4-band Resonator/Filter

The device has four identical bands with BP filters. Also first band is switchable to HP mode and fourth band to LP to make low and high shelves. Also each band is switchable to boost or cut modes.

Every parameter has voltage control, also I plan master CV ins for all bands.

Controls are:

FREQUENCY is peak frequency of a band. Range is 10 octaves. V/oct responce and initial frequency are trimmable with trimpots. CV range is 0...10V.

BANDWIDTH range is from 2 octaves to 0.06 octave at 3dB point. CV range is -5....5V.

LEVEL range is 14dB. CV range is 0...5V.

LM4040 precise voltage source for all offset voltages.

Temperature compensation.

Filters are based on hi-end quality THAT2180 chips. VCA for resonance gain (level control) is discrete.

Chips used:

8 x THAT2180
2 x THAT300
3 x TL074 (for CV)
12 x dual opamps for audio. I will use OPA2604 but TL072 possible.

http://L-1.su/

• ? mA +12V
• ? mA -12V
• ? mA 5V

Available as an assembled Module and as a DIY project.

No info about availability.