On 22 Apr 2006 15:43:18 GMT, uson wrote:

Other than buying a preamp with such a switch, it would seem a
relatively easy device to design. Needs to be completely inaudible, and
avoid switching "pops". My ears are very sensitive to correct polarity
(in some recordings) but my pre-amp does not have a switch, and its a
royal pain to reverse the speaker leads.

The gadget can be a simple but good quality switch IF your
preamp-to-power amp connections are balanced. If not, you need a way
to invert polarity, either an active circuit or a transformer.

Kal


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