balanced power for surrounds

Do you mean an amp with "balanced inputs" or an amp with "balanced circuitry". You can find B for your B in the first category, not in the second.
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Well, all amps with balanced circuitry, like most of the Balanced Audio Technology (BAT) some Audio Research, and other more expensive lines, have balanced inputs to take advantage of their balanced circuit design. But many less expensive amps (especially these days) have balanced inputs to take advantage of the noise rejection of balanced (XLR) interconnects, especially if you want to have long IC runs in order to keep the amps near the speakers, which is the best way to do it IMO.

Manufacturers' websites (like BAT and others) describe the nature of balanced circuit design.
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Another thing (amazing!) about all Bryston gear, is it comes with a twenty year, unconditional, TRANSFERRABLE warranty.
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