2. tech-talk
  3. 1325852152

VAC 30/30 & Sophia 6SN7's

I recently purchased a VAC Ren 30/30 amp that is an incredable little amp and the best so far in my system. I decided to try some tube rolling in the front 4, 6SN7's and purchased a matched pair of the highly reguarded, Sophia 6SN7's to try out. When I install them in the inside (splitter positions) and then power up, a very loud hum is generated to the extent that I am afraid I will damage something so I shut it down. If I install them in the outside (driver) positions everything is fine and the sound is great. My question is: Has anyone experienced this? Are my tubes bad?
I do have an email in to VAC but thought I'd seek out any experiences that other, more knowledgeable audiophiles might have.
Thanks
Markus
markus1299

Showing 4 responses by markus1299

markus1299 OP
252 posts
 
Thanks Almarg for the info. I will pass your suspicions on to Kevin for consideration. I believe, for what we paid for these tubes, we should not be seeing this trouble But, it's all a learning process in this hobby isn't it?

Markus
markus1299 OP
252 posts
 
Prior to insalling the Sophia's, I was running Sylvania 6SN7GTB's in outer sockets and RCA VT231's in the inner sockets. I did notice on the Sophia site that there 6SN7 spec's were the same as the GTB's so I thought I'd give them a try. They are amazing in the outer sockets and really take the sound up a notch or 2 but will not work in the inner sockets. Surprised! Guess I need to get the tube tester out per Al's suggestion about leakage. I did get the 1 year warranty so we will just have to see how this goes down. Thanks guys for your input.

Markus
markus1299 OP
252 posts
 
Update- Kevin Hayes of VAC emailed me about my experience with the Sophia's and would like me to send him the tubes so that he can test them and sort out the problem I am seeing. How many manufacturer's are willing to do that for you? Anyway, I'll probably take them over to him (I don't live to far away) and I'll let everyone know what his results are. Should be interesting.

Thanks

Markus
markus1299 OP
252 posts
 
Raquel,

The Sophias are not standard spec 6SN7's. Their data sheet reflects that they are higher voltage equal to GTA or GTB prefixes.
More to discover