You can edit most voices this way... just by edditing the envellope (adsr)..
A bit more sustain, and a lot less release, in general will do the trick...
Thanks Bachus. Unfortunately I found that Roland BK-5 doesn't support tone editing...

_________________________
'For a day in your courts is better than a thousand elsewhere' (Psalm 84:10, ESV)
Past: Roland (E-10, E-16, E-38), Korg i30s.
Current: Roland BK-5, Kurzweil MicroPiano.