I just finished my kit and it sounds great, but there is a 10Hz or so clicking noise that you can hear when nothing is playing. There is also some random scratchy noises that I'm guessing from other posts is normal when breaking in new tubes?
Voltages are (Right/Left): IA 222.4/221.9, OA 165.2/170.5, breg 100/97.5, Kreg 1.24/1.07, OB 98.5/96, ba 0/0
I can see the heaters working on the 12BH7 and the 6922. I can't see anything on the EF86s, and they don't get appreciably warm compared to the other tubes, but I read that the heaters aren't normally visible on these tubes and with the sound working well, I assumed they were functioning?
The only other thing that was a bit off was on resistance checks. The manual says A4 and B4 will fluctuate in 10s or hundreds of Kohms and that C4 will be at infinity. For me, A4, B4, and C4 all read out at .619K. There was a past post that suggested this was okay.
http://bottlehead.com/smf/index.php?topic=3379.0Resistance at A6, B6, C1, C2, C6, and C7 all ran a bit high (around 20%).
There is one part that I worried about overheating during soldering, which was the 1uF cap between C4 and C5. Wondering if that might be the culprit. I re-wet it, but wasn't keen on tearing that tough connection apart until I asked first.
There is one other post where someone seems to have had the same problem (called it "motorboating", a term I couldn't quite bring myself to reuse, lol).
http://bottlehead.com/smf/index.php?topic=2413.0 It wasn't clear to me what ended up being the fix, but I checked the problems identified at the end of the post (resistors on 12BH7 and RCA input connections). Didn't find problems with any of that, so I figured I'd ask here.
Thanks!
Robert Perkins
