Incorrect voltages after installing Speedball [resolved]

[Adelz]

After installing my Speedball upgrade, some of the voltages are way above where they're supposed to be. I've checked for a loose connection but haven't been able to find one. The glow in my tubes appears to be even on both sides and all the LEDs light up; the ones on the main PC board and 9 pin socket are very bright and the ones on the small PC boards light up but are dim in comparison. My voltage measurements are below - highlighted in yellow are the numbers furthest from their intended amounts. When testing audio, the sound from the source is not distorted or muffled. There is buzzing in the left channel; when the volume is completely off, the buzzing goes away, but once it's turned up it becomes immediately audible. What's the best course of action from here?
 

 

[Paul Birkeland]

Please double check the R1 values on each board.

-PB

 

[Adelz]

On the small boards, the voltage of the 31.6K resistors on the R1 positions measures 185. On the large board, both have a voltage of 0.

 

[Paul Birkeland]

Measure the resistance of each actual resistor.  I think you have a pair of them swapped.

 

[Adelz]

Thanks very much for the help! I did have two of the resistors swapped. All the numbers are perfect now. 
 
When I power it on, though, there's still a very loud buzzing in the background. As all the voltage measurements are within range now I'm really not sure what's going on.
 
Edit: I'm still experiencing this fairly loud buzzing in both channels; when the volume is turned all the way down, it's very soft, and when turned up the buzzing gets louder. All the LEDs glow and are in the correct position. The 2N222A transistors are both on the small boards and the 2N2907As are on the large board. The 237 ohm resistors are on the small boards and the 31.6 ohm resistors are on the large board. There are no solder bridges between the TIP-50 or MJE-350 transistors.
 
I've swapped out the tubes and the problem remains the same. All of the voltages are normal (A1 and A6 on the 9 pin socket read 76 instead of 90, but I assume that's close enough). Before installing the Speedball upgrade, the amp functioned perfectly. What should be my next step for troubleshooting this problem?

 

[Paul Birkeland]

I would be looking for loose filter capacitors that may have been knocked loose during the modifications.
-PB

 

[Adelz]

I checked and resoldered all three filter capacitors and the problem is unchanged. Oddly enough I think one may have been a little loose, but the buzzing is still as loud as ever.

 

[Paul Birkeland]

A loose black ground wire can also cause this issue, though it seems less likely.

 

[Adelz]

Which wires specifically should I be sure to check?

 

[Paul Birkeland]

Which wires specifically should I be sure to check?

All of them (there aren't that many)

 

[Adelz]

All of the ground wires are secure and all the grounds listed in the stickied thread measure zero. 
 
I think I've found the problem. It seems the rocker switch is malfunctioning. I turned it on regularly but when I went to turn it off, even in the off position the amp was still powered on. I'm assuming I need a replacement. 

 

[Paul Birkeland]

After rereading your post, do you get buzzing with a source connected?

 

[Adelz]

Yeah, I do.

 

[Paul Birkeland]

I'd go ahead and just reheat all your solder joints.  This is the most often cause of the symptoms you describe.

-PB

 

[Adelz]

Okay. Do you think it could be the switch, though? 
 
Also, I have a ground wire between Terminal 4 and 14U instead of 22L. That's still fine, correct?

 

[Paul Birkeland]

Okay. Do you think it could be the switch, though? 

The power switch?  No. 

Also, I have a ground wire between Terminal 4 and 14U instead of 22L. That's still fine, correct?

No problem there.

 

[Adelz]

Oh, it isn't? The revision in the Crack manual says it's fine and nowhere does it mention that the revision will not work with the Speedball. 
 
Anyway, I switched that ground wire from 14U to 22L. That didn't fix the problem. I really don't know what to do next.

 

[Paul Birkeland]

Sorry, I mistyped there.

I have repaired several Cracks recently that had the symptom you are describing.  All of them had cold or loose solder joints that needed to be reheated to function quietly.

-PB

 

[Adelz]

Ah, okay. Do you think any resoldering of the PCBs will be necessary or does the buzzing mean that it is most likely a transformer/capacitor issue?

 

[Paul Birkeland]

Ah, okay. Do you think any resoldering of the PCBs will be necessary or does the buzzing mean that it is most likely a transformer/capacitor issue?

Solder joints on PC boards are generally much easier to inspect (there is a lot of online information about soldering PCB's), but it won't hurt to reheat them also.

-PB