You need a pre-amp for mics (sm57's and 58's included). Mics have a low signal output called a "mic level". The recording devices need a "line level" signal strength. If your audio interface does not have built in pre-amps, then you need an external one. Condensers need 48V "phantom power" -- and then usually more gain through a pre-amp (most pre-amps have both the phantom power and then additional power boosts).

Can you record with a dynamic mic without a pre-amp? Yes, but you have to fire up the gain too high and you introduce too much noise. I've done that. Here's a link to a dealer that sells a lot of high end pre-amps: http://www.odysseyprosound.com/microphone_preamplifiers.php

While cheaper pre-amps work fine to boost the signal, the better ones will have less noise. Also, people swear their pre-amps can impart warmth and character to the sound/performance of a mic.

Last edited by Kevin Emmrich; 02/22/12 01:18 AM.
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