Stereo switcher as MIDI switcher?

vibracero · 2023-06-21T18:11:10.569Z

So I’m embarking on a project with my Digitakt and a few other synths and wishing I didn’t need to involve a MIDI hub that requires power and computer configuration, and wondering if this is a potential solution.

So I will have a Pro3, a Digitakt, a Hydrasynth explorer, and a larger MIDI controller. I’m looking for a way to potentially send the larger keyboard’s MIDI out to any of the sound-producing devices.

If MIDI A works off of 3.5mm TRS jacks, would I be able to use a switcher like the one pictured to send MIDI from the keyboard to any one of my 3 devices? I don’t need to send MIDI to more than one simultaneously, I’m just looking to choose which one gets the MIDI in the moment in a way that is cheap and technologically simple. Would this do it?

chapelierfou · 2023-06-21T18:18:38.133Z

I don’t know, but that’s a cool idea, and I don’t see why this wouldn’t work. Beware of stuck notes, though.

darenager · 2023-06-21T18:22:14.360Z

Should work, try it, quite a cool and handy box anyway I might get one.

Worst case scenario is the volume control might attenuate the midi signal, but most midi can work on 3,3v anyway so if you are sending in a 5v midi source you might get away with it. If not it should not be too difficult to bypass the pot.

frekvencia · 2023-06-21T18:26:36.867Z

You probably need to use something that was actually made for MIDI.

Unless your stereo switcher is passive (made of mechanical switches only) then you will likely encounter problems due to incompatible electrical specifications.

You might also have issues because the signal frequency is higher than the audio signals for which your stereo switcher was designed.

darenager · 2023-06-21T18:28:44.165Z

This one might be better, no pot.

amazon.co.uk

TENEALAY M41（4 in 1 Out / 1 in 4 Out AUX 3.5mm Stereo Audio Input Signal Source...

Free delivery and returns on eligible orders. Buy TENEALAY M41（4 in 1 Out / 1 in 4 Out AUX 3.5mm Stereo Audio Input Signal Source Switcher, 4-Way Switch Selector Splitter Box at Amazon UK.

chapelierfou · 2023-06-21T18:30:07.623Z

frekvencia:

You might also have issues because the signal frequency is higher than the audio signals for which your stereo switcher was designed.

I highly doubt that. I don’t know MIDI’s rate, but certainly less than 10kHz.
Edit :

Capture d’écran 2023-06-21 à 20.30.531072×594 51 KB

warpigs330 · 2023-06-21T18:39:49.366Z

I think 31,250 bits a second is 31.250 khz right (for the clock signal)? I think there is a decent chance that any audio gear will have a cutoff frequency of 20khz, and the sharp edges of a data signal will have even higher frequencies than the fundamental clock, so your nice square wave clocks might be getting turned into more of a sine wave.

vibracero · 2023-06-21T18:41:24.303Z

Aha, I figured it couldn’t be this simple (or cheap.) thanks all for your responses. It so happens I already had an ESI m4u sent to where I’m going, guess I’ll keep it

idylmind · 2023-06-21T18:55:32.980Z

Retrokits

The RK-006 MIDI/Gate Master Hub

Ultra Smart, Ultra Small! The RK-006 packs 10 MIDI / Gate Outputs plus 2 MIDI Inputs, USB Standalone Hosting and multiclock processing: Formidable portable possibilities!

Est. reading time: 4 minutes

warpigs330 · 2023-06-21T19:14:01.837Z

Funnily enough I think this might be more likely to work if you go really really cheap. Like you want to get rid of all the stuff that would filter audio for human ears, basically trying to get as close as you can to a straight line through the box.

darenager · 2023-06-21T19:17:08.687Z

FWIW I highly doubt these cheap audio switchers will have any circuitry aside from switches, jacks and if fitted a pot, so they should be ok for midi signals.

warpigs330 · 2023-06-21T19:18:41.798Z

Yeah, I think passive is probably a good bet.

darenager · 2023-06-21T19:27:24.205Z

I might get kicked out of the MMA for spouting such heresy, but it would probably be possible to have 2 switches active at a time, assuming no channel conflicts on the receivers and a high enough current midi source. Hacky yes and against the midi protocol, but all the while people are pronouncing mark2 as Emkaytwo and connecting 1/4” cables to their modular with a inline 1/4” to 1/8” adapter, and even manufacturers can’t accept that type A TRS midi is the standard, fuck it why not?

Mister_Wood · 2023-06-21T19:31:30.704Z

I think both of those you posted are passive, as there’s no power supply input, and should work fine… but I wouldn’t be changing output mid-stream.

Laser · 2023-06-22T05:52:03.921Z

My 2p:

Yes it will work if the splitter is passive, I do similar stuff with my TRS midi and its fine.

However…

I really recommend you go for a MIDI router!

You can pick up a cheap 2nd hand Iconnect MIDI4+ (or similar) for peanuts on Ebay.

Right now you might only want to split it simply, but who knows how you’ll feel in 2 years, or 5?

You may need to merge midi, filter, split, may have USB controllers. May want to sequence 3 devices from 1 device, etc.

Yes it can be a chore setting them up. But its not that hard and once its done its done, and you never have to think about it.

Give your setup room to grow!

g3o2 · 2023-06-22T06:47:35.143Z

CME’s product offering can handle this, albeit when you multiply the price per required WIDI product by 4, it will be roughly 300 EUR, the price of a pro MIDI hub. The advantage will be a small and cable-less solution and you can set up various groups of devices. It works great in the studio, I rarely have any issue, though I’m not sure I would want to fully trust it in a live setting.

Batmosphere · 2023-07-30T23:45:25.991Z

I’ve used a $10 passive audio-video switchbox to route one controller to four synths. If you use miniphone-to-RCA Y-cables, you can even flip one set of RCA plugs to convert TRS-MIDI A to B. (In other words, connect red to white and white to red.) I also wired up some DIN-to-RCA cables. I soldered pin 5 of the MIDI plug to the cable’s left (white) wire, pin 4 to the right (red), and pin 2 to the shield.

As @darenager guessed, enabling multiple outputs made a poor man’s MIDI Thru box, allowing me to layer MIDI modules. I just had to make sure no notes were sustaining when I switched off an output, because that would prevent the eventual Note Off command from arriving, causing stuck notes.

The cool thing about using a video switcher is that you get the extra yellow jack for each channel. I used that to route CV signals or monophonic audio. This photo is from my “Synth Hacks” column in Waveform magazine, where I described this hack in more detail. The monster eyeball is powered by CV.

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