Efficiency of different amplifiers at different loads

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ReneBMW
Posts: 88
Joined: Mon Mar 01, 2010 1:18 pm

Efficiency of different amplifiers at different loads

Post by ReneBMW »

Hello.

As I'm just curious I would like to know how efficient the pg amps are/where.
Especially the older ones, like the zpa.
I know that a clas a/b amp has a +/- 60% efficency, but decreases as load gets lower.
Now, I have a modified zpa 0.3 running 2 ti212d2, what will efficiency be of a zpa on a 2 ohm load?
Just to get an idea I would like to know from more amps.
This will come in handy calculating how much power I can get out of my 140 amp alt or how big my alt needs to be for the desired power.
Hmmmm, atm it's loud enough for me and plays perfectly, but I have a voltage drop to around 13.2 volts from 14.1...
Kirghiz
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Re: Efficiency of different amplifiers at different loads

Post by Kirghiz »

If I don't have hard numbers for the current draw I plan on roughly 50% and use the birth sheet rms power to figure it. If you are running 600 watts rms, double that and divide it by 12 (voltage), (which would be about 100 amps). Keep in mind that it won't be a constant 100 amp draw, it'll only do that on musical peaks. That system of figuring will get you close enough, because again, it isn't a constant draw, and you can't hit it exact anyway. Even if the efficiency is lower, using 12 volts as the voltage will account for lower efficiency, because you are likely feeding the amps 13-15 volts anyway.
Being loud without good sound quality is pointless, but having good sound quality without being loud is also pointless.
ReneBMW
Posts: 88
Joined: Mon Mar 01, 2010 1:18 pm

Re: Efficiency of different amplifiers at different loads

Post by ReneBMW »

The music i play is hardstyle, house with fast hitting beats, I see the voltage going down every time the bass hits, not only on low bass, also on midbasses...
I have the ti elite 5 active on a zpa 0.3 and it uses all of the 150 wrms.
When I play rap (hate rap but I like the bass) with longer bass notes I see voltage drop initially, to recover realy fast.
I understand that it's almost impossible to keep voltage steady at 14 volts, especially on music peaks, but on a analog gauge it doesn't look like it goes down as much as with a digital gauge.
I have 2 gauge from front to rear, about 3 meters, go to my alumapro cap, then fuse holder all with 4 gauge.
It's not the "big 3", but I know that 2 gauge is enough for the distance.
Still it keeps me awake that I see the voltage drop.
No dimming of lights, no amps that get to hot, nothing, just the gauge.
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dvnt88
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Re: Efficiency of different amplifiers at different loads

Post by dvnt88 »

Doing the big 3 along with a 2nd battery will definitely help ...but you may want to run 0g wire (OFC ...not the CCA crap). You'll notice quite a bit on the voltage drops as well as feeding your amp everything they ask for without putting too much stress on ur electrical system.
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Kirghiz
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Re: Efficiency of different amplifiers at different loads

Post by Kirghiz »

As a general rule, anything more than 100 amps worth of amplifiers is more load than you should put on a stock electrical system (battery and alternator). You can do it, but you'll burn out alternators every six months or so, and the voltage drops will clip the amps. Heavier wire and even a big 3 can actually hurt you because they allow the amps to pull the current that you don't have even faster by creating larger pathways, which compounds the problem. Extra batteries can offset that a bit, but at the end of the day there is no replacement for more alternator/s.
Being loud without good sound quality is pointless, but having good sound quality without being loud is also pointless.
ReneBMW
Posts: 88
Joined: Mon Mar 01, 2010 1:18 pm

Re: Efficiency of different amplifiers at different loads

Post by ReneBMW »

Dont know what CCA is, but its all OFC.
Then the only thing to do is have my alt upgraded, and i dont have a clue where to have that done in the netherlands, but i Will start my search.
The alt I'm currently running is in my car for a year now
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Drock
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Re: Efficiency of different amplifiers at different loads

Post by Drock »

CCA= Copper Clad Aluminum wire.


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Mr. Wild
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Location: Finland

Re: Efficiency of different amplifiers at different loads

Post by Mr. Wild »

Here's some measurements of lots of amps including PG. They haven't measured any ZPAs but you can find efficiency of some old PG amps:

http://amp-performance.de/106-von-Alpine-bis-Zapco.html
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M50, MS275, MPS2500, ZX450, ZPA0.3
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