I was curious how the DGx0x series analog switches sounded and didn't want to breadboard a DG401 with the necessary buffers, output mixer, and the like so I created the board you see here.

Unlike other popular CMOS analog switches and muxes the DGx0x series analog switches are bipolar IC's. This means you can switch audio bipolar audio, negative control voltages and other sources that might baffle "normal" CMOS unipolar switches and muxes--think of the DGx0x as a CD405x mux that can run from +/- 12V rails. Forum discussion is here.

The DG401 uses CMOS logic for switching, on my bench anything over about 2.8V applied to an IN pin made the associated S and D pins connect.

This "experimenter's board" includes a 3.5" clock input as well as logic inputs A and B. To use an external clock, populate the entire board and plug your favorite square wave into the board's "Clock" input, but if you want to just put >2.8 volts to binding posts A and B you can leave off the 2N3094 transistors and their associated resistors.

For IN1 and 2 you can use audio signals, control voltages, or a combination of both.

The 3.5" mono "out" jack is a non-inverting sum of the 2 DG401's outputs.

For me the result was clean, click free analog audio. I recommend the DG401 for audio and control voltage projects that need solid state switches.

More detail about this PCB and the DG401 in this blog post: https://audiodiwhy.blogspot.com/2023/07/arp-2600-voltage-processors-part-four_19.html