SoundFont synth compatibility chart

	A	B	C	D	E	F	G	H	I	J	K
1		Audigy 2 ZS	bismark bs-1/bs-16 v4.1	DLSMusicDevice (Mac)	FluidSynth 1.1.6	Jeskola XS-1	LinuxSampler 2.0.0	sfz	SynthFont2 v2.0.2.2	Timidity++	VirtualMIDISynth 1.16.0

2	1. volume envelope			attack is linear		ignores delay value				decay incorrect
3	2. modulation envelope		attack is linear	attack is linear wrong mod. amount	attack is linear	ignores delay value attack is linear	attack is linear	attack curve has initial jump		broken / not supported
4	3. key number to decay					values are inverted		decay amount too exaggerated
5	4. key number to hold							hold amount too exaggerated
6	5. modulation LFO			not interpreting values correctly			LFO starts at low point instead of middle			not interpreting values correctly
7	6. vibrato LFO			not interpreting values correctly			LFO starts at low point instead of middle			not interpreting values correctly
8	7. mod wheel to vib LFO
9	8. scale tune / root key
10	9. filter cutoff	low cutoff = 100 Hz, filter fully open at 8,000 Hz**	cutoff @ 20 Hz = fully open, 50 Hz and up = correct (test doesn't check 21-49 Hz)	filter fully open at 3,000 Hz			filter not very strong, perhaps pole-1?	low cutoff = 100 Hz	filter @ 20,000 Hz quieter than 17,500 Hz	filter fully open at 8,000 Hz	low cutoff = 100 Hz, filter fully open at 8,000 Hz**
11	10. filter resonance	highest value = 20 dB regardless of setting	highest value = 25 dB regardless of setting no attenuation at higher dB	not interpreting values correctly				no attenuation at higher dB	highest value = 25 dB regardless of setting	no attenuation at higher dB	highest value = 20 dB regardless of setting
12	11. attenuation amount	5 = 2 dB	5 = 2 dB	5 = 0.5 dB	5 = 2 dB	5 = 5 dB	not supported	5 = 3 dB	5 = 2 dB	5 = 1.7 dB	5 = 2 dB
13	12.a: default velocity to attenuation curve (96 dB concave)					curve a bit too extreme	incorrect curve	incorrect curve		incorrect curve
14	12.b: vel-to-atten curve @ 144 dB concave
15	12.c: vel-to-atten curve @ 48 dB concave
16	12.d: vel-to-atten curve @ 96 dB linear
17	12.e: vel-to-atten curve modulator removed
18	13.a: default velocity to filter cutoff curve	***	always has moderate vel-to-fc curve applied****	vel-to-fc not supported	no curve by default***	vel-to-fc not supported	always has moderate vel-to-fc curve applied****	vel-to-fc not supported	vel-to-fc not supported	vel-to-fc not supported	vel-to-fc not supported
19	13.b: vel-to-fc custom curve
20	14. CC1 (mod wheel) to filter cutoff
21	15. sample offset								seems to be using wrong values?
22	16. reverb		instrument reverb not supported, only CC91			only active when CC91 = 64 or higher?		instrument reverb not supported, only CC91		instrument reverb not supported, only CC91
23	17. chorus		instrument chorus not supported, only CC93			only active when CC93 = 64 or higher?				instrument chorus not supported, only CC93
24	18. interpolation type	high quality	linear	linear	high quality	linear?	?	high quality	linear	high quality	linear
25	20. exclusive class
26
27		* - values are estimated
28		** - the filter doesn't seem to close any further than 100 Hz, regardless if it is set lower. The filter appears to be fully open at 8,000 Hz. There is no audible difference between filter values 8,000 and 20,000 Hz.
29		*** - the Audigy is correct, but the default vel-to-fc modulator is strange, featuring a secondary modulation source (switch) that makes no sense. FluidSynth is right, in my opinion, to leave a default curve out of their implementation, while allowing custom modulators to function normally.
30		**** - correct according to SoundFont 2.04 spec, but may cause compatibility issues with some SoundFonts due to Sound Blaster filters being fully open at 8,000 Hz. This means that in instruments with high filter cutoff values (11-20 KHz), it is not possible to perceive the filter cutoff changing with velocity on Sound Blaster hardware. My recommendation to SoundFont synth designers is to ignore the default velocity-to-filter cutoff modulator altogether. Read more about this here:
31		SoundFont Synth Notes and Observations
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