I realize that vocals and amps require different mics but so far I have been using dynamic mics for both. I'll just focus on amp mics for now because that is what I am mainly concerned with. I have been using 2 sm57's for guitars w/ an old junky interface (everything sounds dead and muffled, but I figured it was the interface/pre-amps) and had planned on continuing with the firebox until I read that these mics are not good with this interface. I just want to get the best possible sound I can get with this new interface. I have researched a million dynamic mics, but I am curious about what mics will be the most compatible or the best with the pre-amps on the firebox. I have read a bunch of threads and mic comparisons, but I am wondering if there is a more specific mic I need to maximize the potential of the firebox. I can afford about $100 - $300 right now, but if there is a mic that will be perfect for me I will spend more.