Frequently asked question about True Temperament

Well, the easy answer to that question is that True Temperament™ Fretting System is a revolutionary new way to construct guitar fingerboards with Curved Frets™ which tune accurately along the whole neck. We call it Dynamic Intonation™. The Thidell Formula One temperament will give you a super-accurate intonation.  All the different keys that a guitarist uses works perfectly fine all over the fingerboard.

No, all keys work together perfectly fine all over the fretboard. The Thidell Formula One temperament is the only temperament we now offer and is not to be confused with other temperaments we have offered in the past, like Meantone and True Temperament 12 tone equal etc.

The answer to that is Yes! We currently have fret models for 6-, 7-, 8-string electric guitar, acoustic steel and nylon as well as for bass guitar. Also more advanced multiscale models and hybrid fanned fret/True Temperament.

There´s nothing wrong with straight frets per se, but if you want a close to perfect as possible intonated guitar you should of course go for the curved TT-frets!

Here´s an explanation for you: Standard equal tempered fret spacing is calculated from one single piece of information about the instrument – the scale length (the theoretical speaking length of the open strings). A divisor constant is used to determine the locations of the frets. The scale length divided by the constant gives the position of the first fret. The remaining length after subtracting the first fret, divided by the same constant, gives the position of the second fret, and so on.
The frequency of a vibrating string is determined by three factors: the speaking length, its mass, and the tension applied. All three of these factors are affected to varying degrees when a string is pressed down on a fret. Along the neck, the length and mass decrease by 50% per octave. Changing the length affects the stiffness. The tension is affected by fretting the string, as the string height is not zero. Pressing the string to the fret stretches the string slightly, increasing the tension and thus sharpening the notes produced.

The only way to fully compensate for all these parameters is to adjust each and every string-to-fret contact point on the fingerboard separately, until each and every note plays the target frequency exactly. This, which is impossible on a guitar with traditional, one-piece, straight frets, is exactly what we do with Dynamic Intonation™, and Curved Frets™.

Not at all. The playing feel on a True Temperament guitar is not different from any other standard guitar. 

No problem. Bending a string on a TT guitar does not differ from a guitar with straight frets. Please see Fredrik Pihls video below

No, not really. This is all about the intonation range at the bridge, for instance a Tune-o-matic bridge. A heavy string gauge combined with down tuning can end up out of intonation range.

Our steel-string acoustic fingerboards (650 mm and 630 mm scale) work fine with 0,011- to 0,013-set with a wound 3d string.

For our nylon-string acoustic fingerboard (650 mm scale) you can use medium to hard tension strings. We have through the years tested a big range of string brands and noticed that plain nylon strings varies a lot in tension consistensy. We can recommend Savarez Corum strings

To tune a TT-guitar is not complicated at all. But there are some important things you need to have clear. For instance tuning the open strings – except for the A string – to an ordinary chromatic tuner will not work with a True Temperament guitar, as the open strings are not tuned in equal tempered intervals.
The Thidell Formula One temperament is built around fret positions and tuning offsets. Each set of Curved Frets™ is designed to specifications derived from our exacting Dynamic Intonation™ fret position process.
NOTE! All tuning offsets starts from zero cent in the “equal” temperament.
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:
1st E4= -1 • 2nd B3= -1 • 3rd G3= +4 • 4th D3= +2 • 5th A2= 0 • 6th E2 =-2

1st E4= -1 • 2nd B3= -1• 3rd G3= +4 • 4th D3= +2 • 5th A2 = 0 • 6th E2= -2 • 7th B1= -4

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


Tuning the open strings – except for the A string – to an ordinary chromatic tuner will not work with a True Temperament guitar, as the open strings are not tuned in equal tempered intervals.

Non programmable tuners can be used to a certain point. For instance like this:

Tune  A on all strings: 5th fret on the low E-string.  A on the open 5th string and the 12th fret. 7th fret on the D-string. 2nd fret and 14th fret on the G-string. 10th fret on the B-string. 5th fret on the high E-string.
If all octaves sounds the same, your instrument is well intonated.

StroboPro – on line Strobe Tuner. FREE!
StroboPro is a free web based strobe tuner that includes the True Temperament tunings. Works on line on your computer,  on smart phone and Ipad, both in iOS and Android.
The TT-tuning is available for 6-, 7- and 8-string True Temperament guitars. Works both as open string and chromatic mode (for intonation). Highly recommended!
Link to StroboPro on line Strobe Tuner:

For use on stage, in the studio, and live playing in general, we recommend the programmable strobe tuner Sonic Research Turbo Tuner ST-300 stomp box. It comes with True Temperament as a preset. High precision +-0,02 cent. Works both as in open string and chromatic mode (for intonation). 

PST – Precision Strobe Tuner app, made in USA by James Campbell, includes the True Temperament tuning. This superb strobe tuner for iOS: iPhone and iPad, is available in the App store, at a low cost. We strongly recommend all iOS TT-players to download this very accurate guitar tuner!

How to navigate PST to the True Temperament mode:
Tap [Settings] and use [Next>] to navigate to the Note Tracking Mode page.
Tap [Guitar] and use [Next>] to navigate to User Bank 1.
Tap [>] to navigate to Fixed Bank 5 and the True Temperament mode.
Tap the [Enable Button] and then tap the [Done Button].
Ready to tune your TT guitar!
The TT page stays in the display, when you open the PST app next time.
More info: www.precisionstrobe.com

After 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″).  
You do it In exactly the same way you would intonate with a standard neck – by matching the Thidell Formula 1 open string notes to the octave (12th fret) notes.

Of course you can! A TT-equipped neck intonates superior to any straight fretted neck. You can tune down within sensible limits. The limitation on how low you can go before the intonation craps out depends on the string gauge. Thinner ones can become too floppy and difficult to intonate when tuned down.

It works just fine together with “ordinary” instruments. The offsets from Equal Temper are not so severe that they create any dissonance whatsoever.

True Temperament works very well with acoustic guitars; steelstringed as well as nylonstringed. Correcting intonation on an acoustic guitar is, as you know, very limited. If you want to assure yourself of an acoustic guitar that provides close to perfect intonation for every note across the fretboard you should go for the TT system.
  We offer the Thidell Formula 1 temperament for both steel-string (wound G) and nylon-string guitars with 650 mm and 630 mm scale length.

Yes! We offer the Thidell Formula 1 temperament for 6-, 7- and 8-string versions in 25,5” and 26,5″ scale length, and 8-string for 27″ scale.

Yes it is! We have following scales avaiable 4- and 5-string 34″ and 6 string 33″ scale electric bass.

Yes it´s possible to do a so called conversion which means replacing the fingerboard with a TT one, fret slot it and then fret it with TT-frets.
Can be done by a skilled luthier at your True Temperament Service point.