Fri Dec 24 02:15:18 EST 2010

PIC-controlled hybrid synth

So it looks like I have most components to make the controller:

  - Diode ladder filter or SVF

  - 2 x Digitallty controlled exponential converter: linear reference
    and exponential control inputs, one each for:

    - filter cutoff

    - analog sawtooth generator (could use frequency feedback)

Components (ladder):

   * 2 x matched NPN pair

   * Opamps (couple for feedback too)

   * 8 x diode, 4 x cap

Components (SVF)

   * LM13700

   * 3 x matched PNP (3-legged exponential converter)

   * Opamps or transistors for buffers.