Many questions about HT pass-through options


I'm trying to consolidate/simplify equipment in my dual purpose (2 channel and home theater) media room. The net is I want to use the same amplifiers and front speakers for both systems without recabling each time I switch.

I'm completely satisfied with my preamp (Musical Fidelity Nu-Vista) and prefer not to swap it out, but want to easily switch 5.1 (via my pre-pro) to 2 channel and back.

I'm considering a new preamp with home theater passthru, or equivalent alternatives not requiring a new pre.

My questions:

1) Exactly how is HT passthrough implemented in audiophile preamps? Is it simply a high quality switch, or is there something more to it?
2) I read in one post that the standard tape loop can be used for bypass. Is this true? Has anyone done it? Isn't there a risk to the internal circuitry of my preamp?
3) In lieu of a new preamp, is there high quality selector switch that doesn't cost a small fortune? Has anyone made one DIY, and if so, can you recommend good switch parts?

Finally - any recommndations for a good quality preamp, preferably Tube, with a really good phone section, passtrhu, and remote controllable. Budget is in the $1500 range used.

any and all advice or opinion is welcome, and appreciated
bdgregory
A BAT VK3i (and I assume other BAT pre-amps) have a volume setting called Unity Gain, which is essentially a HT throughput. The volume control is effectively removed from the circuit.

As a two channel audio only pre-amp, the BAT line is excellent and the VK-3i can be had at truly bargain prices on a'gon.
I had my "stereo guy" tackle this issue for me a few years ago. I have a switchbox that I click in when I want 5.1 and I click out for two channel. I just added a Audio Research SP16 pre that has a processor mode and a nice phono stage. My dealer gave me a great deal in February by selling it to me for $2000 new. I think it lists for $2500 and the price may have gone up. You might be able to find one used at a fair price.
I agree with Dave's method on a standard preamp, with no "bypass"/"direct" input. The auxilary or whatever works fine.
Degrade sound? Not usually a problem really. Just because there's two volume controls in line, doesn't mean degradation IME. Infact, if you're 2 channel pre's sound was pure from that input to begin with, you should have no problem with the same kind of pure sound you'd otherwise get just using the AV pre'pro for the L/R!
Yep, 12 oclock, or you can tinker.
I've, yes also, used this setup many times, and it works great.
I just happened to see this thread after posting on your other one. I didn't realize you had the MF pre so some of my comments regarding the virtues of a 2 ch. pre vs. a pre/pro are irrelevant. I just picked up an ARC SP16 which has the HT pass through. I can’t comment on the phono section, I don’t do vinyl, but the pass through definitely improves the surround sound listening experience over using a pre without the pass through, setting the volume at 12 o’clock, etc. I still say that for music though you’ll eventually come back to 2 channel so it may be an exercise in futility.
Assuming you integrate a pre-amp with a pass through function, does the pre-amp in the pass through mode pass on any of the sonic benefits associated with it when you are listening to it in the 2 channel configuration. Is there a sonic benefit to going through the pre-amp pass through as opposed to taking the surround sound processor straight to the amplifier? Having a pre-amp incorporated into the system certainly is a benefit for CD listening, but I'd like to hear perspectives if the pre-amp pass through also provides any benefit to HT listening, specifically HT concert DVD's.