Recomended tubes for my Cary Audio?

I have 2 mono Amps Cary audio CAD 40 M Special Edition with 2 Sovtek EL 34G and 1 Sovtek 6SL7GT. Could anyone recommend me some better tubes to optimice the sound?

Kirk at Cary recommends GE or RCA 5691 Red Base NOS tubes as a replacement for 6SL7GT's. Cary sells the 5691's. Check their website at
You should try Svetlana or JJ EL34 tubes. They both will give you a nice improvement in the sound. Which you like depends on your tastes.

The 5691 recommdation seems like good advice. Especially, coming from Cary.

This amp is a little underpowered in my opinion. If you ever come to the same conclusion, you could give JJ KT88 tubes a try. I was once interested in this amp, but found it not up to driving the speakers the seller paired them with during my audition. I called Cary about using the larger tubes, and they let me know I could. From what I remember, the amp may be autobias.
I agree with all of the above, RCA (or any red base) 5691 along with JJ E34L's. If you have 5u4g rectifiers, try GZ37's. These are Carys reccomendations for my SLA 70 sig. Sounds great!