Whammy bar dips

[SlickXQ]

In some vai songs and in a lot of satch songs like time, surfing and clouds race across the sky, they kinda chop the bar and its makes this great sound for the note they're fretting. Thing is, I've watch'd satchs dvd and seen vai play 'n stuff but I never see them pick the note or hold the fretted note and mute the other 5 strings, it just seems like they're chopping the bar and it works great. I'd love it if someone could explain cause maybe they are picking. if anyone knows what i'm trying to explain, any ideas/ suggestions would be great.
thanx,
Nik

[davester1234]

they're not picking...

you use the fingers on your left hand to mute the notes on other strings from ringing out. You have to be precise, if your sloppy with the left hand, they'll all sound.It takes practice to stop the others from ringing out, but with a bit of practice, it gets easy.

You have to push on a note hard with the left hand, and then tap the bar.

[SlickXQ]

Thanks alot, I'll give it some time when I get a chance.
-Nik