Vibrato?

[jbarter]

I use both diaphragm and finger vibrato. They don't sound the same so I use whichever one suits the tune best.

[Mitch]

I'm not experienced enough to have proper control of the diaphragm type vibrato (working on it). In the mean time, I'm enchanted by the way different whistles behave using the Finger-tap method. Some give a soft "pop" while others do a pitch change, still others break into a wild upper-harmonic that's realy exciting - I like whistles that do a combination of pop and harmonic - it adds such character.