Woody wrote:

Maplin JK30H @ £3 each. You only need to switch the live side of the
speaker feed - the ground sides can stay connected in parallel
throughout.


Though the OP should check (with a DVM) before doing this, that that
negative speaker outlets of *both* amplifiers concerned are actually
internally connected to ground. Ye don't want to upset a
bridge-tied-load amp, if ye have one of those in your setup ...

http://en.wikipedia.org/wiki/Bridge-tied_load

--
Adrian C