Using a Car AMP as Preamp on Receiver?

You can't use any amp as a preamp even if it is a car amp. If you meant using the head unit - well - maybe. But not a pure amplifier.

I've been using a 10" auto sub installed in a small sealed enclosure for the past few weeks. I like to tinker! I'm driving it with a 240 watt Dayton plate amp driven by my Harman Kardon 3390. I've been very surprised at how well it sounds for music. It is very detailed and does not exhibit the boom that is so prevalent in today's car audio. Most of those are ported enclosures that allow booming bass - it impresses the street corner crowd but sounds like crap. It plays down to 35hz before rolling off - nothing to speak of past 30hz.

Get a decent power supply - a computer power supply might be ok if you don't draw too much from it suddenly - they are made for steady loads - not shock loads. Some of them are capable of cranking out 20 amps or so. Find one with a single rail - meaning all the power comes off a single side. Some are dual rail - they have in effect 2 12v sides and less amperage will be available per side. Combining them would be instant fire and sparks.

It isn't going to impress anyone with its movie performance but for music they do quite well.

My sub is an Infinity single coil 4ohm. The Dayton amp has no problems getting to work well. It'll be going into my Karmann Ghia after it gets painted over the winter. I've also got a JBL 300 watt sub amp that'll drive the sub when it gets installed into the car.

Depends on the connections to the amp. Is it RCA or speaker level inputs?

You'll need a good 12v power supply - or get a 120v plate amp and do it like I'm doing. I'm listening to classical music as I type this - sounds wonderful.

You'd be better off just getting a heavy duty 12v power supply. It'll have a single rail supply. Get one capable of at least 15 amps. 500W/12=41 amps. Rockford is guilty of puffery - I doubt the amp puts out 500 watts - probably 200 or so continuously on a good day. 15 amp power supply should suffice.

How does the amp get the subwoofer signal? RCA or speaker level inputs? Is the amp a mono-block - 2 channel - 4 channel?

Get power supply for the rockford amp....You need to make a jumper from the remote input to the +12 volt to turn the amp on

plug rca of sub pre out of reciever to the input of this amp. Hook woofer to the amp.

It will work

I was thinking something like this.

Even better would be this.

You'd have no power supply problems. You could get the same one I'm using on the Infinity 10" right now. Don't be fooled by the 240w rating - it'll run circles around your car amp.

Go with KNUCKLEHEAD 90's recomendation.

I was going to suggest something from Pyle they make units like that as well for bench testing car equipment. We used something like this pice to power a car stereo mounted in a hot tub a few years ago. The car head unit and built in speakers worked great for a cheep sound system that was built into a hot tub

I think even radio shack has bench power supplies for car audio...

Forget the computer supply I dont think youll get enough amps from it.

Hell a car battery charger would even work as a power supply.....

Do not use a computer power supply especially a $20 one that claims 500 watts. First off that is all rails or all voltages driven to a given level. ie. there are 5volt 3 volt multiple 12 volt rails. If you plug a 400watt device into one rail and that rail only has 100 watts that is all you will get from it or the power supply will try to provide the power and could catch on fire. You would need a very good 800-1000 watt computer power supply to actually make about 500 watts on a single rail that would output to your sub... much cheap and better is a dedicated 12 volt supply.

if you look at the data plate for the power supply you want to buy it has 2 X 12 volt rails at 20 Amps each i.e. 240 watts per plug/rail. and a max of 384 watts for both 12 volt rails i.e. bywiring the amp, which I am not sure would even work with a computer power supply.

Remember this is MAX not what it can handle for a long time.

just sell the speaker if you are happy with your home system. a Car Sub is not meant to do the same thing as a home sub... what is the freq responce of this sub? if it doe not go down to at least 30Hz or lower it is only going to hurt your system not help... assuming you have a decent sub all ready.