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

[jimmy]

> Date: Fri, 18 Sep 2009 12:18:06 -0700
> From: 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