I'm looking at amps... and they give different power outputs... and then have a voltage next to the amp. i'm guessing that's for the power you give it from the battery? I thought most/all car batteries were 12V.

thanks for the explaination.

Mark

A car battery rests at 12volts but when running the alternator produces 14.4volts and the electrical system sits there.

Reality: some cars differ slightly in both rest and running voltage but these have become something of a standard in car audio.

The voltage rating beside the power rating is to tell you at what volatage the amp makes rated power. For instance, if an amp is rated for 100 watts at 14.4 volts, it will probably produce less power at 12 volts. It just gives you a point of reference for power ratings.

okay... so while the car is running... you get the power out at 14.4V... and less power when the engine isnt' running...

If a sub takes 300W rms... how little power can you give it.. and have it still operate?

When a car is running, you got apparently 13.8 volts and not 14.4. Where that 14.4 volts standard come from? I don't know but that's the reality.

Yes you got less current to your amps when the car is not running at least you buy amps with fully regulated power supply like JL audio Slash serie, PPI, Soundstream and probably others. This technology is more costly but it give you the advantage of having the same power all the time. Car running or not.

If a sub takes 300W, you can give it 10 watts if you want, it is still gonna operate. You simply not gonna hear it! If you want to reach a good level of performance with your sub, It is recommanded to run it with an amp which have at least the nominal wattage power of the sub per RMS not Peak! e.g. A 300 watts sub should be push by a 300 watts RMS (mono if possible) amp at the impedance of the sub. Having more power never hurt. That let the amp having more headroom and run with ease.

lappy

My VW gets 14.8 at the amps. Every car is lsightly different, and it will vary when accessories are turned on.

batteries are there to start the car and the alternator actually provides the electricity when it is running. the alternator can go as high as it needs to to run the vehicle. so it might run at 13.8 it might go as high at 14.8. the average is 14.4 approx. so they measure it at such. but if you played your system with the car off you'd just get the battery voltage which could be low. so they give you that rating also. battery and alternator voltages. both are apprx. and each car's voltage may vary depending on what is on and off at that individual point.we burp our spl car at 15.9 volts. others in extreme burp at 17.9. they do this to bring the voltage up to max before the amps reach thier limits or the limits according to the rules. but they all get this voltage from the alternator. they simple bypass the controls that are set to 14.4. this is not recommended for daily driving. and is highly recommended for spl.

[ November 08, 2004, 09:35 PM: Message edited by: Team Shadow ]

1 watt, even less.
I've played subs on mini-system before. 40 watts max 2 channels combined. They were seeing about 8 Watts RMS and played fine. The subs were rated @ 150 RMS. I just couldn't expect them to play LOUD with that kind of power. They just filled out the low end of the mini-system.