I've got a Shure sm57 mic and its great for recording electric stuff with my amp turned up loud, but when i'm recording acoustic guitar i have to turn the input volume on my multi-track right up and i get a load of noise and hum, my question is do i need a condenser mic for recording acoustic stuff and vocals? like are they more powerful or something? sorry if this seems like a noob question cheers
what are you running your sm57 into? it should be an awesome acoustic recorder, assuming you're going into a preamp?
hmm not sure if that comes with a preamp or not, but any half decent preamp should be giving you a good enough amount of volume to give you a quality sounding acoustic recording
I can't see any reason with ur set-up to indicate a problem with acoustic recording.
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But given a choice, I would use a decent condensor (though probably not a large-diaphragm.... probably a medium diaphragm condensor if I had one) over a 57 as a "first-choice."

Could I get some more talent in the monitors, please?

I know it sounds crazy, but try to learn to inhale your voice. www.thebelcantotechnique.com

Chris is the king of relating music things to other objects in real life.
Realize you need to put the Sm57 relatively close to the sound source, like within 3-5 inches, to get good input levels.

Condensers aren't more "powerful", they just pick up sound from further away, so can be used for more far and ambient micing needs.
Sounds like there's something wrong there, that shouldn't be happening. 57's aren't the best mics for acoustic, but it should certainly do the job. Have you plugged it into a different input to see if they all cause this to happen?
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