not a lot there is an age old debate about them. they are like a battery designed for just one big bass note then they are empty. some people say it helps the sound of their car system others say it puts even more strain on the altenator and cars electrics and does more harm than good!
Think it would be impossible for them to make anything sound better. That would be down to the speaker choice wouldn't it.
I was under the impression that they helped the battery and alternator. Not put pressure on it. Idea is that the are charged like a battery but only used when needed. If the music system hits a high peak that would require more power, then it would take the power from the cap rather than you alternator or battery.
^^don't quote me on that ^^
I have got 3 amps in my car. 400W 2ch to power my 17cm componants at the front. 600 or 800w 4ch to power the componant 6x9 for the back and 600w built into my 10" base box. Sound well and have no problems with electrics or starting.
TOUCH WOOD
And No, I don't use a power cap though my boot need a good tidy. Too many wire
"Old enough to know better, Young enough not to care"
In theory they are just a BIG capacitor to help deliver more current when needed by the amp. But if the power feed wire has been sized correctly (And the amplifier too) there should always be plenty of current available. As tom said, just another shiny thing that looks good - does S.F.A.
Whats your opinions on all this audio nonsense tom ?