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
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.
Nordic,

I'm not familiar with your Rotel pre, but I had a Rotel RC1070 pre and while cheap, I wasn't hearing enough differences with other pres that would make me want to change, until I got a Lamm LL2. Certainly I can hear that difference, but the Lamm is like 10x the price of the Rotel. Point is don't assume more expensive will always sound better.
Hi all ! I have had 2 pairs of the CS2's . They are the easiest of all Thiel speakers to drive , so dont limit your choices on the preamp side . A Belles a150 will drive the crap out of those and can be had for $400 - $500...this amp is nice and warm sounding . Dont know much about preamps ,I have used the placette passive and a cary slp-03 for years and both were are excellent. PS... also a nice 40 - 60 watt tube amp would be a good match too.