We made a family trip to the local surplus store and I found the perfect momentary switches for the passive mixer. I’m no whiz with finding components, I’m still just learning what things are called, but I’ve had a really difficult time finding suitable switches for the mixer.
My ideal would be the classic arcade style button hooked up to a microswitch, but I couldn’t find any double-pole, double-throw (DPDT so I’ve learned recently) variations. A single throw switch just breaks the connection. A double throw switch sends the connection to a different output. That’s the typical microswitch style I’ve seen. A double pole and double throw switch has two inputs and four outputs. That’s what I need for the mixer. It lets me wire up the relay, the slide toggle switch (also a DPDT style) and the momentary switch in series in a way that lets the relay alternate the flow to either output and have both the switches flip the direction of the connections, so that firing the relay or any of the switches all have the effect of reversing the connection order.
The idea is to wire the two outputs to different channels (really: different resonators) and be able to move a sound from one resonator to the other via serial triggers from a computer toggling the relay, use the slide switch to reverse the direction and keep it like that, and the momentary button lets me override the direction manually via button mashing. The mixer is wired so that each channel has two mixed inputs and two alternating outputs, so patching the inputs and outputs around will let me play with various routing configurations in an ad hoc way.
I found three different sources on ebay for footswitch-style momentary buttons that looked promising. They’re the sort you find in guitar pedals, but not the latching kind where you toggle and untoggle the switch with each press, they’re more like normal momentary pushbutton switches: press down to toggle, release to untoggle. Still, they all had the same latching-style resistance: a very satisfying clicking action that you kind of have to push through to fully toggle the switch. That makes it pretty difficult to button mash, and after trying all three sources and not finding anything better online I decided to just skip the momentary switches entirely.
These switches I found at axman are double-pole double-throw, they have the same sturdy panel-mount style as the footswitches, but a narrow plunger instead of the stubby footswitch type (I’ll have to find something to cover them with) with a wonderfully smooth action. No friction at all! They feel easy to press rapidly even with the pointy plungers. With some nice covers I think they’re going to be perfect. And just $1.50 a piece! The ones I could find online were way more expensive. (Still good to use as footswitches for a different project though.)