How hard is this on a tube pre amp?

It seems to me that you have a lack of input level and using player with weak signal.
There are players that have 2v output and perhaps you should look for the one instead of what you have.
Your volume settings past 12:00 should realy shake the house while moderate volumes should between 9:00 -- 10:00 or 10:00 -- 11:00
Your tubes in preamp pretty much 'don't care' about your volume settings. Oppo players have only 1v output.

Czarivey, oppo list the output at 2.1 SE and 4.2 balanced.

Analog Audio Characteristics** Frequency Response: (RCA) 20Hz – 20kHz: ± 0.2dB, 20Hz – 96kHz: -1.5dB. (XLR) 20Hz –
20kHz: ± 0.3dB, 20Hz 96kHz: -1.5dB
Signal-to-Noise Ratio: >130dB (A-weighted, auto-mute), >115dB (A-weighted, no auto-mute)
THD+N: <0.0003% or -110dB (1kHz at 48k/24b, 0dBFS, 20kHz LPF), <0.0017% or -96dB
(1kHz at 44.1k/16b, 0dBFS, 20kHz LPF)
Output Level: 2.1 Vrms (RCA) or 4.2 Vrms (XLR) at 0dBFS
Dynamic Range: >110dBV
Channel Separation: >110dB

And speakers are martin logan ascents. Not the most efficient speaker around, but not terrible.

It's a live show from PBS... The levels are just crazy low. The funny part is the interviews shown between the live set are Normal, which is loud as heck at the volume needed for the music.