Can I hook up two amps to the same speaker?

You should be a bit intimidated. If you do this wrong, you risk serious damage to your amps. In addition, to what was said above, I've heard that some tube amps do not like having no load on the outputs while the amp is on. That would be a problem if you switched over to the transistor amp while the tube amp was still on. Yes, you might be able to find a shop to make up a switchbox with what you need. Or, you might consider putting dual banana recepticles on the end of the speaker wires and bananas on the end of the amp wires, put the ends in a handy place and hook them up like an old-time telephone switchboard operator. If you describe why you want to do this, there might be other and better solutions.

The reason why really doesn't really matter, but there is a major factor which nixes this idea. The bottom line is that the swithch box, no matter how you look at it, is a pothole on a perfect highway. I believe regarless of the connections and workmanship there will be inherent factors that have a slight, but, deleterious effect of the signal. Total isolation is impossibe. I'm going to let this idea go. The reason btw, was since I have an SET amp, and my speakers, though 101db, can handle up to 500 watts per. I just wanted the ability, on the rare ocassion I want my ears to bleed..lol...to pump in 100 or 200 watts. I have heard what these babies can do with a 100 watts per and would like to have that capability. Look, I can always have the speaker spades right next to the speakers and unhook and rehook. A bit of a pain in the ass. something I know I would not be into. My fellow audiophools, thanks for your tips. peace, warren

Interesting thread. I actually do this with my set up, without a switch box. So far, no problems noted. I've got the Gallo sub amp hooked up to the secondary voice coil input speaker terminals, and my tube amps connected to the primary voice coil inputs. If I'm going to leave the system on all day and not be in the room critically listening, yada, yada, I'll sometimes save tube life and swap the sub amp leads into the primary voice coil input on the speakers, switch the low pass filter off on the amp, and turn the tube amps off. I terminated the speaker cables form the sub amp in banana plugs for ease of operation when doing this. Is it a general consensus of opinion that I may be damaging my very expensive Bruce Moore tubed power amps by doing this? I always have them OFF when running things this way.
Thanks in advance for the replies,
David

In case anyone else stumbles across this thread, as I did, I just talked to a friend who's a former Bruce Moore engineer, and he confirmed, even with the tube amps off, the transformers will send a high AC signal to the plate and screen grids on the tubes. The tubes are designed for that, but not with the power off.
So, I'll end this practice.

Rolloff, glad to hear that my orignal thread may have saved you from disaster. Seems like it has...peace, warren :)