Re: High end preamp with passthrough
My solution to a need for a multichannel preamp was the Meitner Switchman 2 preamp/switcher which can handle four (4) multichannel (6 channel) sources. I still use an older preamp/processor for DD/DTS decoding and run it's analog outputs through the Meitner. I also run a Blu-ray player's multichannel analog outputs and a Universal player's analog outputs through the Meitner.
The Meitner preamp stage blew away my pre/pro's preamp stage. So did a McCormack MAP-1. Pre/pros are "crippled" by the need to process digital sources so even with today's technology, I'm not sure there is a Pre/pro with a better (analog) preamp stage than the Meitner.
Last time I checked, the Switchman-2 had been replaced with a far more expensive Switchman-3 tailored for the audiophile world (rather than for the recording studios).
Nowadays, I opt to use a 2-channel tubed preamp for 2-channel music listening. I even swap the cable connections instead of using one or the other preamps in bypass mode (I also think cables make a difference and I didn't want to spring for extra expensive cables).