I’ve noticed on some of the SFZ instruments in Linuxsampler there seems to be an unusually loud key-off sample volume. One example is the trombone legsus (1st patch in brass category) for linuxsampler. When played there is what almost sounds like a loud “echo” at the time of releasing the key. Is this a glitch in Linuxsampler or a glitch in the SFZ/sample volumes?
It could be some opcode on the SFZ that is not well-supported by LinuxSampler. You could try to tweak the SFZ to fix it. Also, if you could send a list with the “bad” SFZs, we could try to fix it or remove it from the collection.
I’m definitely not an expert at tweaking SFZ files, but can’t spot anything obvious in the files themselves. It seems the volume for the main sustain samples varies with note velocity but the release samples are always played at full velocity. Playing quietly sounds strange, with a loud bit at the end of a note, but playing loudly sounds better.
Edit: Just having a play about with some of the other SFZ sounds and it’s looking like it may be an issue for every SFZ that uses a release sample (several in the strings, woodwind and brass categories, stereo Rhodes and clavinet)
Playing the SoloTrombone through Sforzando on my laptop seems to get the right volume for the release sample.
Is the release sample played at the release velocity?
@riban It looks like that is indeed the case. Release velocity determines the release sample volume. Sforzando seems to use the attack velocity for the release sample. In all the years I’ve been messing about with midi I’ve never stopped to think that release velocity was a thing!
I wonder if there’s a way in SFZ format to force use of the of the attack velocity to govern the release sample volume? For me, using the release velocity seems to generally results in strange mismatches in volume when using a keyboard unless a significantly different playing style is adopted.
Release velocity is not often implemented in MIDI controllers. Most will send a fixed release velocity or use note-on message with velocity 0 which the instrument may interpret as a default release velocity (maybe 100). I reckon it would work best with a keyboard that sent MIDI release velocity but maybe what you suggest may be a useful patch for users without release velocity controllers.
I’m using a Roland digital piano as midi input device and it would appear to send proper release velocity info. Gently releasing the keys results in a much lower volume for the release sample. However, it’s very easy to get mismatched note on/off velocities and hence mismatched release volumes for the instruments in question.