Fretting Formula!

[Stradivarius]

I am wondering how many have heard of Stradivarius's harmonic formula for figuring out fret spacings for any scale you desire?

The number is 5.612568731829 %

Let's say you want to fret a 36 inch bass scale. 5.612568731829 % of 36" is your first fret spacing then you deduct 5.612568731829 % off from then on to make as many frets as you want. This formula is perfect and will make perfect fret spacings.

[Woodenspoke]

I didnt know violins used frets?

[Narcissism]

True, Stradivarius did make violins, but due to the profession, and demand, it was more economically efficient to be capable of building several different instruments.

Stradivarius did make a few guitars.

[soapbarstrat]

damn, thought someone was going to step up to the plate and breast feed frets

[WezV]

sod the formula, i wanna see the tools he was using to cut slots that accurately

[borge]

I am wondering how many have heard of Stradivarius's harmonic formula for figuring out fret spacings for any scale you desire?

The number is 5.612568731829 %

Let's say you want to fret a 36 inch bass scale. 5.612568731829 % of 36" is your first fret spacing then you deduct 5.612568731829 % off from then on to make as many frets as you want. This formula is perfect and will make perfect fret spacings.

1/.05612568731829 = 17.817153745111008!

Dividing by 17.817 is the accepted standard......

IE you're doing what everyone else is

[WezV]

i decided to check my spreadsheet to quickly check this number out, it looked familiar and i was not surprised when the numbers came out just as you would expect - just a different way of doing the sums

no difference at 3dp - that 1/1000", fairly hard to cut and have wood stay that accurate

slight differences at 14dp, but i assume thats mainly because i used scale length/17.817 for the normal fret positions, rather than the full long number

edit: what borge said

[Prostheta]

Hey Wez - I think it would be appropriate to create an Excel sheet which factors in string deflection a la the "Gibson scale of wonky". ;-)

Ohwait. Wrong topic. Perhaps Mr Berty Strad had customers with an ultra-light touch and a hankering for long scale instruments with pyramid frets.

Edited May 21, 2010 by Prostheta

[WezV]

you do that when you have time... all i have is a spreadsheet that lets me change formulae pretty quickly for these (less than) random numbers people keep suggesting for fret spacing...... and i still see no reason to go for anything but 17.817 - especially when i allready have (and will soon get another) frets scale template that makes guitars that tune as people expect them to and works well.

i am all open for another magic number thoughl

[Prostheta]

True. Many refinements are cases of diminishing returns, with very few people taking any advantage of them.

[KeithHowell]

All the "magic" numbers are calculated, or should be, from the twelfth route of 2 anyway. So if you do your mathematics correctly with this fundamental principle you will get the correct spacings.

Keith

[Stradivarius]

Wow guys!!

So no one ever heard of it?

Thats amazing.

I have never used anything but that formula.

[WezV]

????

its he same one 99.9% of us use - just written differently. i think i have seen it written that why before which is why the number was familiar, but have always chosen to go with the way its written down in in most of the books and guides available for such things

[borge]

Wow guys!!

So no one ever heard of it?

Thats amazing.

I have never used anything but that formula.

You remind me of an ex-girlfriend of mine; only hears her own voice, her eyes would glaze over as others spoke, whilst she impatiently waited for her turn to speak again.

I am wondering how many have heard of Stradivarius's harmonic formula for figuring out fret spacings for any scale you desire?

The number is 5.612568731829 %

Let's say you want to fret a 36 inch bass scale. 5.612568731829 % of 36" is your first fret spacing then you deduct 5.612568731829 % off from then on to make as many frets as you want. This formula is perfect and will make perfect fret spacings.

1/.05612568731829 = 17.817153745111008!

Dividing by 17.817 is the accepted standard......

IE you're doing what everyone else is

You are reaching answers identical to everyone else with a different calculation.

[KeithHowell]

You are reaching answers identical to everyone else with a different calculation.

It is not even a different calculation! It is the same one just expressed differently.

The mathematics is as follows:

Scale Length (SL) / 2^1/12 = Fret to bridge distance (F2B)

The Twelfth Root of 2 is 1.0594630943 to 10 decimal places

Therefore SL/1.0594630943 = F2B

or SL * 0.943874312 = F2B (taking the inverse of twelfth root)

therefore SL *(1 - 0.943874312) = Fret Distance(FD)

or SL * 0.05612256 = FD

or SL /17.81715374 =FD (Taking the inverse of 0.05612256)

Which is the same as SL * 5.612256/100 = FD if you want to express it in terms of a percentage.

So yes we have all used it.

Keith

Edited May 27, 2010 by KeithHowell