Ryan H
Ex Member
|
Dan, Super explanation! Thank you. I've isolated the 'crackle' to my pre-amp. Though it's sporting brand new 12AX7s, it appears one of those has an issue.
Anyway, back to the ZKIT-1. As you suggested, I checked the SV-83s for continuity of the heater elements and they 'beep' through just fine. I measured the resistance between pins 4 and 5. One measures 4 ohms. The other measures 3.9. The former is the one that didn't achieve blue-glow status. I rather doubt 0.1 ohm difference matters in that regard. Out of curiosity, I measured the resistance between pins 4-5 on my JJ el84s: 1.4 and 1.3 ohms respectively. Similarly, I pulled out a pair of NOS 6P15Ps: 3.9 and 4.0 ohms, consistent with the SV-83s. It's clear as mud. Apparently the dc resistance of the heater filament, while different between el84 and 6p15P (sv-83) is not the factor that is causing the New SV-83s not to work.
So do you have any other ideas as to why the brand new SV-83s don't appear to work? Firstly, there was no sound whatsoever with the SV-83s in place. And, in particular, why one would appear to work (if the blue glow is any indication) and the other would not?
One other clue, I was inspecting the SV-83s while in the amp (and it wasn't working) and I did spot some intermittent arcing between tube elements. It was at this point that I shut 'er down.
Again, I appreciate your previous response and help. The amp is working fine at this very moment with NOS 6P15P-EV, CCE mod, and 8-2 pins jumpered.
Cheers, Ryan
|