Eric Scheirer wrote:
>
> >> "Some keyboard instruments implement release velocity
> >> where a Note-Off code accompanied by a 'velocity off'
> >> byte is used. A receiver must be capable of recognizing
> >> either method of turning off a note, *and should
> >> treat them identically.*" (emphasis added)
> >
> >"should treat them identically" should be interpreted as : "a noteon with
> vel
> >0 should be treated identically as a noteoff with vel 64" imo.
>
> Yes, I agree. But there is no hint of giving any semantics
> for this byte and the section on velocity does not mention
> it at all. I have just sent a note to the MIDI spec people
> asking for a note clarifying this from their point of view.
> At the time this decision was made, we were *specifically*
> encouraged by the head of the MMA *not* to support noteoff
> velocity because many MIDI people view it as a confusing
> misfeature in their spec.
>
> >In this case, why the hell did you implement noteon velocity ? Couldn't it
> >have been done likewise with a controller ? ;-) No of course it couldn't,
> >because a controller is a channel message (the same for all notes at any
> given
> >time) whereas velocity (whether on or off) is a part (important imo) of a
> note
> >message, ie it can be different for two notes pressed (or released)
> simultaneously.
>
> You could use poly aftertouch if you like.
I would expect noteoff velocity to be widelier implemented than poly
aftertouch, since it is much cheaper to implement (the hardware --two switches
per key--is already there for noteon velocity)
> In any case, noteon velocity has
> important, useful semantics in MIDI which need to be preserved. This is
> not the case for noteoff (can you give me an example of what I should
> reasonably expect from a device as a content author when I send it noteoff
> velocities?
If I designed the instruments (as I should be able to with SAOL) I would
expect noteoff velocity to have an influence on :
- bowed strings release sound
- winds release sound
- expressivity of synthetic sounds, anything I like really : i find it a pity
to reduce expressivity of MIDI that's all. Enough from me on this.
> Is there content that makes important use of noteoff velocity?)
>
> >Moreover the absence of noteoff velocity is a blatant exception : it's the
> >only feature of MIDI channel messages which is lost in SAOL.
>
> That's not exactly true -- many of the GM controller semantics and
> the Omni commands have been lost, to avoid burdening the SAOL spec by
I was talking about channel messages : I believe noteoff velocity is the only
missing bit in those.
> making it try to act like a GM device in all cases. MIDI semantics
> are provided in SAOL as a convenience and for ease of porting (note,
> not "using") existing content to MPEG-4. But MIDI is not the
> primary control language in MPEG-4 and in the long run we'll gain
> more by moving away from MIDI than by trying to strictly preserve
> backward compatibility (particularly for the marginal aspects of
> MIDI like noteoff velocity) in all things.
>
> The upshot is, if you want fancy control over SAOL, use SASL. That's
> what it's for.
>
> >In conclusion I share the common conception (you can hardly call it
> >misconception, as I said above) that noteoff velocity is a useful and
> >expressive feature. However I realize that it may be a bit late to express
> >such an opinion, I can only hope that a future version of SAOL will correct
> this.
>
> Please don't misunderstand--I am archiving all concerns that are articulated
> about SAOL structure and function so that when it comes time to think
> about corrigenda or additions to the standard, they can all be discussed and
> considered fully. So I'm not ignoring or dismissing your complaints at
> all (after all, I'm not the owner of SAOL, ISO is), just trying to
> articulate
> why the decisions that were made, were made.
-- Greetings, Michel ......................................................................... Michel Jullian Directeur General email mj@exbang.com Exbang Industries S.A. Mas Chauvain route de Villeneuve tel +33(0) 499 529 878 Maurin 34970 Lattes France fax +33(0) 499 529 879 .........................................................................
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