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Switch between amps

I regularly use an Ayre VX-5 Twenty stereo amp to drive KEF Reference 1s, but would like to be able to switch occasionally to a pair of Cary 572SE tube monoblocks.  I envision a box that has two pairs of speaker input connectors and a single output connector.  It would need to provide some sort of load for the amp not used.  In my case, an added complication is that the Ayre has provisions for bi-wiring whereas the Carys do not.  I doubt such switch is available, but I'm not sure.  An alternate path is to drive a pair of KEF LS50s with the Carys.

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imhififan
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I regularly use an Ayre VX-5 Twenty stereo amp to drive KEF Reference 1s, but would like to be able to switch occasionally to a pair of Cary 572SE tube monoblocks.
You need to be very careful to choose a switcher using on a fully balanced power amp like the Ayre VX-5 Twenty stereo amp, it must be able to switch both + and - speaker terminals! Some selector like the Bryston 2WSB WON'T work because the "-" terminals are connected internally.

  http://old.bryston.com/PDF/Schematics/SSB2_SCHEMATICS.pdf

In my case, an added complication is that the Ayre has provisions for bi-wiring whereas the Carys do not.
The solution is using 2 stereo switchers, one on each channel.
On the Ayre side, use the "R" speaker terminal for high and "L" terminal for low.On the Cary side, using a pair jumper cable connect the R and L terminal together.
It would need to provide some sort of load for the amp not used.
Yes, it's a good practice to protect an tube amplifier and some SS amplifier.
 
I doubt such switch is available, but I'm not sure.
That's the reason I built my own.
https://systems.audiogon.com/systems/8685 
High quality speaker relay is the key! I highly recommend relay with bifurcated contacts like the Amplimo LRZ.

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