Can 2 preamps go to one amp?

Please excuse what may be a silly question but, while I appreciate sincere sound from my system, I don't understand all the electronics involved -yet (I'm slowly learning a lot from all of you). My question is this. I'm primarily concerned with the quality of my analogue music but I do ocassionally use my system for Home Theater. I don't want to run my TT thru the surround processor because I want it going thru a good quality tube preamp. I don't want to spend an unlimited amount of money on the home theater aspects of the system (but I want it fairly decent)so I'm looking at the Anthem PrePro. I have Ayre V3 amps. Can the Anthem PrePro and the Phono preamp each connect to the Ayre and then connect the Ayre to the speakers? One set of speakers and one set of amps connected to 2 sources. Thanks for any comments.
Personally, I would be more than a little nervous about accidentally overloading the amp.

Have you considered a setup where the signal for front left and right HT goes to its own particular input on the tube preamp? Some preamps even accomodate for this by having a direct passthrough so that you don't run into problems with volume matching. A number of preamps on the market have this kind of circuitry.

Hope this helps.
Since I don't see where you have a regular 2ch pre amp; just a phono pre(with its own volume control?) If this is so, just change the ic's Naturally while the tt and phono stage are powered off.
You can't hook up two preamps to an amp without an A-B switch. The preamp will take the path of least resistance and feedback into the other preamp. You should be able to find a high quality A-B switch, maybe even and automatic one.