okay, so I run two mics into a mixer, and then into a guitar amp (because we dont have a p.a.)
my mic gets a lot more feedback because it's got more hi's than my bass player's mic
so, I was wondering, is there a pedal or something I could get to reduce feedback?
You need a P.A.

Also, make sure the mic isn't pointed at the front of the amp. Have the amp in front of it, or face the amp.
^what he said

Dont have the microphone pointing at the speakers. thats the main cause of feedback
point the mic away from speakers, and reduce the treble. You mention that you run the mics into a mixer, then into the amp, so the place to tweak the EQ is the mixer. Just reduce the treble a smidge, and reduce the gain aswell. that usually sorts it.
Quote by Dave_Mc
how do those marshall handles compare tonewise to, say, mesa handles?

Owns a Blackheart Little Giant...
well, the mixer doesn't have much of an eq, and the eq it does have effects both mics...
I'll lookinto getting a pa, but would a compressor pedal help at all for now?
You run a powered mixer into a guitar amp?

Quote by sargasm
There are no genres in metal that end with "core."