Here you can find schematics for various audio filters typically found in synthesizers or used to process audio.

• Aries AR-314 Lowpass Filter
• Diode Ladder Filter - Similar to EMS
• JH's SSM2040 Filter Clone
• Korg MS-50 Filter & VCA
• Korg PS3100/3300 Resonator Part 1
• Korg PS3100/3300 Resonator Part 2
• Moog Minimoog Filter
• Oakley Sound Systems Filter Box
• Tau 1010 Ladder Filter - PDF

Thanks go out to the following people: