Re: [fluid-dev] Re: FluidSynth tuning and more commits

[josh]

Quoting jimmy <address@hidden>:
> > I'm a little bit perplexed in regards to the tuning
> > routines though.   
> > It seems that it allows for arbitrary per MIDI note
> > tuning 
> > modifications, using floating point values in cents. 
> > Tunings are 
> > added by instrument bank and program #s.  What is
> > strange, is that it 
> > seems these tunings only take effect when
> > fluid_synth_select_tuning() 
> > is called, to activate an existing tuning on a given bank
> > and program. 
> >   What is strange, is that this is never called in the
> > FluidSynth code 
> > base, meaning that tunings will only be active if an
> > external 
> > application activates them, which seems to defeat the
> > purpose of 
> > bank:program tuning assignment.  It seems to me like a
> > tuning should 
> > be automatically used when a bank/program change occurs, if
> > there is 
> > an assigned tuning for the given bank/program.  The
> > tuning 
> > infrastructure should probably also be integrated with MIDI
> > tuning 
> > standards, for assigning tunings via MIDI.  It seems
> > like the tuning 
> > system is currently not entirely complete.  Any
> > opinions on this?
>
>
>
> I'm not at all familiar with Fluidsynth tuning usage, nor the code.
>
> I only know that with MIDI controller(s) often allow hardware knobs,  
>  sliders, or pitch-bend wheel to manipulate a note's pitch.  It   
> allows one to play a note, turn the pitch-wheel, and the note pitch   
> can be raised, or lowered to a different note range.  The pitch   
> wheel are often used to bend a note like slider guitarist would move  
>  the slider after a string has been struck.  More often, I have seen  
>  keyboards that can program the pitch-wheel to bend a note up   
> 1-semitone up/down (2-semitone range all the way to 1 full octave   
> up/down (2 full octaves range) for the knob/slider/wheel physical   
> range.  The pitch wheel has springs-like hardware like a joystick to  
>  keep it at center if not held down, the default is normally   
> 2-semitones up and 2 semitones down for the full range of the knob.   
>  So pushing it up all the way will change the sound  by 2 semitone,   
> push part of the way gives a proportional pitch shift of that   
> 2-semitone range, releasing it and the sound
>  revert back to the original note.  Pushing down just does similar   
> thing for 2 semitones down by default.
>
> Some keyboards also have modulation wheel which doesn't have spring   
> loaded.  It allows sound modulation (note vibration) for emphasis on  
>  some notes playing live.
>
> So generally, live playing needs some real-time sound synthesis for   
> some individual notes.
>
> Of course, for people who work with soundfont, or some particular   
> instrument range and want to try to tweek and listen to to all the   
> samples with such adjustments, then the per bank/program selection   
> might be the way to go for them.
>
> Jimmy

Hello Jimmy,

FluidSynth already implements MIDI pitch bend, bend range and  
modulation (probably from the very first version).  The tuning system  
that I'm describing isn't related to that.  But instead allows for you  
to change the tuning of the note scale.  So you could use some other  
tuning scale besides the traditional 12 note equal temperament  
diatonic scale.  The MIDI standard in particular that I'm referring  
to, is the MIDI Tuning Standard:

http://en.wikipedia.org/wiki/MIDI_Tuning_Standard

I don't believe this is currently implemented in FluidSynth and is  
what I'm proposing is merged into the existing tuning system.  Hope  
that clarifies things.

Regards,
Josh