This thread is rather timely for me. I just ordered an Audix i5 and a Sennheiser e604 (upon Nathan's recommendation). They should both arrive later this week and I plan to do some comparisons with them through either a ME1NV or an API 3124+
on both snare and guitar. In the past I have tried the following on snares with varying results:
SM57--we all know the sound SM57
with transformer ripped out--bigger low end and more open, smoother high end than stock, much less output
Shure 545 Unidyne III--didn't cut like a regular 57
Oktava MC012 with pad--used this on a jazz session with brushes once
Beyer Soundstar MKII M400--much fuller than a 57, nice high end, with nicer bleed from hi-hat and kick
Sennheiser e609s--fuller in the bottom end than a 57, with a more pleasing and better placed midrange boost, good rejection of hi-hat due to super cardioid pattern
Radio Shack 330-3032--looks like a Sennheiser e604, no low end to speak of, broad midrange hump, hyper cardioid pickup...sounds weird soloed but great in the mix; you can really get this mic close to the drum and not have the low end be out of control, it's pre-EQ'd.
Lately I've been choosing either the modded 57 or the Sennheiser e609s, typically through my API or Vintech 1272 preamps. I'll have to let everyone know how the Audix and the e604 stack up.