Amp switcher

Yes, any device you insert in the signal line will degrade the sound. The degree of degradation and your tolerance for it is unpredictable.

If switched accidentally while the tube amp may have even a little high voltage stored up may blow the output transformers.A poor connection in the switch may do the same.

Russound 2.2 AB is also a shelf mount unit like the Niles. The Russound is rated at 150wpc however. There is also a wall mount unit (1.2)
10 yr. warranty
14 AWG spkr jacks
79.00

Niles rated for 100wpc
86.00

those are the only two I've found.

I'd be curious to see if any load is applied to the unused amp.... and/or if either or both amps can be left on when not under load/use.

The power capacity of the Niles concerns me... and the speaker taps of the Russound bug me.

Thanks for your responses.

Catama: Your setup is similar to what I was looking to do. What kind of speaker cables are you using, and at what length(s)?

Stanwal: I'm sure you're right, and as you said it's all a matter of degree. Which is why I'm wondering if anyone who has actually used it could hear an audible difference, regardless how slight.

Hifitime: My understanding is that the DPS-1 only has one button, therefore it's not an a/b scenario. Not sure whether this solves the problem you refer to though (save for the device being faulty). Here's a link to the device:
http://www.nilesaudio.com/product.php?prodID=DPS-1&recordID=Source+Switching+Systems&categoryID=Automated+Switching+Systems&catcdID=10&prdcdID=FG00003

Regrettably there's not much detail offered, and the manual states even less. If you (or anyone else) has any additional thoughts, I'd like to hear them.

Thanks again.

Blindjim:

That's the first I've heard of the Russound. I'll definitely look into it. As for the Niles, their website says it's rated for 350wpc (see my link). Can you point me to where you read otherwise? Thanks!