# Luthier

(Difference between revisions)
 Revision as of 17:00, 11 November 2009 (view source) (Created page with '== Inspiration == * FMIT tuner gives you a table of the distribution of tunings of all the notes you play. * Calibration of guitars are basically done by moving the bridge piece…')← Older edit Current revision as of 22:20, 21 April 2010 (view source)Trece8 (Talk | contribs) (→Formula of misplaced bridge pieces) Line 13: Line 13: == Formula of misplaced bridge pieces == == Formula of misplaced bridge pieces == - (Currently at work, but it will surely be an easy one) + [itex] + + x/l_0=(2^(-C_t/1200)-1)/(2^(t/12)-1) + + [/itex] + + Where x is the distance to shorten the string (move the bridge saddle towards the headstock), l_0 is the open string distance from the initial bridge saddle up to the nut ; t is the fret number ; and C_t is the amount of cents it is off in the Tth fret.

## Inspiration

• FMIT tuner gives you a table of the distribution of tunings of all the notes you play.
• Calibration of guitars are basically done by moving the bridge pieces

## Method

• By the same method as FMIT measures tuning and distribution of tuning per note, playing notes in just one string you measure the de-tuning of each note there.
• Making a simple string model, we fit the distributions of tunings to the behaviour it would be for the string to be shorten (but frets in the same place)
• We give the distance to move the bridge piece in mm to have most of the notes played in tune.
• We repeat the process, for further precission.

## Formula of misplaced bridge pieces

[itex]

x/l_0=(2^(-C_t/1200)-1)/(2^(t/12)-1)

[/itex]

Where x is the distance to shorten the string (move the bridge saddle towards the headstock), l_0 is the open string distance from the initial bridge saddle up to the nut ; t is the fret number ; and C_t is the amount of cents it is off in the Tth fret.