Intonation

Intonation
by Adam Moore - Guitar Tech for KSM Gutiars

Most people do not even know what intonation is or how it effects the playability of a guitar/fretted instrument. On every fretted instrument ever made there are two spots where there are breaking points. One breaking point is at the top of the instrument with a part called the "nut" (part on the instrument where the string rests in grooves) the other breaking point is at the bottom of the instrument  with a part called the "bridge" (part on the instrument where the string rests in saddles). Usually, the bridge has an adjustable action where the strings can be raised or lowered and the intonation can can be adjusted.

The intonation is usually adjusted by turning a screw located in various places depending upon the model. The Foundation™ Bass Bridge allows for intonation adjustments by turning the intonation screws located parallel to the base of the bridge beneath the saddles. The Foundation™ Bass Bridge utilizes a patented design to lock in these adjustments once they have been made preventing any part from vibrating loose after extended use.


Intonation is an instruments true pitch, say for example that you tuned your instrument to exactly the note it is supposed to be and you move up the neck and hit another note and but the note you moved up to was a little flat or sharp this would mean that the your intonation is off. The best way to adjust your intonation is to buy a an electronic tuner and then tune the the open note to precisely the correct pitch. Once you have tuned the open note, hit its octave note on the twelfth (12th) fret and if the octave note is flat then that means the  length of the string needs to be shortened and that is done by moving the saddle toward the top of the instrument (toward the nut or tuning keys). If the octave note reads sharp, then the you would adjust the intonation in by doing the opposite and moving the saddle toward the bottom of the instrument (toward the rear of the bridge). The reason I use the twelfth (12th) fret to adjust the intonation is because it is exactly half the length of the string. This helps because I can get the full range of notes, and I know right away if the intonation is off since a pitch exactly one octave above my original pitch should be, when tuned properly, exactly twice the frequency as the original note. Also, it is important to make sure that you have a chromatic tuner because a standard guitar or bass tuner will not work since they only focus on the standard pitches fro the open notes on a guitar or bass. I recommend using a "strobe tuner" when making intonation adjustment since they are the most accurate tuners on the market however they are more expensive tuners.