A friend of mine got one direct from him in 2013 or so, and it was so shoddy and haphazard looking; like it was thrown together with hot glue.
I guess it's fair to assume that if the manufacturing is iffy, the engineering would be too... where is the pride in making something good?
Might add a pot to control the Q of the filter. Easy enough to do.
I'd breadboard it first. My experience with modding CryBaby wahs is that when raising R9 beyond 100K there is no increase in Q. Might even be less, depending on the inductor. If you're shooting for super high Q (which may or may not be desirable), then you need a high Q inductor which means the winding resistance needs to be low. I have some of these sweet babies and the winding resistance is around 30Ω.
Interesting to hear about the 4049s— do you find them to be noisy only in CMOS distortion stuff, or also when they’re part of PLL/Octave circuits? I think I have two or three old production ones (Fairchild? I don’t remember, but def not TI; something from the 70s or 80s) that I got in a box of old parts years ago. I’ll give ‘em a try.
CMOS gates were never intended to be used in a linear mode. A few clever guys like Craig Anderton, figured out that certain CMOS gates could be operated in linear mode and wrote about it back in the '70s. After reading that stuff, I experimented with running CMOS inverters in linear mode back then. At the time, there were several manufacturers, RCA, Fairchild, National, Signetics... making CD4000 parts. Fast-forward to today and a few big names (TI, ADI, ON semi) have gobbled up the competition. AFAIK, TI is the only producer of CD4000-series ICs. Their CD4069s and CD4049s are noisy when run in linear mode. Oddly enough, their CD4007s are quiet in linear mode. If you're making octave-down circuits or PLL circuits (like the Boss DF-2), then the CMOS ICs are running in digital mode and therefore analog noise is not a concern. I
always socket CMOS parts when running them in linear mode because the datasheet tells us nothing about what to expect in linear mode. The only way to know if a CMOS gate is any good in linear mode is to try it. Maybe a good topic for a separate discussion.