CD4### IC's and circuits

HI all. I have a heap of CD40106 and other 4### series IC’s gathering dust. I have a bit of a soft spot for these IC’s and want to use them. Does anyone have any interesting noise, drone, drum etc circuits that I could use them in.


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Look around the internet for “Lunetta synth” .

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Hi Eric. I have made a few Lunetta type modules. Also went down the MFOS route.

I haven’t got 'round to building one yet, but I’m looking at Linear Feedback Shift Register (LFSR Wikipedia) structures for digital noise generation as well as other funky ideas. You can do a lot of this with the CD4000 series.

Logic Noise: Taming The Wild Shift Register | Hackaday looks like fun.

Here’s a eurorack module based on an LFSR 22 things to know about the Turing Machine Eurorack Module

There’s also a couple of pages on them in Hal Chamberlin’s Muscial Applications of Microprocessors book - and their use in drum synthesis.



There’s the Noise Bell with CD40106

A clock divider with CD4024

SUB with CD4013

Sample & Hold with CD4093

Wave Shaper with CD4046 and CD4040


Or look closer to home


You can use them to make a midi thru device (a 74LS14 does the trick as well). Very handy e.g. if you have a few mono synths / single channel midi devices and want to share one midi output of your midi interface between them. 1 input 5 outputs: