CV Hex Noiser

Here is a fun little noise project that you can hook up to your Baby 8 Sequencer to get some gnarly sounds.

Taking CV (control voltage) from your sequencer or another synth the POTAR CV Hex Noiser creates funky noise beats, bleeps, and squelches in time with your setup. Don’t have a sequencer? No problem, this thing makes plenty of racket without one. I do plan on creating a Veroboard layout for a 16-step sequencer in the near future.

How does the CV Hex Noiser work?

Here is how it works. The CD40106 is wired into 3 Hex Schmitt Triggers (with the remaining open oscillator grounded to prevent unwanted noise). VR2 & VR4 control oscillator 1, which is bridged via a diode to oscillator 2. VR3 controls oscillator 2 which is bridged to oscillator 3. This is where your CV signal is introduced. The output of the CD40106 is then fed to a low pass filter (VR1) and is then routed to the 6418-powered pre-amp.

To make the layout a little easier to follow the jumpers are color-coded. In my layout design, the dark green wires represent the audio signal, the red represents power, and the black is ground.

This layout runs on a standard 9 volt, negative ground wall wart like the One Spt, PigHog, Boss, etc.
The IC7660S works a voltage doubler to get almost 18 volts to the 6418 pencil tube. The IC7660S can be omitted and the design can be modified to run on 9 volts, but it really sings at 18.

Currently unverified, but I have built a very similar design with an LM386 instead of the JAN 6418.

This layout is ripe with modifications, and I am sure prime for improvements. Let me know what you build!

POTAR Design Devices Hex Noiser and Baby 8 Sequencer
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