Classic preamp for Plinius SA-102: need advise

I have the newest (and the best, for me) Plinius power amp. The SA-102. It is an expensive amp so my budjet for a preamp is therefore small (1000-2000 US$). BUT, reading some commnents on old classic preamps I found out that I may
get a used preamp which is as good or even better than the ones that are manufactured today.

Could you please give me a hand on this? Here it goes:

1. I do not have a turntable (so phono is not an issue).
2. The Plinius has lots of punch, impact and an extremely open sound. So I am looking for a tube preamp with a liquid (but not too much coloured, of course), soft highs and good bass, plus with LOTS of air.

I thought that maybe an older Audio Research (the SP-10 seems to be bad for CD; maybe the LS-5?) or a nice Jadis might be good mates for my Plinius. What would you advise me (brand and models)?

Tejo