of current draw.

I can say that out in the field, dealing with "Real world" in the "trenches" sort of stuff and seeing about 10-20 dealers a month in all markets of the USA, SPL is very low priority with our retailers.

Then again, we deal with typically middle to high end retailers that sell JL as their normal line.

But the few SPL guys they get are 90% of all their headaches.

I always explain "And, why are you surprised by that??".

Its Drag racing with sound (NOT music //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif )

 

[CarAudioGuru 10+ year member]

Its real simple. IF you listen to "music " (the REAL stuff, Fleetwood Mac, Doors, etc, etc) then there PROBABLY will be no issue.

BUT...if the consumer turning the knob is , well...a KNOB, and plays "Bass That Ate the Earth " type music.

Then the method I teach them is a close (if not closer ) than any other method used by anyone,

WITHOUT full on O'sope meter readings, Clamp on Current draw, etc. to get to what it really will be.

I know cause I use it everyday, with 100's of retailers to solve issues with them.

So I KNOW it works.

And my current draw method is simply adding the 50% into the equation up front.

So i don't get it, it is Ohms law??? I=P/E correct (but that is assuming 100% efficiency.

So why is my X2 such an issue??? 50% is what I have tested many many times with Class A/B amplifiers. In Car.

I try to help people understand and solve issues. I don't get what the problem is.

And I do it for a living. And get paid to do it.

End of thread for me.

 

[helotaxi 5,000+ posts]

I'm not saying it doesn't work. It does, but teaching them the right way rather than a dumbed down version would actually make them learn the why not just have an answer. Whatever.

 

[squeak9798 5,000+ posts]

And , Oh by the way, I was the guy who developed/designed the Phoenix Gold.MS/MPS/M and ZX series of amplifiers, and all the signal processors, Frank Amp N Stein, Reactor, Route 66, etc.

PG from 1989-2000. I was the founder of the electronics division.

And I do it for a living. And get paid to do it.

And you have how many patents? And Design and Engineering awards? I have 2 patents and 5 design and engineering awards.

You know your end of the disagreement is extremely weak when your first line of defense is to attempt to bring credentials into the discussion. A factual, accurate statement will stand on it's own without needing to be "qualified". A statement is true or false independent of the background of the author.

There is a member of several other forums who is one of the most intelligent individuals on the forums. He's been a member of the forums for nearly 8 years, and during those years has taken part in some intense debates. Do you know how many times he's brought his credentials to the table to defend his statements? None. I've only seen once where he commented in a debate as to what his credentials were, and that was only after the other person essentially insisted on it. And to say that his credentials absolutely shit stomp yours is an understatement. Yet you haven't even gone 2 weeks without trying to pull a credentials trump card.

Here are a couple of his quotes that I think you should heed, as they seem to summarize your end of the debate;

in science, credentials mean exactly nothing. I've got a tall stack of them myself ... comparable to just about anyone's in the biz ... and they amount to precisely zip.

This one is rather ironic, given your username;

there's no room for gurus in science ... self-proclaimed or otherwise. "Because i said so" is never a valid scientific argument ... and never will be.

Displaying credentials in a debate demonstrates either a lack of understanding, a lack of intelligence or an abundance of ignorance. They never make a statement more accurate than it is, based on physics.

As Tommy Lee Jones says in MIB; Cool, whatever you say, slick, but I need to tell you something about all your skills. As of right now, they mean precisely... dick.

 

[roarzorz 10+ year member]

Arguing on the internet like a kid? I don't care what credentials this guy has or how smart he is he has the attitude of an 8yr old. You won't last long here with the "I'm smarter than you attitude".

The OP should check into the Sundown SAE-1000D or I strongly suggest the new SAE-1200D.

 

[CarAudioGuru 10+ year member]

Have a nice life.

The "nic"name was bestowed onto me by my fellow employees, and retialers . In the car audio industry I am known by this nickname.

They had it printed on my business cards for 10 yrs.

Again. All I am trying to do is help people, and you want to make it incredibly difficult.

I'm trying to being logic and reason to the table. And everything I said is factual, tested, real world.

You've not responded to any testing that you've done. Its the vague "to many variables" to use. Which I agree too also.

But I bring it down to something real, something you can count on and works every time I give out my Ohm's law formulas that are spoken in a different way, but are exactly the same (except for the X 2 deal for 50% efficiency) And I tell the retailers it is Ohms law (but with 50% added because of efficiency)

So ..what is the deal?? I don't get it. You just want to argue to argue???

And your "handle" is Delusional Psychotic

How apropos

(werewolf -aka Jeff is probably who you are talking about. Great guy, but a PURE engineer, we have many "debates" on amplifiers)

 

[TurdFergueson2 5,000+ posts]

Feels like one of those deadener debates. You could have just suggested some PG stuff Guru

 

[CarAudioGuru 10+ year member]

This whole argument is about current draw. And "my" formula.

First isn't the formula I=P/E correct?? And that is Ohm's Law?

If so isn't that the same as Total Power divided by DC volts???

Yes or NO??

If so that is assuming 100% efficiency. which is impossible.

So all I did was add the X 2 (for 50% - assuming worst case)

So Total Power X 2 divided by DC volts.

And I get jumped on ??? For using Ohms Law? what gives????

Because I worded it different?

(Sorry about the credentials thing, my bad. But I do think it important to know that

I've tested this stuff in 1,000 of cars. Probably 10,000 cars over the last 35 yrs.

So I think that is important to know. Just as an FYI)