I have two mics, an SM58 & a Rode NT1 and am using a Presonus Firebox for recording. I would be recording one input at a time and it would be primarily voice and sometimes acoustic guitar or amped out electric. Could someone please guide me which preamp would fit my budget of $250. I am finding the gain on the Firebox rather low with the SM58 but just about acceptable with the Rode NT1. The room I'm using for recording is reasonably well soundproofed and equalized. Thanks a ton in advance. I must say I stumbled on this forum a few days ago and wish I had found out about it earlier!! I also have a cheap Behringer UB802 Mixer which has it's own preamps. Should I forget about getting an external preamp and make do with the ones on this?