Cary SLP-05 Tube Rolling

If you have this preamp and haven't tried swapping out some tubes you don't know what you are missing. I tried all the 6SN7s and found a couple that were very good and they were the metal base Sylvania & the Russian 6N8S 1578 metal based tubes labeled OTK.I recently sold 60+ various 6SN7 tubes that I had tried. I found that the 6F8G tubes were better.To put it simply there was more of everything: detail, bass, soundstage etc. To use these you need an adapter because they are also powered from the top. These adapters are available on EBAY as well as the tubes. Quality of the adapters is variable as I have more then one DOA. An easy trial would be to purchase a matched pair of tubes and get a couple adapters.To get the biggest bang for your buck place them in the third position from the left as you are looking at the preamp. You will find that compared to the top rated 6SN7 tubes the 6F8G's are relatively inexpensive but in my humble opinion sound better.
"Third position from the left", I believe is tubes 3 and 6. Those are the balanced input buffer tubes. Are you running in balanced and single-ended mode? If I remember correctly, the common recommendation is that if you are running single ended, that 3 and 6 are not important and I have read people saying you can even remove them, although I have not tried that. Can you elaborate on your recommendation for upgrading 3 and 6? Thanks.
I am using a pair of of the Cary Audio 211AE's & before that I had a Cary 120 and the Krells. I thought both the Cary's sounded better then the Krells.
DTC: I am running balanced & yes the 3&6 are the inputs. I do not know if you can remove these if running single ended. I purchased the preamp here on Agon from an individual I believe was an electrical engineer & he said the 3 & 6 slots were the most important & that is where I put the rarest or best tubes.
Understood. Most people seem to recommend changing the other 4 tubes and obviously if you are using single ended, like I am, that is the only choice. With all those tubes, did you try rolling the other 4 also?
Which brand 6F8G was the, "best"(in your opinion)? The choices(and flavors) are as varied as the 6SN7s.
Rodman: I was afraid somebody would ask that question and that is why I didn't post this until I got a decent reserve.I liked the Ken Rads followed by the National Union and then the Tung Sol roundplates.The Ken Rads were the best all around in my system with just a little more detail and a great soundstage .The National Union's had a little more bass. I found all the brands perform very well however and given their age are surprisingly reliable. If anybody tries the 6F8G's I would like to hear their impressions.
The 6F8Gs are a great value since they are an equal to 6SN7s and still much cheaper. I have been using a pair of TS with oval mica and really like them.

I recently purchased a pair of Ken Rads which I haven't tried yet.

BTW, if anyone needs adapters I know someone who makes very nice ones for $40-$50 per pair.