So I built my crack probably a week ago, and it sounds great.
First listening session I noticed a slight hum and some crackling, and switched the tube to the other one I had hanging around, and the crackling is gone, but there is still a slight hum that gets louder when the thing warms up. (think I hit the power button, and the hum fades in)
I have reflowed the solder in every joint twice now, and swapped the Black wire from 4 to 22L to 4 to 14U, no dice. Hum is still there.
I'm at a loss for what this could be.
Here are a ton of pictures:
http://imgur.com/a/P91yEAlso, this happens in both my HD555s and HD650s, using an Audioengine D1 as a DAC.
Edit: I am doing the Grounding run through sticky, and will post readings from that here, and hopefully one of you can tell me where I have it wrong.
This was in M ohms, with the black lead touching the chassis, and the tubes in their sockets, with them out of their sockets, these are both 0.
Also, all unlisted values were 0 M ohms, but many of them started at .04 to .10 and went down to 0 after a few seconds.
RCA Sleeve that your wires go into on bottom -
White - .10
Red - .09
Edit 2:
After resoldering all the grounds and plugging the amp into a grounded outlet, I have a new hum, but this one dependent on volume.
Still, as far as I can tell, only in the left ear.