Re: [fluid-dev] [PATCH] Requested changes to FluidSynth

[Josh Green]

Hello Chris,

The whole attenuation issue with Creative Labs sound cards has been
discussed before in regards to FluidSynth, but I don't think it was ever
resolved correctly.  As you noted, they do not follow the SoundFont spec
in this regard.  I've contemplated whether FluidSynth should just resort
to AWE 32/64/Live!/Audigy compatibility mode when the SoundFont
indicates that it was made for one of those devices (EMU8000, EMU10K or
others ??? in the Sound Engine field).  If you have any ideas in this
regard, that would be great.  I imagine Swami and other SoundFont
editors should probably follow this anomaly as well.

Cheers.
        Josh Green

On Thu, 2008-07-17 at 02:28 -0500, S. Christian Collins wrote:
> Well, I have found a problem with the change I made to the velocity
> scale.  While it improves the velocity responsiveness, as well as
> related controllers (volume & expression), it messes up the
> attenuation level as set within the SoundFont.
> 
> On the Live!/Audigy, setting the attenuation to 8 dB actually
> attenuates the signal by about 3.1 dB.  The unmodified FluidSynth will
> attenuate the same patch by 2.9 dB, so it's pretty close.  However,
> with my change, the attenuation is now exact to what is set in the
> SoundFont (so setting it to 8 dB actually attenuates it by 8 dB).
> Honestly, I don't know why the Live!/Audigy synth is set up the way it
> is, because you would think that setting it to attenuate by 8 dB
> *should* actually attenuate by 8 dB.  However, since most SoundFonts
> expect a Live!/Audigy type response to the attenuation setting to
> render correct sound balance, this should IMO be fixed in FluidSynth
> to avoid breaking compatibility.
> 
> I will peruse the source code to see if I can find what to change so
> that the velocity curve can remain modified, but since I'm not a
> programmer, maybe someone else here might be able to find it more
> quickly?
> 
> Anyway, time for bed for me--2:26 am here...
> -~Chris
> 
> Josh Green wrote: 
> > On Sat, 2008-07-12 at 11:21 -0500, S. Christian Collins wrote:
> >   
> > > Dear FluidSynth developers,
> > > 
> > > I have created a compilation of changes that I have made to the
> > > FluidSynth code.  You can view the changes in PDF format by
> > > downloading from this link:
> > > 
> > > 
> > > http://www.schristiancollins.com/temp/20080711_changes.pdf
> > > 
> > > 
> > > I would like to propose that these changes be implemented in the next
> > > version of FluidSynth (1.0.9?). I would like to publish SoundFonts
> > > designed for FluidSynth, but my SoundFonts will require some of these
> > > changes in order to function 100% as designed. I hope you will agree
> > > that these changes are for the better of FluidSynth and consider their
> > > inclusion in the project.  Please let me know if anybody has problems
> > > viewing the PDF.
> > > 
> > > 
> > > Thank You,
> > > S. Christian Collins
> > > 
> > >     
> > 
> > Hello Christian,
> > 
> > Nice to hear of your changes and work to make FluidSynth synthesize in a
> > more expected manner.  I'm currently traveling and will be back home in
> > a few weeks.  Its long overdue for me to put in some time into
> > integrating the various changes that users have sent.  Thanks again for
> > the contributions.
> >     Josh Green
> > 
> > 
> > 
> >