There is a reverse cymbal in the Electric Drum Kit - SOUND EXPLORER > DRUM KITS > ELECTRIC KIT - the reverse cymbal is on note E2. It's much shorter than 3 seconds and I doubt if you can do much about it - even by editing the sample in the drum editing facility. I expect the sample is only of short duration, I don't think you will be able to stretch the sound to 3 seconds.
One way to achieve a longer sound is to use the Sequencer or Composer to record a series of 'E2' key presses, making the velocity of the key gradually greater, to provide the crescendo..........
The problem with the in-built sound is that the sound ends with a bit of a 'Click' so this may not be really suitable.
I have produced a 'normal' cymbal crescendo on several occasions, using both the Composer and Sequencer method.
You may be able to do something in the Sound Editor, if you can find a suitable 'Base' sample to start with - maybe white noise and some filtering and envelope shaping?? White noise is in group M of the samples.
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Willum
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Willum
After silence, that which comes nearest to expressing the inexpressible is Music.
Aldous Huxley
( especially when the music is played on a KN7000....)