Issues withGreen Russian Muff clone w/"Mids" mod

[slashandburn]

I've been half-heartedly fighting with this one for a few days now. Against better judgement I built it blind as I had an extra enclosure around while I was etching some boxes and thought "why not, can never have too many fuzz pedals". I should've spent more time looking at the layout but I saw verified in the comments and PinkJimi's name in the notes (not that he seemed to be in anyway responsible for the layout) and just jumped in.

I just lazily assumed it was based off the AMZ Presence/Body  http://www.muzique.com/lab/tone3.htm control mods that I played around with years ago and remember sort-of quite liking. On closer inspection that doesn't look to be the case and I can't work out what the hells going on with this tone control.

It works, but it's nowhere near unity except with the tone control full CcW and the "Mids" control fully clockwise.  I've tried to trace the layout to the best of my limited ability to come up with something resembling a partial schematic but it doesn't make any sense to me.   Lugs one and two of the "Mids" pot appears to be tied back to the collector of Q3, and the 62k  resistor in there just to adds to my confusion.

Anyone able to offer any insight before I scrap this build amd just replace it with a regular muff and add in the AMZ body control myself (probably what I should've done in the first place)



Link to page: https://effectslayouts.blogspot.com/2015/01/ehx-big-muff-green-russian.html?m=1

My (probably wrong) interpretation of what I'm seeing happening around the tone circuit of this layout:



Does this tone circuit make sense to anyone?
Apologies in advance. I should know better than to follow Layouts from this site, given there's no schematic to follow.

Edit: I'm halfway Considering putting Mids pot lugs two and three to ground, changing the 47n cap to a 3.3k and then also using the other part values as per the AMZ presence controls (would also require omitting the 62k resistor) which should bring it in line with the AMZ circuit, assuming the rest of the layout is correct (which I'm not totally confident of)

[slashandburn]

So I've tried those changes I mentioned in the edit from on my last post in an attempt to bring it in line with the AMZ presence control and now I have....... exactly the same issue! Ha. So I'm left now assuming that the tone circuit on the layout above probably works in some shape or form and that there's either a different error somewhere on the layout or an issue somewhere else on my board, the latter being the most likely. Probably a wrong component value somewhere that I can't see for looking at - or a dodgy pot - given the nature of the issue.

Moral of the story so far - be wary of using layouts with no corresponding schematic, especially those with mods. And probably stick to the usual troubleshooting steps before jumping to conclusions that someone else's (verified) work is incorrect.

[pokus]

Your drawn schematic looks alright. Also the layout should be correct. All this pot does, is changing the frequency response of the high pass filter by adding another capacitor in parallel. What would cw end up in more mids and also a little more volume.
Like you mentioned, there's likely a different mistake on the board.
You can also just leave the mids pot out and have the original tone stack (although the 68k should be swapped with a 22k too).