Best Used Tube Preamp (under $750)?

I would have to agree with Rgd on the Sonic Frontiers SFL-1 or SFL-1 Signature. After owning one of these gems and putting a good tube in it they are very hard to beat for the money. I have to admit that it had an amazing soundsatge , good depth , and very very nice tonal balance. For the used price in $550.00 to $700.00 range this is, as it was called back in it's day "A Giant Killer". Excellent bass signal and very natural highs when matched to the right amp. You can buy it and re-sell it for the same money if you don't like it. They stay at the same price and are always looked for by others......Good Luck !

Totally auditionable so check it out for yourself. At least as good as any other of these suggestions if not better. Check it out at www.audioelectronicsupply.com for $599 assembled.

Ditto on Conrad Johnson PV-10A. Anthem pretty good also.

I agree with the Conrad-Johnson pv10a excellent preamp I preffer the pv11 though if you can get a good deal on one. What kind of amp and speakers are you using this also plays an important role in system matching

The Quicksilver line stage tube preamp is very nice. I believe there is one listed by a dealer for $449 here on Audiogon. I have owned my Quicksilver preamp for almost 2 yrs. When I bought it is was the older 12au7a version. I just sent it in and had it updated to the 12ax7 tubes and it sounds even better. Quicksilver is all about customer support. The preamp is a beauty as well. It has a very natural smooth sound, but it doesn't go so far as to sound overly warm or liquid as some other tube gear can. Some of the other preamps listed above are great as well, but for the money it is very hard to beat the Quicksilver. Also if you want phono the older preamp from Quicksilver has a phono stage. Or you can buy the seperate Quicksilver phono stage preamp. Good Luck!!