Which AV processors have an analog pass-thru?

I added a tubed preamp to my HT system for music and did just what Slartibartfast suggested. My Sony C333 SACD player is connected directly to the tubed preamp. The main L/R channels from the A/V processor, a B&K Components Reference 10, are also connected to the tubed preamp. You can also accomplish this goal by connecting the tape monitor out to the tubed preamp; my understanding is that the signal passes through the A/V preamp virtually untouched.

The Anthem Pre 1L and 2L are both tubed preamps with a processor loop - kinda the opposite of what you asked but they were built with your situation in mind.

I guess my viewpoint is that if you are concerned about audio quality, you shouldn't be wiring your system this way. You should run the 2-channel output of your processor into an input on your preamp or a processor loop if available before running your preamp into an analog pass through input on your processor. This is a bigger pain to deal with because you need to set the position on your volume control for movies but my perspective is that the noticable loss from movies would be much less than from music using an analog passthrough.

The Krell HTS2 has an analog passthrough.

The Bryston SP1 and the Aragon Soundstage both have analog passthroughs.

EAD TheaterMaster 8000 and TheaterMaster 8000 Pro have
analog passthroughs.

The Classe SSP 25 has Analog by pass on it.