Fanned Fret Accuracy

[AirGuitarist]

Hi,

 

I lost a Nut  I'd made for a Custom Fanned Fret guitar I've built and have to make a new one.

 

This got me to thinking . and has raised a few doubts in my mind about the benefits of Fanned Frets....

My main concern is that as string separation tapers from Bridge to Nut due to the smaller Nut width / larger bridge width, this means that on a conventional fret board the string angle of the outer strings will cause the intersection of the fret and string to not accurately match the correct fret spacing as the string is angled across the frets rather than perpendicular to them.  However the difference looks to be  so small as to be insignificant - in the 0.01 mm ball-park.

On a Fanned Fret Guitar on the other-hand, I assume that the two different scales are measured along the outer strings with the frets slots cut between these two points for each fret position. In this case the centre line will be inaccurately fretted and the outer strings correctly fretted.

I'm concerned that because the frets are angled on a fanned fret guitar, that these small differences that affect the inner strings will exaggerate the difference between ideal and actual fret/string intersection.

 

Would this be a problem?

[curtisa]

While it would be true that the tapering of the string from bridge to nut would cause a pitch error on the fretted note the more acute the taper is, this pitch error is minute and is also partially compensated by the adjustability of the saddles when setting the intonation.

I guess you could argue that a "true" single scale length guitar would have mildly semi-circular shaped frets and nut, where the centre of each frets' arc would be the convergence point of all six strings as they taper beyond the limits of the nut. In practicality almost no-one's ears can hear such a small error when compared to the inherent innacurate nature of steel strings pressed against metal frets. You'd get more pitch error by exerting excessive fret-hand pressure while fretting, micro-bending each note by mashing it down hard behind the fret.

Fan fretting/multiscaling doesn't change any of this. The only difference is that each string gets it's own unique scale length rather than a single common scale length for all strings.

[ScottR]

Having never played one, that conversation brings up another question to me. Depending on where you are on the fretboard bending a note would seem to react differently pushing the string or pulling it, since in one direction direction the fret gets closer to the saddle, or at least is not as far away from the saddle as the other direction.

On the other hand that must not be too difficult to overcome, judging from the number of these being produced and played.

SR

[verhoevenc]

Take a look at the true temperament frets. Apparently that's what truly accurate frets should look like to be perfect at each fret, for each string, etc. Straight frets, fanned frets, we're all playing with errors here.

Chris

[curtisa]

11 hours ago, ScottR said:

Having never played one, that conversation brings up another question to me. Depending on where you are on the fretboard bending a note would seem to react differently pushing the string or pulling it, since in one direction direction the fret gets closer to the saddle, or at least is not as far away from the saddle as the other direction.

On the other hand that must not be too difficult to overcome, judging from the number of these being produced and played.

I think you'd be surprised how little adaption is required to switch from straight to angled frets. You might even find that it encourages a more relaxed fretting wrist when playing and shifting from lower to upper registers. When changing positions from the lower areas of the neck (further from the body) to the higher areas (closer to the body), the natural tendency of the wrist is to want to angle the fingers more horizontally as it moves closer to the body. This coincides with the changing angle of the frets as they travel up the neck, which should (theoretically at least) match more closely how the wrist wants to turn as the hand is brought closer to the body.

A good example is fretting a full barre Fmaj chord on the first fret and then playing the exact same chord on the 13th.  The lower barre chord forces the wrist to rotate clockwise in order to fret all the notes properly, and the same chord played higher forces the wrist to rotate counterclockwise for the same result. If the frets are all angled to naturally counteract this rotation, the wrist should adopt a more relaxed angle between the two extremes.

Bending strings is no different. The "relaxed" direction your fingers want to push or pull the string to bend it should be the same direction the fret angle.

There's no free lunch though. It is possible to over-compensate things. Multiscales with really wide fan ranges (extremely steep-angled frets at each end of the fretboard) will probably negate these ergonomic benefits. And if you're used to sighting your hands' position on the fretboard by looking at the fret dots/side dots you may find that hitting the highest notes by what visually looks right takes some getting used to, as the increasing negative fret angle on the higher frets can skew your alignment of the fret dot vs where you think your fingers have landed.

[curtisa]

35 minutes ago, verhoevenc said:

Take a look at the true temperament frets. Apparently that's what truly accurate frets should look like to be perfect at each fret, for each string, etc. Straight frets, fanned frets, we're all playing with errors here.

True Temperament frets only ensure that the guitar plays as close as practicable to Equal Temperament rather than each note being mathematically perfect (a physical impossibility on a guitar, or indeed any instrument where the notes are primarily developed by fixed means - piano, organ, harp etc). Even then, the TT fretted instrument will still have the same inherent pitch errors already present within the Equal Temperament system, something that cannot be avoided in western music.

I've seen many people say that bending strings on a TT guitar must feel weird, or require a different playing style. But the counter-argument by people who have tried it always appears to be that it feels no different...or perhaps they just adapt quickly?

[verhoevenc]

I built a body for a guy that slapped one of their necks on it. Didn't feel too odd for the few minutes I played it. 

Chris