I've been watching a couple guitar covers and noticed that some people put sponges on the headstock either over or under the top of the nut, like you know when the nut meats the headstock and the strings are going in the direction of the tuning key, like they put the clothe or sponge right on the strings or under the strings over the nut, what does this do? sorry if this is the wrong place for this question.
It's to reduce ringing string noise, simply a dampening device.
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Quote by tappooh
They suck at muting strings so they have to use those lame ass tricks.

Oh okay, lets hear you do some advanced tapping and be completely clean.
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Quote by tappooh
They suck at muting strings so they have to use those lame ass tricks.

Ya because Guthrie Govan and Andy James just suck at muting strings
Quote by tappooh
They suck at muting strings so they have to use those lame ass tricks.

Yeah, okay. Tell that to Guthrie Govan, Jennifer Batten, Steve Vai, Joe Satriani, Ethan Brosh, Angel Vivaldi and Eddie Van Halen next time you are playing with them.
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Quote by GuitarNewbee
nut meat

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If you mean between the nut and tuning pegs, as opposed to above the first fret, then that's to stop the strings resonating there. I use a hairband though. Without one I can hear the resonance from the headstock part of the strings come through the amp. Just helps to tighten up your sound in a place you don't put your hand.
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@everyone getting butthurt over my comment - read the OP, he said "I've been watching a couple guitar covers" not "I've been watching Steve Vai". I'm sure the players listed above would play just as well without damping the strings, besides there are players that dont use those at all and still sound very clean.
A lot of people, even pros that have been playing for 30 years or more will use something like that in the studio. But they rarely - if ever - use them while performing. They're just used to help mute the strings. They can make a recording sound a lot cleaner and more precise, and also the recording process will be faster and easier. If someone is using it while performing, they either can't mute what they are playing properly, or they don't care enough to do so. Or both.
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If you where watching random youtube videos it's because they aren't great at muting strings and can't be bothered to learn how. Leave them a witty comment about how they suck and move on.

If you where watching somebody recording then it's probably just to make the process easier and quicker. A lot of professionals do it. I've never seen somebody do this live (or even a youtube video) and is pretty much something that should stay in the studio to make recording the process less complicated.
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