Two Amplifiers With One Set of Speakers

I currently have an Integra receiver for my home theater setup and a tube amplifier for music. The issue is that I only have one set of speakers. My current solution is to have two sets of speakers cables that I switch at the speakers. It really only take a minute or two to make the switch, but it's enough that I'd listen using the tube amplifier more if it were a more simple switch. I'm thinking about using a speaker switch box and just hooking it up backwards. If I can hear a difference then I would stay with what I am currently doing, but I suspect that it will work just fine.

Any recommendations for a switch box? I'm looking for inexpensive. I would probably get a really short run of Blue Jeans Cable to minimize the length between the two amps and the box and then use my current run to the speakers.