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Originally Posted by: ptoolmanI found a single lesson on vibrato, basically covering the techniques used with some helpful instruction.
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Perhaps this one?

http://www.guitartricks.com/tutorial.php?input=703
[QUOTE=ptoolman]
I'm looking for more in depth tutorial on this technique ...

There are two important components to building proper technique, the physical aspect and the musical aspect.

Physical - you have to slightly change your approach in order to bend properly. Normally it's best to keep your thumb in back of the neck applying opposing pressure to your fingers. But when doing bends or wide vibrato, it's better to slightly alter your hand position to "hang your thumb" over the top edge of the neck, with the base of your index finger on the other edge for counter leverage. This gives you more control.

Musical - you have to practice hitting the right pitch. Practice bending a little bit and then gradually wider. At this point you are still just trying to wiggle the string back and forth a bit, but stay centered on the original pitch. This gives that "singing" tone. It keeps the string ringing and the note happening. Next you practice changing the pitch by playing a note, then bending a lower note up to that note. Start with half-steps, move to whole steps, then one and a half steps, etc.

These tutorials show more on vibrato and bending.

http://www.guitartricks.com/tutorial.php?input=723
http://www.guitartricks.com/tutorial.php?input=346
http://www.guitartricks.com/tutorial.php?input=217
http://www.guitartricks.com/tutorial.php?input=312
http://www.guitartricks.com/tutorial.php?input=628
http://www.guitartricks.com/tutorial.php?input=335
http://www.guitartricks.com/tutorial.php?input=295
http://www.guitartricks.com/tutorial.php?input=294
http://www.guitartricks.com/tutorial.php?input=475


Best of success!