Bottlehead Forum
Bottlehead Kits => Mainline => Topic started by: bmnathe on January 26, 2018, 01:57:41 AM
-
Hey guys - I bought my kit assembled from the first owner. It worked great for a couple of months until recently - it started producing heavy distortion at any volume level; seems to be mainly from the lower frequencies. I don't have much issue until a track with bass is played.
When I first received the kit, I noticed that two wires were misplaced (reversed) on the balanced jack. I fixed that and no issues. Since the distortion started, I re-soldered nearly every joint and biased the tubes a few times (not much drift). Besides verifying correct wiring, soldering, etc. on the actual amp - I have tried different sources, power plug, power supply, wiring.
The tubes glow like normal. I noticed that one power tube is a bit microphonic when I touch it. This tube seems to produce the most distortion (checked by swapping channels) although both channels are distorted.
Anything else I should check before I buy new tubes?
thanks,
B
-
Have you checked all the voltages?
-
Have you checked all the voltages?
Yes - I check all voltages and resistances - everything checks out. There's no obvious signs of capacitor damage - no leaking or bulging. All ground wires and nodes are grounded.
-
Have you changed anything upstream or downstream of the amp, like headphones or source?
-
Have you changed anything upstream or downstream of the amp, like headphones or source?
No - all sources, cables, power source, etc. is the same as when the mainline was working well.
-
My best guess is that you have a flaky solder joint that's common to both channels. I've had issues like this pop up on Cracks when there's a bad solder joint somewhere on the shared ground buss.
-
My best guess is that you have a flaky solder joint that's common to both channels. I've had issues like this pop up on Cracks when there's a bad solder joint somewhere on the shared ground buss.
thanks - I'll double check it but I re-soldered everything already..
-
Guys - I did nothing else and the issue has 'magically' resolved itself. Not sure what the issue ever was.....I didn't even touch the unit. I don't think it's a power supply issue because I run through a voltage regulator. I am still going to install new tubes because one power tube is a bit microphonic....
thanks!
B