Quote:
Originally Posted by
John Walton
➡️
i never really hear clicky attacks. one issue with Soundwell potentiometers is they have poor End Resistance specs. this is particularly noticable on the audio taper pots used in vintage monosynths - the audio taper matches the ears log response to volume. poor end resistance causes a 'jump' in the timing value as you move CW from fully CCW. very small resistances make a big difference in timing at the low end of the dial. the jump in timing accentuates the presence of minimum attack - which will usually sound clicky at about 800us or so. proper end resistance (and a smaller timing cap*) lets you smoothly change from clicky, to snappy, to fast and then moderate attacks (and decays/releases).
*-because it's a 9mm pot compared to the 24mm pots the circuits were designed for. the smaller pots just don't have the 'selectivity' of a physically larger component even with modern deposition techniques. there are many other reasons to replace Soundwell pots as well; while 'good enough', they're demonstrably not great.
the only trade off is no long timing, but i never use long timing anyway.
My B. Monopoly (other may probably behave different) presents critical Attack pot action at the far CCW end, where irregular distribution of resistance on the substrate does make -sadly- big difference. My Attack pots do jump very easily from 0 attack to several milliseconds in a short span, it's still possible to fine tune the timing with some effort. But the clickiness I meant, really a transient, is apparent when lowering to zero the volume of one or more VCOs. Arpeggiator in Poly mode (round-robin) is effective for locating the source of the click, for the record the transient can be masked by setting the smallest amount of Amp Attack right above zero (maybe 2 ms?).
Agree on the potentiometers quality, it would be a nice upgrade.
Re. timing capacitors: I would rather put a small lever switch for selecting normal/high speed by just adding an identical capacitor in series to the circuit. I would also do this tweak to MG1 LFO and push it into audio range, I tried the waveform switch trick with no success.