MIDI-OX User Forum - Print Page


    
      
        MIDI-OX User Forum
        (http://www.midiox.com/cgi-bin/yabb/YaBB.pl)
      

        MIDI-OX >> Mapping Questions >> Mapping/transforming keyboard notes down an octave
        
(Message started by: swayzak on Jan 3^rd, 2011, 11:32am)

Title: Mapping/transforming keyboard notes down an octave
Post by swayzak on Jan 3^rd, 2011, 11:32am

Hi

I'm having great fun with my old Rebirth, and have worked out how to record controller data in Cubase/Reaper etc. for Rebirth.

I'm activating Yoke 3 as a Midi Output in the host & setting Rebirth to receive from Yoke 3 - seems a good workaround of the lack of direct Midi communication via Rewire.

However a lot of the note-based commands (ie. pattern changes etc) are down at the -1 octave level (e.g C -1, C#-1 etc.) & my keyboards don't appear to go lower than C0.

Would it be straightforward to set a MidiOx profile that allows me to extend the bottom range to this level ? Would it make sense to do this after the Midi has left the host, so as to not interfere with use of these keyboards for other tracks ?

thanks

swayzak

Title: Re: Mapping/transforming keyboard notes down an oc
Post by Peter L Jones on Jan 3^rd, 2011, 2:03pm

There is no standard for octave numbering. What note numbers are you referring to?

Yes, it's very straight-forward to have MIDI OX add or subtract 12 (or any other value) from a range of note numbers.

Title: Re: Mapping/transforming keyboard notes down an oc
Post by swayzak on Jan 4^th, 2011, 7:14am

on 01/03/11 at 14:03:03, Peter L Jones wrote:

thanks

The note numbers are those listed in the Rebirth manual & are as I listed them e.g. C -1, C# -1 etc.. My keyboards go down to the notes listed as an octave above these e.g. C0, C#0, but not down to this final octave.

For instance, my old Ensoniq only goes down to "C0" as listed in the Rebirth manual ...

http://static.upillar.com/pictures/resources/33441/supersize/ENSONIQ_Digital_Electric_Piano.jpg

Title: Re: Mapping/transforming keyboard notes down an oc
Post by Peter L Jones on Jan 4^th, 2011, 7:29am

"C-1" isn't a note number - it's a note letter and a relative octave indication. MIDI note numbers range from 0 to 127.

Unless you know what the relative octave indication of, say middle C is in all circumstances, you can't compare "C0" and "C-1" meaningfully.

Title: Re: Mapping/transforming keyboard notes down an oc
Post by swayzak on Jan 4^th, 2011, 9:48am

Here is where I think middle C is (I'm not at keyboard at the moment to check) :

http://img521.imageshack.us/img521/9184/pianoy.jpg (http://img521.imageshack.us/i/pianoy.jpg/)

And the bottom note produces the message associated with E0 (in Rebirth manual).

So I need to extend the bottom end another octave (to cover the messages of "C-1" to "B-1" ...

PS Actually I'm thinking maybe transforming Midi notes as they come into the host might be better e.g. from within host itself, rather than using MidiOX ? I think Cubase has this function ... ?

Title: Re: Mapping/transforming keyboard notes down an oc
Post by Peter L Jones on Jan 4^th, 2011, 1:12pm

OK, sounds like you're using the same naming between the two at least (i.e. not just taking it on trust that what Rebirth calls E0 is what you're keyboard calls E0). Anyway, see this page, particularly the "Errata" at the bottom:
http://web.archive.org/web/20080115121223/www.borg.com/~jglatt/tutr/notenum.htm

Middle C is what you're calling "C3". That's note number 60 ("by definition"). That means there are five octaves from MIDI note 0 up to middle C (60 / 12 = 5), meaning you need C-2 to be your note number 0.

I'm lucky in that my keyboard (an old Evolution MK-249) has an octave shift function built in.

However, you can easily shift octaves with MIDI OX (or any other interval you like). Just create a Data mapping for Note On (and Note Off, to be safe) that maps the input range to an output range offset by the amount you want. This way you can decide maybe you only want to offset the bottom octave, rather the whole keyboard range.