Car amplifier for boombox?


2019-10-14 4:05 pm
Hi, first post here!

So I've got some old car audio stuff collecting dust, and I was wondering if I could use some of it to make a boombox. From what I've read car speakers will do ok, but I haven't found much on car amplifiers. Anyway, I think what I've got is a rockford fosgate p4004, 4x50w @4 ohm.

Any guess as to how it would work compared to one of the small amp-boards I see people use when they build stuff like this? Off course I'll need to add some kind bluetooth separately, and a volume control.



2019-10-14 4:05 pm
I see lots of "boards" refered to as either class D or chipamps. The ones I've seen range from $10-50.

By more efficient I understand I'll need a much larger power supply with the AB amp than a class D board.

If my AB amp is 4x50w =200w in 4ohm, and I stay above 4ohm with my speaker load, will a 12v 200w power supply suffice? (or should it be a 14v ps?)

There are a lot of blanks, It's been 10-15 years since I was into this.

Perry Babin

Paid Member
2003-11-20 11:01 am
Total current draw will depend on the efficiency of the amplifier and the power produced by the amplifier. The power actually drawn by the amp depends on the volume level. Barely audible, maybe 1 amp of current draw. At full power, maybe 25 amps.

More efficient means less current draw for a given power output.

Chip amps typically have been class B or AB but can be any class. CHIP generally means that the IC drives the speakers directly with no power transistors needed.

12v or 14v isn't really important for the 4004. For amps without a switching power supply, it could mean a difference in power output.