New To Garageband..., ART tube pre-amp as audio input? Options

[lyryck]

Hi,

I'm ready to use my garageband audio recording/editing software, and trying not to spend too much money. I need some kind of audio interface in order to input live vocals. Is it possible to use my existing stage equipment? For example, I have a great little ART tube pre-amp that I thought might work. If I purchased an adapter to go from 1/4" to USB I could plug my vocal mic into the tube pre-amp, and the tube per-amp into the audio-in on my powerbook. Or could I?

Curious.
Am I fated to own an mBox????
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