Vacuum tube preamp?


I have read that tube preamps can add some "warmth" and perhaps "soften" the audio signal input to the power amp. This has been recommended for systems which seem a bit "bright" in the reproduction of the higher range. I have Thiel CS 2's driven by a Hafler 9180 power amp and a Rotel 971 preamp. I haven't noticed feeling fatigued listening over long periods nor do I hear grain in the highs. I also wonder about characteristics of a given recording as the culprit more than my equipment. Any thoughts? If I did replace my preamp with a tube model I would want one at $500 or less? Do they exist at this low price?
nordic587
Agree with the above. Tube preamps (and amps) cover the gamut from transparent to extremely colored with all shades in between. Better to try out a few and figure out what sound you prefer. Otherwise you will just get a bunch of recommendations that might not fit what you are going for.
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IMHO, the Thiel CS 2's are best driven with a warm ss amp. With that said, as suitably compatible tube pre is a very good idea. With your budget I would consider a used conrad-johnson PV 10 BL. Which BTW would work very nicely with a used conrad-johnson MF series solid state amp and your Thiel CS 2's.