The ChiMoon Analog Sequencer.
- The sequencer is built from A CD4067 1:16 multiplexor, CD40193 8-bit Up/Down Binary Counter and a CD4514 4-bit Latch/4-16 Line Decoder to run the LEDs
- The reverb is right off the PT2399 spec sheet.
- The drum oscillator is custom and designed around a CD40106 Hex Inverter (Schmitt)
- 16 individual pitch controls with pink LEDs (to match the apple blossoms)
- Rear controls for volume, tempo, drum resonance and drum overall pitch and frequency.
- Rear controls for reverb attack, decay and repeat.
- Powered by a 9v battery which supplies +/- 4.5V to the circuits
Analog synthesizers are making somewhat of a resurgence. Now before you and I and everyone in the synth community get into a heated argument about “What real is”… let me just explain one concept. We live in an analog world. When I speak, my vocal chords vibrate causing waves in the air to transfer to you, where your ear drums vibrate from the air movement into electrical signals that get decoded into something in your brain. Want more… Google.
My point is that the entire sound, all of those subtle harmonics and imperfections are all there, mixed in with all of the sounds from everything else going on. That is Analog.
Analog is where I become spiritually involved with the music.. Imagine, music made from nothing else but voltages. Fantastic, wonderful, rhythmic music made from simple electricity and nothing more. Water pours over a canyon, turning big turbines that cause an electrical current to travel to your house, through the service panel and wiring into a power supply that sends a mere +/-12 volts of direct current cascading into a pile of transistors, resistors and capacitors… and some of the greatest music ever recorded is made. There is no interpretation, no machine, no instructions and no perfection…. Just volts, circuits and the audacity to experiment.
I love rhythm, especially drum circles and beats. I also love to dance or at least ‘feel’ music. I imagined myself in a post-apocalyptic period where stores, instruments and factories are gone. Modern society has crumbled and set us back a hundred years. How would we play or feel music? would we become tribal? I further imagined ourselves making all sorts of mad-maxian things. Even musical instruments. A step sequence opperates pretty much what it sounds like. The sequencer repeatedly plays a series of steps, where each step is a different or similar sounding tone. Sequencers can be much more complicated, but for this exercise let’s keep this simple. Drummers created rhythms by repeating a series of beats. Many may have different tones.
While playing around with a oscillator circuit, I got it to make a sound that had a drum potential. It had the same sound as you would hear in a Chinese New Year parade. Those drums they use with the big dragons. Anyway, I left the circuit on a breadboard for a while, moving on to work on other projects. A few weeks later, we visited a cool vintage shop down the street from our house, and found this.
It is a Yueqin or ‘Chinese Moon Guitar’. “Oh, it is perfect”! I said. I started thinking about the drum oscillator and what I could do with it. A stand alone drum synth could be made from an 16 step analog sequencer and add a reverb circuit to make it alive. There are dozens of schematics on the internet, I thought. This old instrument could make music once more. (Click HERE to see the video of the circuit on the breadboard). I just needed to ornament the finished instrument with a Chinese theme like apple blossoms or water lilies. Many of the controls and knobs used were also salvaged from old equipment.
For a demo video, go HERE.
For more images on the ChiMoon build go HERE.