Best Tube PreAmp - McIntosh vs. Audio Research vs. VAC vs. Atma-Sphere

I have some relevant experience with some the pre's and your amp.  I ran the Luxman M900u for a couple of years - - very nice amp, but I definitely thought it benefited from partnering with a tube preamp; otherwise it was a little too "gossamer" for my system and tastes.  When I bought the amp, I was using the PS Audio BHK preamp, but I bought the amp with the C900u.  The C900u clearly showed me that there was a good bit more to be had than the BHK was giving me in terms of musical information.  I sold the BHK and haven't look back on that.  But over the longer haul the C900u with the M900u just didn't light my fire, sounding a bit thin and "see through" (I run TAD CR-1 speakers, which do need some warming to shine right).  Then I tried an ARC Ref 40 and I found this to be a synergistic combo, bringing a "fleshier" sense to the music.  Just my experience, and YMMV.

I never thought about burning through tubes & how expensive it could be while video watching.

The Luxman m900u has a very useful feature: two set of input.

Connect one input to HT and the other to stereo preamp, no need to turn on the preamp while using HT, and not even need the HT Bypass function in the preamp!

c-j

Your front l&r will be a 2 channel ’front stereo system’ via an integrated amp or preamp/amp pair. Used by itself for music, OR, used BY the AVR for video.

that preamp will need HT Bypass INPUT, that is how the AVR controls the front volume along with all the other channels it amplifies.

AVR will need FRONT L&R Preouts.

Consider low bass now: from the main speakers always, or if sub(s) will be used: how you get/control/ and if always available i.e. volume controlled via AVR and for just music, how use sub(s).

I would not complicate that with tubes myself, however, you know how much heat your cabinet/area/room can handle.

I think the prospect of not burning through tubes while watching TV/movies outweighs whatever you might lose in sound quality for watching video.  But, that’s me. 

I get that, but you can get thousands of hours out of the tubes. If you spend the same time listening to music the life is the same.

Stereophile did a survey at one of their shows in the early 2000s. It was two identical home theatre setups. One had the normal box store amplification and speakers, the other had high end stuff. People were not told what was different and were asked to gauge their experience. The room with the better equipment got better marks for picture quality! But the only difference was the sound.