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I need someone that is very knowledgable about amplifiers to answer a question for me. Say you take two 1000 watt RMS amplifiers, As far as output goes of course measured in watts they are within 50 watts of each other, one amplifier in a certain car with, say, 2 subs does 145 db, and then you switch it with the other amplifier and your spl goes up to 147 with both amps reaching peak output at the same impedance. I've seen it happen and I want to know exactly what it is about that second amplifier that makes it push subs harder than the first one. The output is pretty close to identical but the 50 watt difference does not make a 2 db gap. Am I crazy or does someone know what exactly it is that isn't measured, Does it have something to do with amplitude, distortion, what? I'm trying not to pretend that I know a lot about amplifier design. Please help me out.
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Posts: 695 | From: Lynchburg, VA, USA | Registered: Jan 2001
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Are these two different brands? they could be within 50watts of eachother when measureing with a resistor, but totally different when givin a inductive load like a speaker.
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Posts: 1259 | From: Fullerton. CA ,USA | Registered: Oct 1999
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Yes, two different brands. As far as within 50 watts of each other I'm seaking of Birth sheets like RF , MTX, so on and so forth. I would just like to know what makes the difference between different brands of amplifiers that seems like even when they are putting out the same or similar voltage one is pushing the subs much harder than the other, or is it just something else going on as far as the amps reacting differently to the resistance fluctuating from the coil. Am I making any sense?
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Posts: 695 | From: Lynchburg, VA, USA | Registered: Jan 2001
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how about battery voltage, or signal voltage, some amps will produce more power at higher bat voltage, or another way to look at it, some will lose less power as the voltage drops.. and input signal, some amps require more signal to reach full power, even at higher gain levels.. if both amps are of good quality and really put out rated power, I'd say one of the above two will answer your question.
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Posts: 735 | From: Calgary AB | Registered: Oct 1999
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Do the amps really match up perfectly? These would all have to be the same(like on a birthsheet) for the amps to truly put out the same power: input voltage, impedance load(will change with frequency played), and unclipped(THD hasn't takin off) power.
My geuss?..... either one: one amp is putting out more power than the other(possible gains-adjusting issue), two: The environment inside the cabin was different(temperature, humidity, altitude, etc) when they were tested, but were they swapped out right away?
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Posts: 141 | From: lala land | Registered: May 2001
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This wasn't one instance in particular but multiple instances that I have seen since and before I started installing. I guess conditions could have changed. So basically, I guess what I really want to know is, as far as true output voltage, 1000 watts is 1000 watts and as long as nothing else changes in the system itself the spl will be exactly the same between two different brands of amplifiers. It just doesn't seem right to me, even with just my ears and no meter we have put JL 500/1 's and punch 800a2's in the same car and the 500/1 seems to hit just as hard if not louder. While the JL won't put out more than 600 watts or so and the 800a2 is doing 900 or so. I myself had 4 RF 15's in my car running 2 ohm stereo off of a punch 400a4 and a stock electrical system and hit a 140.9 with just a rap CD, I then took that amp out and put in two MTX 225ho's and ran them at 1 ohm mono(around 600 watts or so out of each amps), added an extra battery and 2 1 farad caps and hit a 143.3 on the same meter using test tones of my resonant Freq. It was hotter and more humid on the day I tested it with the RF amp. Is there not a difference in performance, watt per watt between amps. I'm not saying any of you are wrong, I just want to know what is making these differences. Thanks for bearing with me.
------------------ I can't make up my mind!!!!!
Posts: 695 | From: Lynchburg, VA, USA | Registered: Jan 2001
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quote:Originally posted by RWAudio: how about battery voltage, or signal voltage, some amps will produce more power at higher bat voltage, or another way to look at it, some will lose less power as the voltage drops.. and input signal, some amps require more signal to reach full power, even at higher gain levels.. if both amps are of good quality and really put out rated power, I'd say one of the above two will answer your question.
I didn't think about the pre-out voltage, that does make sense, that could be a huge difference right there.
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Posts: 695 | From: Lynchburg, VA, USA | Registered: Jan 2001
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Mainly the differance is true output at your spefic load and power. 3 db remember is theortical a doubling of power. so a 500 watt amp would be 3db from a 1000 watt amp.
HArd to beleive a 2 db if exactly the same true output.
The difference in birthsheets of the same amps is usally the difference in the transformer winding in the power supplies being a little bit different.
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Posts: 1147 | From: Rowlett, TX, USA | Registered: Jun 2000
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I think I'm starting to understand. So in reality a watt is a watt is a watt. There is no actual performance difference between brands of amplifiers that makes a difference on a meter. It really is all in the output voltage. Sorry, had some preconceived notions there that needed to be killed. Thanks for all of your help.
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Posts: 695 | From: Lynchburg, VA, USA | Registered: Jan 2001
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Bear in mind if your 145 and 147 came on two different microphones, or a different lane.......
Also- Check the voltage coming out of the amp (AC volts) with the same frequency playing and you should get comparable voltages if the power output is comparable.
ShadowStar
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Posts: 2578 | From: Somewhere In the Northeast | Registered: May 1999
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