Heres the situation - I have 2 classic Marantz receivers, 2500 & 2600 and one set of Studio 100 speakers. I do NOT want to use both receivers at the same time, but would like to have a switch to turn to change the reciver use. (Hate redoing all the wires every time.)
Use a Double Position Double Throw (DPDT) switch in a cheap box. Radio Shack sells them (part number 275-653 $4). This switch has the advantage of being center-off to avoid shorts. Don't use a speaker switch in reverse. They have impedence matching resisters and may damage your receivers.