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Question:
I just went outside with a multimeter and measured the voltages going to the amp. When at low volumes, the amps both read 14.0v, but when I crank it up to the max (450w rms total), the multimeter goes from 12.5 to 13.5. Is that acceptable, or is that what killed my Soundstream amp? What really worries me is that I plan on adding 75w RMS component speakers, so the 2ch amp will be pushing 150w instead of just 50w, bringing the total RMS to 550W. I'd hate to see how much the voltage drops then

If the gain is not a wattage control as kiki stated earlier, your putting the same amount of watts to those speakers you have now as when you upgrade to the 75rms speakers correct? Wouldnt that also mean that the voltage would stay the same?

it dosnt matter what speakers you have hooked up to your amp it is going to give the same voltage if the ohms are the same, changing your gains does not regulate voltage. and yes get a differnt battery.

sinister audio wrote:it dosnt matter what speakers you have hooked up to your amp it is going to give the same voltage if the ohms are the same, changing your gains does not regulate voltage. and yes get a differnt battery.

I of course may be wrong, but I don't think that's true. The gains do regulate how much voltage goes to the speakers, which in turn regulate how much the amp pulls from the battery\alternator. If that wasn't true, I wouldn't dim when the bass hits and the speaker voltage shoots up, rather it would start as soon as the radio was turned on.

aggybong wrote:I of course may be wrong, but I don't think that's true. The gains do regulate how much voltage goes to the speakers, which in turn regulate how much the amp pulls from the battery\alternator. If that wasn't true, I wouldn't dim when the bass hits and the speaker voltage shoots up, rather it would start as soon as the radio was turned on.

Well, technically no. That is just really the result of what it is really doing. The gain attenuates the inputs from the preamp in only. That determines the level of the signal, basically like turning up/down the volume on the HU.

The signal will have more clarity with the gain set close to the optimum than with the gain set lower.

cool aggybong, i see you in TN also :-P

"My 1995 Toyota Camry has an 80amp alt and my lights slighty dim when I'm only at 450w gain wise, when my amps can handle near 1000w."

that is what gave me the idea you didn't understand gains ettings. using gain level to indicate power output from the amplifier.

if you read the FAQ section, there are a number of alternator sellers listed in the company URLs, many of whom can supply the alternator you're after.
a 200A alternator would be fine as well however, as the alternator will only supply as much current as required by the devices drawing current. 200A is a peak output rating, and anything between that rating and what you're actually drawing will just be reserve current available if it's needed.
you do want to be careful when purchasing alternators though to get one that has a good current output even at idle. many cheaper ones will have high ratings (often cold ratings if not specified) but will be significantly lower at hot rating and at idle, which isn't much good to you unless your car is wound up to at least 2500rpm or higher depending on the alternator.