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Not if you use the A10k volume pot like the bill of materials states.

You do only if you want to use an A25k pot like the mod states.

Thread necro...  sorry about that, but I've not really dug around this board much in the past.  The 25ka/18k resistor volume change is not about making a 25k pot  a 10k value.  The resistor is wired from input to wiper, and not in parallel with the whole pot.  This was just to come up with a tweaked taper that would put the voltage divider at -12dB at 50% rotation for unity gain at that setting.  Both the 25ka and 10ka pots put unity at about 2 o'clock with all the boosting bunched up from 2 to 5 o'clock.  Linear taper pots had it around 9 o'clock which was a horribly jumpy taper.  This is based around a +12dB zero gain setting, so once the gain is turned up it gets thrown out the window and really doesn't matter. 

I thought it could have some variance, but that is quite noticeable far as the tone stack goes imo. Never thought he would vary that much from one gen to the other, thanks for sharing.

The brown cap is a 47pf to ground on the input.  That was put in due to some guys getting radio.  Small enough to not really effect the audible high end, but large enough to cut down on radio noise.  The input cap was changed from 47nf to 39nf. That changes the low end roll off from -3db@6.3hz to -3dB@8hz which really is no change.  That was done years ago when there was a shortage of 47nf for a few weeks from all my vendors.  Since it made no difference in performance I just stuck with the 39nf which I used in another spot.   The output stage had it's values changed from the stock 2x 3k3 w/4n7f setup to 2x 10k w/2n2f.  This was done to get a little less loading on the 2nd stage to help the headroom a tiny bit with a weak battery.  The 1k5 preset resistor in the treble control was changed to 1k to bring the brightest setting back to where it was with the 3k3 setup.  You would have to squint your ears to really notice any of these changes.  What can't be seen is the treble control was changed to linear to cut back on the dead spot between 7-10 with the audio taper.  That one had a big effect on knob settings.  I'm not sure, but it probably has the volume pot tweak which had the resistor soldered on the pot, and then it was added later to the board which came after the version shown.  I never promoted those pot changes because they don't effect the sound - just smoother knob settings and I didn't want it to look like I was trying to resell a new version to people.