Tube preamp for SS amp

Just to clarify, the input impedance of the amp should be at least 10x the output impedance of the preamp.

Tube preamps can have fairly high output impedances, e.g. 1.5 kohms. 10x this output impedance would require an input impedance of at least 15 kohms for your amp. That's a pretty low input impedance for an amp, but they are out there, Pass Labs for example.

Many SS amps have an input impedance of 47 kohms or higher and you should have no problem pairing a tube preamp with one of these amps.

Try to find a review with measurements of the tube preamp you are interested in because manufacturers give a nominal output impedance with their specs. The preamp may hit a significantly higher output impedance at certain frequencies.

This question comes up often and there are a number of threads on this subject you can browse for that will give you recommendations for specific combinations.

Thanks for all the feedback. Based on all the research I've done I'm leaning towards 6SN7 or the 6922. I have had my eye on the cj et3se however I'm not sold on the volume control that it uses (push button/remote) and I'm not sure the entry level classic 2se (both use a single 6922) is enough of a preamp (ie performance not features). Herron audio has a 6922 based pre that I may investigate. There is a used VTSP-1a/166 here on audiogon and a NOS VTSP-2.

"12-25-13: Chad2635
Thanks for all the feedback. Based on all the research I've done I'm leaning towards 6SN7 or the 6922. I have had my eye on the cj et3se however I'm not sold on the volume control that it uses (push button/remote) and I'm not sure the entry level classic 2se (both use a single 6922) is enough of a preamp (ie performance not features). Herron audio has a 6922 based pre that I may investigate. There is a used VTSP-1a/166 here on audiogon and a NOS VTSP-2."

That's not a good way to go about this. You can have 2 preamps that use the exact same tubes and they will both sound very different. In a case like this, demo's aren't optional. You have to do it. If your only demo option is ARC, I recommend you try to put something together with them, as opposed to just guessing. When you buy equipment without listening to it first, be prepared to fail. (Understand that I'm not trying to be negative or mean. I'm just very direct in how I communicate.)

You're probably right. It's tough being an audio enthusiast and reading about new makes and models with everybody trying to outdo everybody else but in reality who actually has access to audition even a fraction of what's out there. Even the hifi shops can't afford to stock all models....I know because I've called and more times than not if they don't have what you want they make you special order it and will only exchange it. I guess what I need to do is pick a shop that carries at least 2 brands I'm interested in to better my chances of finding a match.

Chad, I am no techie, but I think CJ make quite a big deal of their volume attenuator, indicating they use a discrete resistor for each volume increment to attenuate the volume (in 0.7db increments all the way through)...somehow preserving the integrity of the signal by having just the one resistor at that increment? AT least that what I could make out of it...sorry for not reading it properly if I got this wrong. Its on their website. Perhaps there are better ways to attenuate, but as people like to say, its often about the implementation than the theory anyway. Hope you get a chance to hear the CJ ET3SE...if it sounds as close the GAT as people say, then it should be quite a special preamp.