I saw a video clip describing bonnie raitts vibrato. She does a 1 fret spread, fairly slow with no damping behind the
slide. She said she thought the overtones gave her a fatter sound.
I tend to do what the tune needs. I heard a neat trick for adding expresion to your vibrato. It is realy for finger vibe but, should work for slide.This guys sax teacher told him most people tend to do vibrato on the beat so it is very uniform. He told the guy to do the vibrato six times so it breaks out of the beat. He found applied to his guitar, it realy worked well but was realy hard to break from the more normal vibrato duration.It is worth a try.Let me know what you think.
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