I was reading up on the technical aspect of the guitar and I was very intrigued. I learned that the guitar is basically an instrument that creates electricity using the concept of induced current ( made possible by the interaction between the pup and the stings). Anyway... Is it possible to actually measure the output current that is made while playing? How many volts or amps actually travel through the guitar's wiring? Have any of you actually thought of this?
technically, yes you can measure the output voltage.

But it's very hard to quantify something like this as the output voltage is determined by how large a signal you are generating which is determined by how much the magnetic field is changed which depends on the string vibration itself. If you could normalize and accurately quantify how hard you are hitting strings between pickups, then yes, I can imagine you could measure pickups that way. But otherwise, there is no real objective way to measure pickup output. Closest you can do is measure DC resistance, which albeit, is inaccurate but at least it's inconsistencies can be better accounted for.
Yes,

Depends on your pickup (single coils have less output)

and

yes
Quote by LedZepFan2000
I was reading up on the technical aspect of the guitar and I was very intrigued. I learned that the guitar is basically an instrument that creates electricity using the concept of induced current ( made possible by the interaction between the pup and the stings). Anyway... Is it possible to actually measure the output current that is made while playing? How many volts or amps actually travel through the guitar's wiring? Have any of you actually thought of this?

Current is effectively zero - the input impedance of the amp assures that. Not sure what voltage range to expect.
GMW hot-rod telecaster
GMW soloist
PRS Custom 24
The Illegal Les Paul
CAE 3+SE
Soldano SM-100R
Splawn 4x12

“Life is on the wire…the rest is just waiting” - Papa Wallenda
Substitute the stage for the wire, and he's got it.
1/8 volt average
As Sebi has already mentioned, the output of pickups varies greatly, and active ones will generally have much higher output than passive ones.

Usually guitar amplifiers have fairly high input impedances, often as high as 1 megaohm, but I've used 100K quite happily in the past.

Most guitars can put out a great deal more than 20mV, some (played hard) can reach 1V or so.

Any guitar circuits you find are likely to be designed to work with a guitar, so it doesn't really matter a great deal - you simply adjust the controls on the guitar, and the way you play, for the sound you want.
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