Question re: output upgrade DC measurements

[Urbansandz]

I just installed the output upgrade (Wow, amazing reduction of noise on my system). At the end of the install voltages were a little off at terminals 45 and 60. I was getting 7.11VDC at 45, and 6.34VDC at 60. Terminal 60 seems close enough to the target of 6.5VDC, but I wasn't sure if I should worry about the 7.11VDC on terminal 45. Is that within spec? The manual only says that it should be approximately 6.5VDC. All the other measurements were perfect.

Thanks for this incredible upgrade. At the highest volume I now get no discernable noise at my listening position, and I wasn't expecting that big of an improvement.

 

[Paul Birkeland]

If the regulated voltages (OA and OB on the C4S board you added) are correct, then I wouldn't worry about the 7.11V.  That may just be indicative of a 6CM7 with unusually high emission.

You could double check this by swapping the 6CM7 tubes from side to side to see if that voltage follows one specific tube. 

 

[Urbansandz]

Thank you. Yes, OA and OB are measuring the same at 182, so all good. I switched the tubes and the difference did carry over, so it seems that it's all due to the difference in the tubes. With the switch, it was less pronounced as the tube that was measuring 7.11 is now at 7.05, and maybe that will lessen even more with continued use.

I think I can call this build complete and successful. Thank you! With a Mainline, Kaiju, BeePree2, and a Moreplay, I'm not sure there's much left for me, but it's been a very fun and addictive journey. I would love to see a tube DAC kit one day.