Popping and Cracking in Left Channel after Speedball

[ajzamora0]

Hello,
I put together the crack and everything sounded great. Very clean. After the speedball upgrade, there is a popping and cracking coming from the left channel in my headphones that appears as the tubes warm up. It sounds like the noise you get from a dirty vinyl record. Volume know doesn't affect it at all. All my resistance and voltage numbers are good, but the 2 LEDs on the B side of the small board do not light up. I should mention I installed the PN2907a backwards on the B side, performed the checks, then corrected it when I was getting bad voltages. I've tried the chopstick test on all joints and reheated all my sodder points, but nothing changes it. It happens when there is no source connected as well. I'm worried I may have fried the small board from my dumb mistake, and I also can't revert to the base crack because I snipped too much of the resistor leads. Please help! I'll buy another speedball if I have to. Thanks!

[Paul Birkeland]

Can you post your voltages for terminals 1-10?

How long was your Crack running before you put the Speedball in?  Often crackling like this is an issue with the stock build.

[ajzamora0]

I had only run the stock crack for about a day before speedball, may have jumped the gun.

I ended up reverting to stock, replacing the cut resistors with 3.3K ohms rather than 3k and 22k rather than 22.1K (it's what my local store had in stock). Values are still within range, but is there any reason I shouldn't run with these resistors? I fired up the crack and it sounds great again. I did notice the same cracking sound, however, when measuring the voltage on terminal 5. It may have been a bad solder joint there. In any case, I plan to listen to the stock build for a few weeks before giving the speedball another go. Voltages after reverting to stock (with new resistors) are listed below for reference:

1: 80V
2: 174.3V
3: 0V
4: 174.3V
5: 81.2V
6: 0V
7: 110.4V
8: 0V
9: 108.6V
10: 0V

I will update once I go for the speedball again.

[Paul Birkeland]

If you poke at terminal 5 and that makes noises, you have a solder joint in your build that isn't 100%.