I'm designing my own active subwoofer. This is the preamp/filter. It looks OK in the sim. Am I doing anything terribly wrong?
The first stage is just a preamp and a level control. Then there's a lowpass filter. If r_cutoff=22k, I get about 100Hz corner frequency. I'm thinking of using a 50k stereo pot for R33 and R32. Next is a selectable inverter. Nothing fancy here. R49 is really a switch. Finally an allpass filter to allow the user to adjust the phase. The transistors and zeners are just part of a voltage dropper.
Anything extraordinarily idiotic that stands out?
The first stage is just a preamp and a level control. Then there's a lowpass filter. If r_cutoff=22k, I get about 100Hz corner frequency. I'm thinking of using a 50k stereo pot for R33 and R32. Next is a selectable inverter. Nothing fancy here. R49 is really a switch. Finally an allpass filter to allow the user to adjust the phase. The transistors and zeners are just part of a voltage dropper.
Anything extraordinarily idiotic that stands out?