Sub/Amplifier Problem

I recently recieved this sub/amp setup from my uncle for my birthday. 600W MegaVox Competition Amp and 2 x 10" Marathon subs in a Marathon competition sub box. I have a 200W power supply that I used to test them as they are 20-25 years old. When connected to the 200W (12V @ 18A) power supply the subs could play sound (used an RCA to 3.5mm adapter that came with it) but was dropping out, which I assume is to be expected considering I was running a 600W amp off a 200W power supply. After this I installed them in my mates car ( AU Falcon, his wiring was all setup as he has subs of his own) by taking the wiring from his subs and connecting it to mine. When the car was started the amp powered up, but wasn't able to get any sound either from the head unit or the 3.5mm jack adaptor. Checked the voltage running through the power input and it read 14 Volts (normal as AU Falcons charge at 14V apparently). after fiddling around trying to get it to work i took them out and hooked them up to the power supply and it was back to being choppy but could still get sound.


Any help or insight into why I can't get sound from the subs in the car but can off a 200W power supply would be greatly appreciated


Cheers, Blake

(Cant upload photos files too high res) - https://drive.google.com/drive/folde...E-?usp=sharing

Although I'm far from an expert, I have some experience powering car audio gear with a power supply, and was surprised how much output I got from FAR less than rated power (as measured by a DC clamp meter). Presuming your power supply puts out rated power, my personal experience suggests there should be considerable output - certainly more than "some sound" (which I interpret to mean barely any output at all).

Without a cogent theory to explain it (why there's no sound at all in the car, and why low/choppy output on the power supply) I'm guessing the amp is having issues. Maybe there's another completely unrelated issue in the car hook-up? Seems to me, judging by the power supply instance alone, that the amp is having issues.

I'd try running the subs on a known working amp, to see if they're the problem. Check them with an ohm meter first, to see if there are any issues. I'd also try running different sub(s) or speaker(s) on the amp and power supply arrangement, to see if it does the same thing.

That's just my $0.02. I'm sure others more knowledgeable than me will chime-in.

I was going to ask about the remote wire, but it looks like that's jumper'ed and always on.

I'm not sure if you need the jumper between the channels when you bridge them, but that seems unlikely to be the cause because it's the same on-bench and in-car.

You seem to be following all the right steps. I'm not sure about this one!