default velocity-to-attenuation curve is incorrect

[mrbumpy409]

The default velocity-to-attenuation curve for a SoundFont voice should be 96 dB deep. TinySoundFont, however, uses a 48 dB curve, reducing the velocity-controlled dynamic range by half.

Here is a screenshot of the recording of Test 13-A in the SoundFont Spec Implementation Test (TinySoundFont on top, FluidSynth on bottom):

You can see that TinySoundFont is not reducing the sample volume enough as the note-on-velocity decreases.