Any suggestions on Tube Buffers?

This is pretty funny actually. The purpose of a buffer is to compensate for incompatibility in impedances between components, the input impedance of a buffer being very high, and the output impedance being very low. I know that it is obvious, but that is why it is called a "buffer", not a makeyourhifisoundtubeywhatzit. It is a very useful device if the driving source has a higher output impedance such as inexpensive CD or DVD players that use op amp based output stages driving inputs of highish input impedance or long cable runs. Presumably, your preamp and amp are matched, so better sound does not come from adding a set of interconnects and an active device between them, a cheap active device, with a minimal power supply to boot. My best advice is to save for a nice tube preamp. They come up on Audiogon frequently starting around $300.00. If you like it, you will be able to sell your present preamp and recoup a substatial part of your investment and probably end up in a pretty similar place cost wise. And yes, I actually own a tube buffer, but do not use it. Just my two cents.

In the above post, it should say......"driving inputs of lowish input impedance", not highish input impedance. Of course.

Viridian makes an excellent point! that is the primary reason for a 'buffer' - tubed or otherwise. In fact the BBA I alluded to stood for Buffer Booster Amplifier, and was made specifically for impedance compatibility. a common use for this is between a device of high output impedance to one of low input impedance, like a SS amp. You'll need to know specs to determine if this is the case for you.

The sound benefits in theory are fuller sound and non-rolled off extremes (characteristics of impedance mistmatch) but beyond that, there is an alteration in sound from the unit itself, impedance matching notwithstanding.

I must agree with the growing consensus on this thread. I would save for a tube preamp. I owned a Musical Fidelity X10v3 tube buffer, with the external power supply, and although I liked it for a period of time, I ultimately removed it from the system. It never wowed me like many tube preamps have.

I've been searching a little on Agon and found this thread with some people that have real experience with a buffer. It's all pretty positive.

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1202443614&openfrom&1&4#1