what makes the pitch of a guitar? If you use a rubber band there’s also different pitches but they don’t have frets


what makes the pitch of a guitar? If you use a rubber band there’s also different pitches but they don’t have frets

In: Physics

It’s the same thing, there’s fretless guitars.

The frets just give you specified intervals between tones by varying the length of the string that’s free to vibrate.

Violins work on the same principle and they’re also fretless.


Sounds is basically just vibrations in the air. When you strum the string of a guitar, just like if you hit a rubber band, it vibrates and those vibrations travel through the air until they reach you as sound.

Tightening the string with the tuning knobs changes how easily a string can vibrate when you hit it, and so does pressing your finger into the string at certain points. Strings of different thicknesses will also vibrate differently.

The frets themselves don’t really have much to do with it, those are mostly just to mark where to press on the string to get it vibrate a certain way.

Depending on where you hold down a guitar string (on which fret), it is able to oscillate back and forth at a certain speed. The rate that it oscillates is the note that it is playing.

Different guitar strings have a different thickness. The thickness contributes to how much it will oscillate. Think of how after a certain thickness, you would eventually have a rod that won’t wiggle at all.

In very broad terms, the pitch a vibrating string makes when it is held motionless on both ends depends on :-

a) the length of the vibrating part of the string – the longer the length the lower the pitch

b) the tension on the string – the more tension, the higher the pitch

c) the construction of the string – ie the type of material and how it is made. Generally speaking the “heavier” the string, the lower the pitch.

The frets on a guitar are used to help guide the player to make the correct pitch changes from note to note. For most music, the players want the pitch to go from ‘note to note’ accurately rather than say, something in between a C and C sharp etc. So the frets allow this to happen more easily, as compared to a fretless guitar or violin where the position of the finger must be very accurate in order to get the notes accurate.

Of course, some people bend notes and want other sound effects but that is another story altogether.

Sound is (essentially) vibrations in the air. The pitch produced by a string instrument, be it a guitar or a rubber band, is determined by the speed at which the string vibrates, which causes vibrations in the air. This is impacted by length of the vibrating portion of the string, and how taught the string is. When you stretch a rubber band you change it’s pitch, and when you press down on a guitar string you do the same thing. When you press down on a guitar string you change the length of the vibrating portion, changing the speed at which it vibrates, changing the pitch.

In music you are generally trying to play specific pitches, which require the string to vibrate at particular speed, which requires pressing down the string in a particular location. If you are in the wrong location you will play the wrong note. On a guitar the frets, the bits of metal on the neck, are in (approximately) the proper spot for each fret to result in the desired frequency being played. You press down the string and the string makes contact with the fret, and the fret is what determines how long the vibrating portion is, which makes playing much easier. There are a number of string instruments without frets, such as violins, violas, cellos, and even fretless basses and guitars. On a fretless instrument like a violin playing the right notes requires you to be very precise; if you miss the spot by just the slightest amount the note you play will be very slightly wrong. However on a fretted instrument, because the string is actually cut off at the fret, being in the very slightly wrong spot doesn’t result in a wrong note.

TL;DR: Frets make it much easier to play the right note, requiring less precision than instruments like a violin or a cello.

The pitch of an open string, not pressed down at any fret, is determined by

1 the length of the string, from bridge to nut, along with

2 the thickness of the string, along with

3 the amount of tension applied to tighten the string by the tuning gears at the head.

This pitch can be further modified by pressing strings down between the frets.