fbpx
Skip to main content

MIDI Forum

midi 2.0 note on/of...
 
Notifications
Clear all

midi 2.0 note on/off message - how many note numbers?

4 Posts
3 Users
0 Reactions
12.5 K Views
stefaan
Posts: 3
Active Member
Topic starter
 

Looking at the midi 2.0 note on/note off messages, do I understand correctly that it still supports only 128 distinct note numbers? Technically one could abuse the 'attribute' to add extra numbers but that would be a manufacturer-specific extension, so not much hope for cross-device compatibility (and if you use the attribute for note number, where do you then specify the tuning information?). With so many other specs becoming better this seems like some kind of oversight. The topic of more than 128 note numbers comes up in microtonal/xenharmonic contexts much faster than in traditional music.

Note that direct pitch control per note does not really feel like a proper solution, as it will result in a single midi note number being used for addressing several frequencies, which (as far as I understand) makes it impossible to play 2 or more of those frequencies simultaneously.

Edited to add: this is not a "theoretical problem" anymore. As an example consider this device: http://www.shapeofmusic.com/overview.php which offers 192 keys and currently has to work around the limitations of midi by using 2 midi channels to use all the keys.

 
Posted : 01/02/2020 10:01 am
Brett Porter
Posts: 7
Active Member
 

Hi --

This will become clearer when the spec is published, but it's called out in detail there -- the short answer (which may be confusing at first) is that if you use the 7.9 pitch attribute in the note on message, then the note number doesn't need to be associated with a single key; you can assign them sequentially (or however; you just need to be careful to not reuse a note number while it's still in use) in the same way that MPE rotates channel numbers.

 
Posted : 03/02/2020 1:16 pm
stefaan
Posts: 3
Active Member
Topic starter
 

Ok, so if I understand correctly, you suggest to dynamically assign note numbers to keys then. I'm not saying that technically it cannot work, but it does sound like it would complicate the design of instruments to the point where people may still prefer to use the 2 channel workaround.

 
Posted : 07/02/2020 5:33 am
Eric Bateman
Posts: 1
New Member
 

I believe the idea is to think of "note numbers" as if they were fingers on a keyboard. So when you press C, the controller assigns the pitch Middle C to "Note 1", then your next finger presses E it assigns E to "Note 2" and so on. For microtonal controllers like the one linked above, the controller would store a table of 192 pitch values and assign them to "notes" as they are played. The programming logic would be similar to managing multiple fingers on a touch screen.

 
Posted : 16/02/2020 10:14 am
Share: