I would say most of these guys, especially slappers, are muting strings with their thumb over the top. I do this sometimes as well. Good muting is essential to the more aggresive techniques.
And louis johnson does some fretting with his thumb. Looks crazy but it allows him to slap hard and mute strings.
And louis johnson does some fretting with his thumb. Looks crazy but it allows him to slap hard and mute strings.
