A MIDI query

[Mark Hammer]

You'd think that, with over 40 years to learn this stuff, I'd know by now, but here's my question.

I am in the process of wiring up my basement "studio".  I have a bunch of different MIDI synths and tone generators.  A number of them are only MIDI-in, but many have in/out/thru.

If I feed one unit with MIDI in, does its MIDI-thru constitute a viable MIDI-in for another unit?  Can I daisy chain several units in this manner, or does it introduce lag?

Am I better off trying to make a MIDI splitter? (Note that I have a bunch of 12-18" MIDI cables that seem optimal for daisy chaining adjacent units)

[PRR]

https://gearspace.com/board/electronic-music-instruments-and-electronic-music-production/1221595-what-did-midi-thru-do-wrong.html

Didn't that used to be GearSluts? Anyway, take with grain of salt and maybe a pinch of penicillin, those dudes may be rabid.  

[Mark Hammer]

Went through my parts bins and found a half-dozen PCB-mount MIDI jacks, and another eight 5-pin DIN jacks (which would require drilling holes for screws).  Went through my music mag folder and found several MIDI splitter schematics that look dead easy, and I seem to have all the electronic components needed.

So I think I answered my own question.  Certainly the comments on the gearspace page indicate that the way to go.  If 6 thru ports isn't enough, I can always use the MIDI-through in those boxes that have one.

[ElectricDruid]

If I feed one unit with MIDI in, does its MIDI-thru constitute a viable MIDI-in for another unit?  Can I daisy chain several units in this manner, or does it introduce lag?

Yes, it's a viable MIDI In. That was the original idea of MIDI-thru, after all. Generally, MIDI-Thru is done with a gate (or a couple of gates, if they're inverters) hanging off the MIDI-In opto. As such, the signal that goes out should be nicely squared up, even if what came in was getting a bit droopy. And the delay from a couple of gates is nothing at all at MIDI's baud rate, so it's basically negligible.

Soft-Thru going to MIDI-Outs is a different question. "Soft Thru" literally means that the MIDI data has gone into a processor and then been sent back out again. As such, the lag is much worse and can easily be a few milliseconds. Depends on how well the code is written at that point.

Am I better off trying to make a MIDI splitter? (Note that I have a bunch of 12-18" MIDI cables that seem optimal for daisy chaining adjacent units)

No, you should be fine with the Thrus. Old DIN MIDI Timing isn't that tight anyway, so you won't notice any additional effect from the Thrus. If you start sending two-handed chords, pitch bends, drum patterns, and MIDI clock all at the same time, you'll start to notice the limitations of the baud rate!