Your mentioning that made me realize that I could do the same in order to compare two receivers I have.
Although I would also need a speaker source switching ability, so I could at the same time pipe the second recr through the same speakers I had just been listening to the other one through! (I might have a switch that could do that....do I????)
Just make sure you have true A/B switching as you don't want both signals going to the speakers even for a second.
I use a TEC TC-616. There are other alternatives out there but none real cheap unless you make one yourself.
Gary

