Tube cdp with ss units...

There are a lot of tube cd players out there and one of them might be enough to warm up your system but you'd probably get more warmth out of a tube preamp or amp. I have a Primaluna integrated and it has a nice warm sound.

When I added a Jolida 100a w/ the stock tubes to my ss system (restored Kenwood 700m and 700c, VS vr4 iii hse) the difference was detectable but quite small. Warmth? I'm not sure. When I began rolling tubes, some made the system sound even brighter and "cooler" than a the original ss cdp I started with. But others, especially the famed GE triple mica black plates and the Sylvania Gold brand gold pin 5751s, gave me liquid mid-range and highs that the ss player lacked. The advantage of the tubed cdp, for me, is the range of coloration --some cooler, some warmer--that can be achieved with different tubes.

I have a rare, or hard-to-find, Cary CAD-855 based on the Rotel RCD-855. It is the best player I've had to date, beating out budget DACs. It is warmer and takes off the CD edge sound, but changing 12BH7 tubes and cables helps too. Some CDP I've owned were warm but not that musical to my ears (Roksan/NAD). One thing, I may be biased, but I feel my full tube setup give a more enjoyable sound, though comparable SS equipment in general can reveal more detail. As for mid-bass, my tube CDP has warmer, smoother and fuller vocals, but I cannot say it has a warmer midbass. I would change output tubes for a 'fatter' midbass such as my JJ KT88.

Try a Sonic Frontier tube dac. I have the SFD MkII, with the right tubes, you can be in heaven. I replace my ARC CD2 with the SFD MkII and never looked back.

I’d argue that your source should provide an accurate and reliable representation of the information on the disc -- at least that's my opinion. Some tube CD players, such as the Jolida JD100, use solid state op-amps for the analog output sections, then they add a couple of tubes as a "buffer" stage, in effect using tubes as a tone control.

That said, CD players do sound different (duh!), and some are warmer than others. On the warm and musical side are the new Naim CD5i-2 (the new version, not the original CD5i, which is sharper and brighter), the Rega Apollo or Saturn, and, less expensively, various Arcam models such as the CD73T (full disclosure—I have an Arcam for sale on Audiogon).