Hi Sherry,

" Have you tried out any of they KS (keyswitch) instruments? I don't what all JABB has, but I know for GPO, some of the KS instruments go from 'straight" to "vibrato" when you use the KS."

Yep! All the KS does for the brass instruments is offer the ability to go from "open" to "mute" on the fly.

Cheers,
Fred