[sdiy] amateur question about modifying the ms-20 ota filter

[Emily Straight]

i'm tweaking the rene schmitz <https://www.schmitzbits.de/ms20.html>
implementation of the ms-20 filter for a project, and i was hoping to use
the emitter followers on the 13700 rather than separate op amps if
possible, it seems, like, vaguely wasteful not to or something. in
simulation this is resulting in killing the resonance on the negative side
of the waveform, however. is this because of a mistake i made setting it
up, or is the 13700 buffer fundamentally unsuited for the purpose? i found one
schematic <https://aisynthesis.com/wp-content/uploads/2020/05/MS20v2.5.pdf>
that appears to do the same thing so i'm guessing the former, though idk
maybe theirs sucks too lol. i also put a vca in the feedback path rather
than a potentiometer, maybe that's causing problems? i have essentially
zero experience in analog electronics if you couldn't tell

thanks <3
-emily
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