Does a tube preamp warm up sound of SS amp?

The Bryston has a lowish input impedance on its XLR inputs, 20K Ohm per phase (it's common to give the sum of the phases in spec sheets), making it a poor match for some tube pre-amps with high output impedances.

The single-ended input of the Bryston is 50K Ohm, which will work with more pre-amps, but I'd still avoid very high source impedances (say 1000 Ohm and above).

If you want more flexibility, I'd look for an amp with a higher input impedance like 100K Ohm.

Thanks for both comments. Very helpful. The Audio Research ls5 mkii has Input impedance of 200K ohms balanced and Output impedance 400 ohms balanced Main (2), 20K ohms minimum load and 2000pF maximum capacitance. From what I think you're saying that ARC could work, right? Laurence

If bryton has low impedances the Manley shrimp is a good preamp for it because it has only 50 ohm output impedance.Good luck

I've used my BAT preamp with the 7BSST amps and had no problems. Bass was strong and deep.