Weird volume issue w/ Pandora's Box

[DGWVI]

So, I've been playing with This today, and noticed that if I have the volume pot on the Expandora over 2 o'clock, it cuts out. It works fine up to that point, and then just kills the volume.
No pics right now, as I need to unbox it, just wondering what I should look for.
The only mod to that section is reducing R19 from 1m to 470k
All the other pots work perfectly, it's just the volume pot acting strange.

 

[Chuck D. Bones]

Visual Inspection, Man, Visual Inspection.

 

[DGWVI]

Trust me, I've gone dizzy looking at it
I've replaced the pot, and touched everything up, though the issue persists.

I'll update the thread with pics after work.

 

[Chuck D. Bones]

Based on the symptoms you describe, focus your attention around C13, R19 and IC4 pins 5-7.
Measure the voltage on IC4-7 with LEVEL at 0, noon & dimed.

 

[DGWVI]

Based on the symptoms you describe, focus your attention around C13, R19 and IC4 pins 5-7.
Measure the voltage on IC4-7 with LEVEL at 0, noon & dimed.

Sweet, I'll get those checked when I get a chance and return with the results.

Another note, I did also disconnect the Scoop control, which is wrapped around C13 (22n in mine) and that didn't have any effect on the volume issue

 

[Chuck D. Bones]

Scoop control? I don't see that in the Build Docs. If there are mods, you need to tell us about them.

 

[DGWVI]

Scoop control? I don't see that in the Build Docs. If there are mods, you need to tell us about them.

Yes, there are a few mods. The original build thread is linked in the OP
Here it is again

The scoop control puts 10k on either side of C13, with the other end of each soldered to a 100n, which is soldered to lug 3 of a 10kb pot, with pins 1&2 tied to ground. Like -



The other mods are your Contour and Drive pots, and red LEDs for clipping diodes

 

[Chuck D. Bones]

If you make our job easier, we're more likely to help.
I'm basically lazy and I don't like having to go fishing thru other posts.

Your schematic above is not from the Pandora's Box schematic. Show us the mod on an actual Pandora's schematic.

 

[DGWVI]

Your schematic above is not from the Pandora's Box schematic. Show us the mod on an actual Pandora's schematic.

Aside from component designations, that particular section is identical regardless of what specific project doc it came from

 

[Chuck D. Bones]

Not true.