3

Background

I have no experience with midi (other than what I've read online) and I don't yet have any midi equipment to play with (but I have several devices working their way through the mail system).

Question

Is it possible to have multiple midi keyboard controllers set to the same midi channel, but transposed to different octaves, controlling the same sound generator? Perhaps a better way to ask that is what problems am I likely to encounter having multiple keyboard controllers daisy-chained together that are set to the same channel?

Details

I'm getting a Memotron M2D sound generator - it only listens on one channel, but it has three voices that can be split across different key ranges of the 128 midi notes (C0 to C10 or whichever numbering you prefer). Eventually, I plan to midify an old organ pedal board and combine this with two (small) midi keyboard controllers so that I have a different voice for each manual. From all my reading, it seems like I should be able to set all these to the same channel, daisy chain them into the M2D and as long as I have the octave ranges set so they don't overlap and match the mapping in the M2D this should work. However, I can't find any discussion of merging multiple controllers into a single device (lots of discussions of chaining multiple controllers to multiple devices or one controller to multiple devices). From what I've read, the biggest potential problem seems to be that a controller may not merge the data it's receiving on the "in" port with the data it's sending out - i.e., it may simply drop all the incoming midi data and only send out it's own data. However, for dumb controllers (i.e., that have no sound generating ability, like the Arturia Keylab) I can't imagine why the data coming into the "in" port wouldn't be passed along to the "out" port, so something like the example below should work (in my mind).

keyboard 1 (chan 1) -> Arturia keyboard 2 (chan 1) -> M2D (listening on chan 1) 

But, I have zero experience with midi at this point.

2

Yes this should work as long as you are MIDI merging or not stripping the incoming MIDI on any but the first controller. Most controllers allow MIDI merge and usually have it configurable, or they have a dedicated MIDI Thru port, which is what you should use if a controller has it. If you don't mind playing the same note twice, you don't even have to make sure the octave ranges don't overlap. For example, I have connected two keyboards with the same channel number to one tone generator and then played one with the left hand and one with the right and played the same sound in different octaves. I also have a foot controller and have done the same thing. If you are sending note on messages for different notes on the same channel, I can't see any tone generator caring (or even knowing) that those messages are from different controllers.

If you don't mind putting a computer into the mix, you could instead route the different controllers into a laptop separately and then merge the MIDI in software before sending it out to the tone generator. This solves the MIDI merge problem and gives you some other options as well, but does involve having a computer around and any necessary MIDI interfaces, but does let you easily use any USB MIDI controllers.

What a tone generator does with two different overlapping note on messages for the same note at the same time I expect would vary from tone generator to tone generator. The back of my mind seems to be trying to tell me that a multi-voice generator that I have will actually play the same note in more than one voice, while a mono synth that I have will merely re-trigger the gate while maintaining the same pitch CV output. I can experiment if you really want. Again, it will be specific to the synth/tone generator. Also, it doesn't seem like you are trying to send multiple note on messages for the same note, so it's really more of an academic question of mild interest.

  • From what I can see on the specs, I won't have a thru port - and I definitely want the signals merged as my tone generator only has a single midi in port. I'm trying to avoid using a computer (for now) just to keep life simple. It's comforting to hear of real experience with this working =) – S. Burt Dec 14 '15 at 21:25
  • 2
    If you only have one device that won't merge and has no thru port, just make that the first device in the chain. Most controllers/synths do have manuals online so you should be able to verify whether they have a merge function before you buy or even if you can't find the manual. – Todd Wilcox Dec 14 '15 at 21:26
  • 2
    I tried this tonight with two keyboards and a four-voice analog synth module just to be sure. It worked - no problem. The question of the same key going to the same voice was answered by this module with the second note overriding the first. If I play C4 on keyboard one, then play C4 on keyboard two, and then release C4 on keyboard two while still holding C4 on keyboard one, the note stops. Keyboard one's C4 is overridden by keyboard two and keyboard one loses its control of the note. Again, I expect this would vary from module to module. A multi-layer piano module probably would not do this. – Todd Wilcox Dec 15 '15 at 3:04
2

If I understand your description correctly, I think there might be problems with some midi messages applying to all 3 controllers. In addition to the number of the note being played, there is also control information. Some control info applies to the note, such as a velocity values, note on/off, etc. Some control data applies to the whole channel. You might wind up with one keyboard sending midi info that would affect the other notes on the same channel, even though each keyboard was sending different note on/off messages. But the next question would be why have multiple controllers? You can "record" the midi notes separately and edit them so playback is from a single, clean source.

  • Pitch bend would certainly apply to the whole channel, but that seems like it would be desirable to me. Also, aftertouch could be implemented as a channel value or as an individual note value, but again, channel aftertouch is not usually a problem. – Todd Wilcox Dec 15 '15 at 3:01
  • I'm sure there are situations where my intended setup could run into problems: however, the motivation for this setup is that my existing keyboard is a cheap yamaha with no controls at all (no pitch bend, no knobs or buttons, etc. just 61 keys) - I purchased the small arturia keylab to get pitch bend, mod wheel, programmable knobs/sliders, etc. My plan is to shift the octave of the keylab so it won't overlap with the notes on the yamaha at all (if I ever get around to converting an old organ pedal board, I'll shift that down to the lowest two octaves to avoid any collisions) – S. Burt Dec 15 '15 at 16:14
  • As for recording and playback - I don't have any DAW software at the moment, and I probably won't move that direction for some time. Once the memotron shows up, I just want to be able to be play it "live" without needing to fight with any software playing middle-man. – S. Burt Dec 15 '15 at 16:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.