Re: dynamic and midi velocity

[Tim Reeves]

> Date: Thu, 18 Feb 2010 11:16:05 +0100
> From: "Bertalan Fodor (LilyPondTool)" <address@hidden>
> Subject: Re: dynamic and midi velocity
> To: Peter Chubb <address@hidden>
> Cc: miquel parera <address@hidden>,
>    address@hidden
> Message-ID: <address@hidden>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> Peter Chubb wrote:
> >>>>>> "miquel" == miquel parera <address@hidden> writes:
> >>>>>> 
> >
> >
> > miquel> I want translate the dynamics of one note (\pppp, \ff etc) to
> > miquel> midi velocity values (0-127) I'ts possible?
> >
> > Lilypond uses a separate volume channel, rather than velocity, to
> > control MIDI dynamics.  There's a perl script `ConvertToVeolcity.perl'
> > that can convert the midi output and add velocity info to each note.
> > 
> That's a bug then. Musically \p means velocity change and not volume.



Bert,

I'm curious what you mean by this comment. \p does not mean low volume but 
low velocity?
Do you mean you use (when you play an instrument) a low velocity (air 
velocity, velocity of striking a key or drum, velocity of bowing, etc.) in 
order to create a low volume (sound level) and so it's the velocity that 
you have to control?
AFAIK, MIDI velocity corresponds to the velocity of striking a key on a 
keyboard instrument (since that is what MIDI is usually controlled by, and 
modeled after) which is why things like pitch bends and other non-keyboard 
instrument specific effects are hard or impossible to represent in MIDI.
When I play the horn, I don't consciously think "low velocity" when I see 
a 'p' in my part. I think 'play soft'. My body reacts by reducing the 
velocity (and volume) of air going into the horn, but I wouldn't say it's 
a bug that I think 'p'=low volume or soft.
Bottom line, in *MIDI*, \p means velocity change and not volume. But 
*musically*, \p means low volume. MIDI is not music, but that's another 
discussion. ;-)
(There's a book out now, 'You Are Not a Gadget', that talks briefly about 
the limitations of MIDI and how we're kind of stuck with them since we 
enshrined MIDI as a standard.)

Tim Reeves