I’ve self-sourced parts (components and PCBs) to make Ambika SVF filters and just finished my third one. With all three, I’ve had to turn the trimmer fully counter-clockwise to approach v/oct, and it’s still not quite there on any of them. I’ve made and properly tuned 12 SMR4 filters, so I’m confident my tuning procedure is correct. Is this a common issue with the SVF or did I put incorrect components in there? I’ve double-checked my parts against the BOM, am using 68nf film caps instead of 33, as recommended, and aside from v/oct tuning they seem to sound and behave just fine. The tuning is close enough that I don’t think it’ll really matter except to give some extra flavor, but if I’m doing something obviously wrong I’d like to know.
You can try replacing R10 by a 30k resistor, and R23 by a 10k trimmer to get more tuning range.