Re: difference between sm58 and the beta version?
The Beta 58 has about 3dB more output, and a slightly more open top end. (ie, different frequency response curve) It also has slightly better feedback rejection characteristics. The Beta's are good mics, and their improvements are in keeping with the advances in other areas of sound reinforcement. I've got a Beta 57 for recording guitar amps and to have handy for gigs where there isn't a FOH guy. Good mics.
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