Cary Audio SLP 05 PreampWhat tubes are you using?

Interesting that you're mating this with a Pass Labs amp. Stereophile's
measurements section in their review of the SLP-05 suggests that a match with
an amp with relatively low input impedance, like the Pass Labs, might not be
ideal due to the Cary's high output impedance at certain frequencies.

What's your take on the match? How's the tonal balance of your system?

Regarding tubes, Kevin Deal of Upscale Audio is a dealer for Cary, and he has
substantial experience with 6SN7 tubes. He'd likely have some specific
suggestions (of course with an emphasis on those he has to sell).

I'm currently using the Pope Hollands. I've tried a bunch of them though. It's all a matter of what is most important to you. The rectifier that you've chosen is the best one IMO.

Good Luck with it.

I don't own an SLP-05 but would love to.
I understand that the N7s on the extreme right when facing the pre are for the headphone amp. I would roll tubes to my hearts content. I have tons of N7s and use good "cans". I might use that section to characterize some of the tubes I had. (If I tried that it would be a quite a long while)
If you don't have headphones or even care about that circuit then use "place holder" 6SN7s, perhaps the stock tubes, which are likely the Sino brand and aren't very good. Or if possible leave them out altogether.
The NOS/OS tubes you have are highly desirable. As such I might move the pairs around to find the best order for them. I would inlude the Ken Rad in a gain stage, if quiet enough ,for added bass energy or in a driver stage. If you are afraid of that, then call Dennis Had, to ask what he would do.
If you know what each pair is good at, knowing the sonics of the tubes you have, then you can make, at least, semi-intelligent choices.
Good Luck,
Sounds like fun.

In general is it ok to have many different combos in place at the same time.
They would all be 6sn7 or 231 ?
__________________________________________________________

Thanks for the responses so far.

Tvad, the tonal quality seems to be ok , but each tube seems to change something a little bit. What should be the weaknest with the Cary/Pass Combo ?
My complaint so far is that I can only use about the first third of the Cary's Volumne control.

Jtwrace, I have heard about the Pope tubes but it seems they are only available thru Upscale Audio and he will only sell to his clinets of his equipment. But, I am curious, how does the Pope compare to the other tubes ?

Mechans, I have also ordered a pair of Tung Sol Round Plates to try with the Cary.

The Stereophile test measurements suggest that there might be rolloff in the treble and bass extremes, although Atkinson states the preamp is happier with low input
impedances than with very high input impedances (as found in BAT amps), so
maybe the rolloff isn't noticeable in balanced mode with the Pass Labs ~20K
input impedance.