Understanding Crybaby Parts

[12StringStratMaker]

Hi everyone,
I have a modified GCB95 crybaby that I'm trying to understand.  I was comparing the schematic to the Vox V847 and found the typical talked about components that affect the wah vs woh and etc.  RG Keen's article is great for explaining things, but one of the things I can't find information is the cluster around the zener diode (1k, 0.1uf, 220uf, and ZL9M3) that the Crybaby has and the Vox lacks. 
I was wondering what this actually does?

The schematic I'm refering to is found here:
http://www.freeinfosociety.com/electronics/schemview.php?id=351

Also, the modified one I have looks to have all the standard mods (true bypass, Q, sweep switch, etc), but it also has two extra 1 Meg resistors (one going from just after the 68k (well 53k in mine) input resistor and goes to ground, and one from where the blue wire on the schematic connects to the pot and goes to ground). 
Are these to eliminate popping or something?  Or are they affecting tone?

Thanks for any help.

[jaysg]

one of the things I can't find information is the cluster around the zener diode (1k, 0.1uf, 220uf, and ZL9M3) that the Crybaby has and the Vox lacks.  I was wondering what this actually does?  (big clip) it also has two extra 1 Meg resistors (one going from just after the 68k (well 53k in mine) input resistor and goes to ground, and one from where the blue wire on the schematic connects to the pot and goes to ground). 
Are these to eliminate popping or something?  Or are they affecting tone?

The cluster is more or less a voltage regulator.  You could see it as filtering noise from an external power supply which isn't shown, or as over-voltage protection, or as reverse-battery connection protection, which probably isn't needed.   From my own experience, a generic wall-wart into an early 70's Vox Wah is too noisy to use.  The 1M resistors allow the input and outputs to drain to zero when bypassed.  They should help with popping, as you thought.

[12StringStratMaker]

They should help with popping, as you thought.

Thanks a lot. Glad to know I'm starting to understand.