If its (voice amplifcation with minimum feedback and is compact and portable.)
I think u can good with the radio shack one, less then 15 buck, small, and the feed back really depends on how and were u put the speaker in relation to the ic, i have mine at full vol and no feed back...
But wait around as others will chime in, Wyatt made a awsome system and a mod to the radio shAck that makes any mic work!!!
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