What is the difference in the sm 57 and sm 58 mics?
Sonic, clarity, voice and from the recording of instruments and
sound response?
They're the same mic, except the 58 has a pop filter. If your
vocalist pops Ps, then go for the 58. I believe the filter also
rolls off a touch of high-end, so if you're not recording a P popper,
the 57 will be fine and have a touch more of the highs. (Of course,
you could get the 58 and then unscrew the ball at the end, which will
give you a 57, more or less, but the capsule will be unprotected.)