Car audio question

[Downunderwonder]

Here's a weird one, I'm thinking about taking a subwoofer to work each day in a different vehicle. I'm no car audio expert so hoping someone can steer me in right direction as to what amp I need.

I think the way to get what I want is to take input from rear speakers ( speaker level input )

I'm looking to pick up a cheap amp. Did I mention cheap? This is just for a bit of fun and to see if I can get a few extra tips. It doesn't have to be megawatts. 10V is heaps for the sub.

Amp needs to be able to high and low pass a sub power output as well as power the Toyota rear speakers with a high pass. Simple, right?!

Reading amp specs I can't tell if any particular amp will do that. I asked about a 4 channel one with high pass low pass bells and whistles and got told no, it doesn't do that, like I was some kind of idiot. Maybe I am barking up wrong tree. What's the magic key word to look for?

I'd be looking to set it all up so maxing the vol in the cab can't do any harm. At a guess the stock amps are 15 to 20W per speaker, leads to some more confusion. Amps with "speaker level input" quote input sensitivity up to about 6 or 8V. Assuming stock speakers are 8 ohm then the volts from the stock amps ought to be 10 or more.

[elgecko]

Huh?

Amplifiers are rated in watts, not volts.

[Downunderwonder]

Car amps are all over the show as to what impedance they are making the rated watts. Want megawatts from measily 12V power supply? Do it into a 1/2 ohm load.

Voltage doesn't lie quite as easily. Point is I don't need much.

[elgecko]

You CAN convert the rear speaker signal to line level to feed your amp input but it won't "power" the amp...if that's what you're asking.

[MJ5150]

If you are powering one sub, why do you want a four channel amp?

-Mike

[ggunn]

Originally Posted by Downunderwonder

Car amps are all over the show as to what impedance they are making the rated watts. Want megawatts from measily 12V power supply? Do it into a 1/2 ohm load.

Voltage doesn't lie quite as easily. Point is I don't need much.

I still don't understand. Where do you see an amp's output rated in volts? Watts is watts, whether it's 12VDC through 1/2 ohm (288W) or 120VDC through 50 ohms (288W). It's the same amount of power.

[Bob Lee (QSC)]

I wish power amp and loudspeaker ratings were in volts.