True temperament
True temperament is a 12-tone tuning. It was invented by Anders Thidell. It is intended for use with the guitar, though there is no theoretical reason why it couldn't be used for other instruments.
Being a modified version of 12edo, it is a contemporary example of a well temperament.
Being based on field measurements of instruments, rather than on mathematical calculations, it is an example of an empirical tuning. (See list of approaches to musical tuning).
Tuning description
True Temperament chromatic tuning offsets
E= -2 • F= 0 • F#= -4 • G= +4 • G#= -4 • A= 0 • Bb= -4 • B= -1 • C= +2 • C#=-4 • D= +2 • Eb= -4.
True Temperament open string tuning offsets
6-string
1st E4= -1 • 2nd B3= -1 • 3rd G3= +4 • 4th D3= +2 • 5th A2= 0 • 6th E2 =-2
7-string
1st E4= -1 • 2nd B3= -1• 3rd G3= +4 • 4th D3= +2 • 5th A2 = 0 • 6th E2= -2 • 7th B1= -4
8-string
1st E4= -1 • 2nd B3= -1 • 3rd G3= +4 • 4th D3= +2 • 5th A2 = 0 • 6th E2= -2 • 7th B1= -4 • 8th F#1= -8
Scala file
! truetempA.scl Chromatic true temperament in the key of A 12 ! 96. 199. 302. 396. 502. 596. 698. 800. 896. 1004. 1096. 1200.
Physical tuning instructions
The web page The complete guide of tuning a true temperament guitar provides step by step instructions for tuning a physical instrument.
The page begins: "Start with setting the exact scale length by adjusting the distance between all bridge saddles and the nut at 648 mm (25,5″), if you have Fender, Ibanez, Schecter etc. Do the same procedure if you tune a guitar with Gibson scale: 628 mm (24,75″). Below you can see the tuning method that suits you the best..."
Real world usage
True temperament is one of few tuning systems which has instruments manufactured specifically for it on a corporate scale. True temperament guitars are manufactured by Caparison, Hill Guitar Company, Mayones, Strandberg, Sanden and several other manufacturers.