Not sure if necessarily a bug but, when converting different instrument formats such as SFZ or GrandOrgue to Soundfont the result is that the newly created Soundfont ends up with a very noticeable lower volume output than the original source instruments volume.
I have read something along the line that SFZ has a different default attenuation (volume) than Soundfonts, so when you do the convert it appears to result in the Soundfonts default attenuation which is a lower value, if that makes any sense?
Only available option in Polyphone that I know of is that you have to manually change the "attenuation" value before performing the export which can be tedious if want to convert many items. Also I use Polyphones command line export so unfortunately there is no way to do this with that converting method that I am aware of.
Something to note:
If you load the original SFZ instrument side by side in Polyphone with the exported Soundfont the volumes appear to be the same.
It is when you load them in other programs that you notice the difference.
Have to use a player / sampler that can load both SFZ and Soundfont to accurately test.
So for example the VST called RGC Audio SFZ can load both.
I have also tried this in FL Studio Demo as well as TX16WX (a while back) and I get the same results.
(Cannot use the popular Plogue Sforzando because it converts SF2 to SFZ when loading)
As mentioned the only program that does not show this difference in volume is Polyphone itself which is strange.
Not sure if Polyphone has some kind of gain matching property?
Hopefully there is a solution for something like this.
Anyways, Thank You so much for creating such an amazing program.