I'm trying to hook up a really cheap 700watt amp up to my box with 2 12"s. My old amp fried and I think I'm going to redo everything this summer, but in the mean time I'm throwing in this crappy amp I got for free (the company's web page isn't even online anymore) ((amp is a mobile authority ta-3001)).

I hooked everything up, the amp lights up, but no sound is coming out of the speakers. I'm wondering if it's safe to use a small home multimeter I got at radio shack to check the levels of the wiring.

I figure I can definitely check the input levels going to the amplifier with it, as they should be pretty low, but how can I check if the wires going to the subs are sending out any signal? I'm worried they'll blow the multimeter if they're actually trying to send a signal to the subs (I need to check if maybe the polarity is wrong on the subs, I assumed they were set up so that black is ground and red is positive, but I had Al and Ed's do it so they probably were retarded about it).

So what can I do to start troubleshooting this? Also, for some reason the power connections on the amp are tiny screws, there's no way to wrap a 4ga power wires around them (so I had to cut off half the wire and just wrap a small section around). If I solder the end of a 4ga wire to a small u-shaped connector (spade?), will that small piece of metal be able to handle that much power?