Guitar overdrive circuit based on CD4069 cmos IC. This digital logic IC contains 6 identical inverters composed of a complementary pair of mosfets. In this circuit they are used as analog amplifiers. Overdriving yelds a "warm" tube-like overdrive distortion sound. CD4013 is a dual D-register or flip-flop cmos IC. Here it is wired as bi-stable flip-flop and output Q is half the frequency of clock input. In music, one half frequency is equivalent to one octave below. Balance potentiometer sets the ratio between overdrive and sub-octave signals. Keep in mind that 4013 is a digital IC and will only understand a monophonic audio wave. Its output is a square wave with no envelope.
Step 1: Device Views
Step 2: PDF Download Link
Step 3: Circuit Diagram & Details
Step 4: Balance Potentiometer Sets Ratio Between Overdrive & Sub-octave
Step 5: Drive Potentiometer Sweeps From Soft-clip to Hard Clip Distortion.
Step 6: For More Details Watch the Video. Thank You!
Step 7: Sample Soundfile Link
only added a little delay to "sweeten"
Last minute mods: replaced R9 was 100K now is 47K. Added 470p ceramic cap in parallel with R12
simpletronic made it!