Mods and Alt Configs
Mods and Alt Configs:
Overall gain and LPF peaking gain:
For v1.0 the nominal overall gain before boost or Cut is set at ~2.5dB. LPF peaking at max resonance gives ~ 10.5dB of gain at the peak above that 2.5dB figure, or 13dB total. That may easily exceed available headroom with a 9V supply and some basses. While 6dB or so of peaking as a max amount gave good results for my own wants and needs, many testers felt that amount was too subtle when trying to dial in a target frequency in noisy environments. So for v1.0 I have taken it to 11, so to speak. We can always turn it down! But just subbing higher values for the two 4.22K resonance resistors (R11 and R14) will knock down the peak gain if that's desirable. 4.75K gives around 8.5dB of peaking gain and that would be a reasonable place to start taming things a bit. The stock config gives lots of meaningful and intuitive change between 10 and 2 o'clock though, which I see as a pretty good default mode.
Mid Switch 3 way switching using DPDT On-On-On switch:
Values shown give mid centers at ~ 700/1.56K/2KHz. Here's a spreadsheet using 1.5nF (1500pF), 2.2nF (2200pF), or 2.7nF (2700pF) as the smallest value, so going from 2KHz downward as progressively bigger caps are switched in: