Cary Audio SLP 05 PreampWhat tubes are you using?

I recently purchased a used Cary Audio SLP 05 Preamp from a fellow Audiogonmer. It did not come with the original tubes.Instead supplied were some NOS Raytheon 231, and Sylvania 231.

I have also bought a pair of NOS Ken Rad VT-231 tubes, and a few of the Sylvania short bottle.

I have changed the rectifier tube to the Phillps GZ 34 metal base mini watt made in Holland.I have also installed the HiFi fuses.

Any other suggestions as to tubes for this Preamp, there seems to be so many ?
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.
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Congratulations on owning a great preamp. The Sylvania short bottle 6SN7W are great tubes. I would also try the 1578 Russian 6SN7 tubes to add more air and space between amazing sounding tube.

Disclaimer: I do sell tubes on Audiogon.
Yes, the Popes have gooten almost impossible to for sound I still like them better then the RCA/Sylvainia GTB's. I would like to try some Tung Sol RP and some Russian 1578's. The cost has just gotten out of control on these though. I'm so happy with the Popes (and have many of them) that I'm inclined to stick with them unless I find some NOS Russian/RP's on my frequent search.

my amps imput impedance is 100K and the SLP-05 and Clayton match is great IMO.
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