I am familiar with speaker switches which allow multiple sets of speakers to be driven by one amp. I even have one of them. However, I have not seen a switch that allows one pair of speakers to be attached to two amps. Only one at a time, I don't expect or want both amps to drive the speakers at the same time.
The need is a little weird and other solutions might exist. I gave my son my old Onkyo 605 AVR when I upgraded it. He is now planning to buy a 5.1 speaker set to use with it. He has the TV at one end of the lounge, a desk at the other end, and the sofa for TV watching in between. He plans to put the rear speakers on the desk. He would like to use them as rears when watching TV but zone 2 for stereo when working at the desk. So, connected to the same amp in both cases but to different terminals. Connected to the surround terminals when acting as rears and to zone 2 terminals when acting as stereo alone.
I suggested that he bought an extra pair of speakers and put the surround back ones on the desk. They would then use the same terminals as zone 2 and they could be switched from one function to the other with settings in the amp rather than fiddling with the wires. He likes the idea but his budget does not support that yet. He would also need a pair of stands for the surround speakers. A feature of the current plan is that the desk acts as the stand.
The need is a little weird and other solutions might exist. I gave my son my old Onkyo 605 AVR when I upgraded it. He is now planning to buy a 5.1 speaker set to use with it. He has the TV at one end of the lounge, a desk at the other end, and the sofa for TV watching in between. He plans to put the rear speakers on the desk. He would like to use them as rears when watching TV but zone 2 for stereo when working at the desk. So, connected to the same amp in both cases but to different terminals. Connected to the surround terminals when acting as rears and to zone 2 terminals when acting as stereo alone.
I suggested that he bought an extra pair of speakers and put the surround back ones on the desk. They would then use the same terminals as zone 2 and they could be switched from one function to the other with settings in the amp rather than fiddling with the wires. He likes the idea but his budget does not support that yet. He would also need a pair of stands for the surround speakers. A feature of the current plan is that the desk acts as the stand.