[yeastguy]

I've been enjoying my new Ultravalve the last few days and was wondering if anyone has done any tube rolling. I have a new quad SED EL34's I bought for another amp about a year ago. Prior to the new amp's EH 6CA7 output tubes, I always felt the SED's were the most musical. Also, the rectifier and input stage tubes make a difference?

[trackball02]

Before you start tube rolling, make sure you give enough time for the tubes to break in (about 100 to 200 hours), and see if you are happy with the sound.
I just posted my comments about my experience with the Ultravalve (see the other thread on UltraValve build). I do not have any experience with the SED EL-34s. It would be interesting to hear from you what you think since i'm considering replacing the stock EH tubes with either the SEDs or PSVANEs.

By the way, stay away from the JJ power 6CA7. I had two of them fail within 4 months. Poor quality control. I'm going to throw out the other 2, just not worth it.

[yeastguy]

I don't plan to change anything for at least the thirty day evaluation period. The amp sounds wonderful now...I just wanted to know if anyone had experience with SED's.

By the way, I have had good luck wit JJ EL34's and prefer them over EH/Sovtek as well as all the re-issue names made by EH.