"One is thick calluses, which you can only get from bending strings up and down. That’s a physical tool and you need that on all fingers.
“Also, the thumb should hang off the neck [ie, over the fretboard] almost all the time to give you something to pull against. Take advantage of the fact you’re a human rather than a chimpanzee or an animal that can’t grip things.
"Don’t play like your cat; play like a human! Look at Jimi Hendrix: his hands were more on top of the neck than underneath. Not only does that give you strong bending and vibrato, it also helps you mute the strings.
"If you watch Paul McCartney playing that D chord on acoustic in We Can Work It Out, you see his thumb hanging way off the neck to mute that E string. He might not be regarded as a virtuoso player, but don’t think about being a virtuoso unless you can play a D chord right! So much depends on the thumb.
“The reason I emphasise this is that I see a lot of people playing classical position when I’m teaching, with their thumb really low. For other styles of music that isn’t as applicable.
"Metal guitar is supposed to be this powerful, aggressive thing and I see guys with this dainty little technique made of tiny little motions – which you need to play fast – but I love hitting it hard, having strength and power. The exceptions are really athletic stretches or barre chords. The thumb and calluses play a big part of that!”
Our Paul Gilbert inspired lick needs two different fretting hand positions; we start with the thumb placed against the back of the neck to facilitate wider fret-hand stretches.
As you reach the string bend, change your grip to a ‘thumb over the neck’ position for extra strength and leverage. Bracing two fingers together to bend the string helps too.
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