Speaker selector that can handle a fully balanced/differential output amplifier.


Hi everyone,

I'm in need of some help. I need a speaker selector switch where the speaker negative posts are separate. They can't be tied together or else my Red Dragon M1000 Mk1 monoblocks will shut down. From corresponding with Ryan over at Red Dragon Audio I have to ensure the selector can handle a fully balanced/differential output amplifier (both the Postitive+ and Negative- speaker terminals are hot and carry the same voltage).

I was hoping that the Adcom GFS-3 could do the job but it doesn't seem like it as we can't determine if the GFS-3 has shared negative speaker posts or not. If an Adcom GFS-3 owner could confirm what the layout is that would be great. If anyone has selector switch suggestions that would be great too. I can't afford the The AVA ABX Comparator Switchbox that was recommended.

Thanks in advance.


128x128jedinite24
Thanks tls49 for the suggestion. I will review and send it over to Ryan at Red Dragon Audio for verification.

To Al., MANY THANKS for the in depth reply. I had no idea to connect the monoblocks like you stated. After reading your reply I realize now how much details I left out and lack of specifics. I was intending of treating the monoblocks as if they were a single chassis 2 channel amplifier. I was just going to plug the left and right channels to a single input set and then have 1 set of outputs to a pair of Ohm Walsh MicroTall SE speakers and another set of outputs to a pair of Elac Debut B6 speakers. I just wanted to switch in between the speakers at a touch of a button when everything was powered off. I wasn't going to do any A/B testing though.

Thanks again.
I don’t know of any, but if your intent is to select which of two left channel speakers is connected to the left channel monoblock, and which of two right channel speakers is connected to the right channel monoblock, and assuming you can find a selector that is suitable in all respects other than having common negative terminals (including the ability to handle the high power levels that may be involved, given the high power capability of your amps), you might consider using two such selectors, one for each channel.

That approach would result in the negative output terminals of the two monoblocks never being connected together, and the fact that the negative terminals of the two speakers on a given channel would always be connected together (and to the negative output terminal of the corresponding monoblock) won’t matter.

If your intent is to choose which of two amplifiers is routed to a single speaker on each channel, however, it would of course be a different story.

Just a thought. Regards,
-- Al