After watching Doug Proper’s Looth Group video describing a fast and innovative method for computing saddle compensation (which Doug worked out using the Pythagorean theorem) and his related method for cutting a 3 degree saddle slot, Michael was inspired to draft a short primer on intonation, and incorporate Doug’s method into an easy to use spreadsheet.  The two collaborated and the attached document and spreadsheet are the result.

The document provides the basics of why and how we compensate the saddle position on steel string guitars, and the spreadsheet will do the compensation calculation for a particular guitar, using the scale length and string height above the 12^th fret as the input variables.  Looth Group members are encouraged to watch the archived version of Doug’s video for more information about the development of the method, why and how it works, and how best to cut a 3 degree saddle slot.

The key facts about the compensation calculation using the spreadsheet are: (1) the calculation assumes you are using a 3 degree saddle slot; and (2) the result gives you the location of the string breakpoint where the 3 degree saddle slot intersects the first string (high E).  To use the spreadsheet simply input the scale length and string height (of the first string) at the 12^th fret in the yellow colored cells in the top portion of the spreadsheet.  The result (the “aft” offset comprising the necessary compensation amount at the high E breakpoint) is displayed in the orange cell.

To use the individual string compensation calculator at the bottom of the spreadsheet, tune the individual string to pitch, and play the octave at the 12^th fret, noting the error in cents.  Enter the values for the length of the first fret and the cents error in the yellow boxes, and adjust (sharp means adjust aft, flat means forward) the particular string’s breakpoint based on the result in the orange box.  The individual string compensation calculator works regardless of the angle of the saddle slot.

Michael Minton, M Squared Guitars (Pensacola FL)

Doug Proper, Guitar Specialist, Inc. (Bedford Hills, NY)