On an Aside With Switch-Based Patch Panels
While detailing my logic controlled 2x2 matrix switch, in my previous post from a few hours ago, I referenced making a matrix switch out of toggle switches and a product called Make-A-Bracket. I wondered whether it might do the job...
It actually might, except it's probably no less expensive than doing it with logic control! Maybe a bit less (holds up 2 fingers in a pich gesture), but as I detailed in the previous post, no EEPROM to store and retrieve settings, either. That's a sketch of the mid-century modern version up there . The main panel is the legendary, Australian (possibly Bunnings-only) hardware product that can get you a kludged project panel, housing or bracket without a 3D printer. It comes in various sheet and bent varieties, all predrilled to a 20mm x 25mm rectangular tesselation.
This stuff holds bits of my cargo bike together (including a very stylish diacomp BMX brake to classic side-pull mount brake adapter that actually fucking works! Yeah, I was surprised!), my studio, my workshop, various things I've bodged up for friends and stuff that didn't work, but not because of any failing on the part of Make-A-Bracket. I costed this matrix switcher with centre-off, DPDT switches (as shown) for stereo or balanced-line (around AU$220 or so with cheap-assed XLRs and a salvaged pallet wood housing) and with SPST toggles for mono, unbalanced line (around AU$150 including TS sockets) in the same housing. It's five in to 10 out. (Am literally thinking of it for my L-12, instead of the LC Matrix... BUT WAIT, EEPROM!!! Store and retrieve settings.) The logic controlled version is literally about AU$100 dearer for balanced line, or AU$50 more for mono.
So basically, five 6.5mm TRS sockets feed in to the left, from the Zoom L-12's monitor busses, "B" to "E" and are wired to the top right and bottom left (for right and left audio signals) of each of the first 4 rows of SPDT, centre-off toggles. (Yeah, doing it mono, with 10 L358 balun amps on the outputs.) Both centre pins of each switch are bridged and each are wired to the centre pins of the next switch above it, then to the balun amps, then to 10 6.5mm TRS jacks. That's it. It's that simple. Idiot proof. At any position, throw a switch right or left to select the left or right channel and feed it out on that column's output, ready for balanced line use by the L-12. My fifth row will be for instrument use, as I like to keep the "A" headphone channel for a separate control room mix. Trust me, watch a youtube video on soldering, and you will be able to make one of these without any help. Even if you don't know the difference between AC and DC.
Anyhoo, that was too many words for a curiosity.