Hi CatOrg;
I think I understand what you are asking...
The releases are recorded into the sample set so that while playing, you can experience the effects of playing in the room where the physical instrument is. This is more a necessity where the original acoustics are generous.
Hauptwerk provides a means to truncate the release tails and I used this feature to remove the effects of playing in the original space since my VPO is in a church that has 1.4s reverberation and I didn't want the sound fading toward the speakers rather than decaying naturally in the sanctuary.
I think (and could be wrong...) that the determining factor on which release is chosen while playing has to do with how long a note has been held rather than the velocity of the attack or release. The reason I think this is that the sample set I play on Sundays has only one recorded attack and two release tails. My keyboards are capable of sending velocity information but it is ignored.
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