Op Amps: Biquad Filter

[@bob_mosavo]

Thanks Prof. Fiore 👍

[@StealthParrot]

Interesting filter. Thanks Prof.

[@mr1enrollment]

what cad tool is that?

[@ricobass0253]

Interesting - never come across this before. I'd call it an economy state variable filter. I associate the name, Biquad, with the Friend single op-amp circuit.