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How to make a Kite Guitar: Difference between revisions

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One way to get an 8-string acoustic is to convert a 12-string guitar. The neck will be sufficiently strong and there will be enough tuners. There's fewer strings but more courses, so the new fretboard may need to be wider than the old one. The fretboard overhang can be filled with bondo to create a nice-feeling neck. Another possibility is to convert a 6-string classical nylon-string to 7 or 8 strings. The fingerboard is wide enough that it may suffice as is. The tension is low enough that an extra string or two won't break the guitar. The 3 holes on each side of the headstock that the tuner pegs go through can be filled and 4 new holes drilled.
One way to get an 8-string acoustic is to convert a 12-string guitar. The neck will be sufficiently strong and there will be enough tuners. There's fewer strings but more courses, so the new fretboard may need to be wider than the old one. The fretboard overhang can be filled with bondo to create a nice-feeling neck. Another possibility is to convert a 6-string classical nylon-string to 7 or 8 strings. The fingerboard is wide enough that it may suffice as is. The tension is low enough that an extra string or two won't break the guitar. The 3 holes on each side of the headstock that the tuner pegs go through can be filled and 4 new holes drilled.


In any given key, the Kite guitar has multiple "rainbow zones" on the neck. Assuming the tonic falls in the "sweet spot" between the 4th and 11th fret, it takes about 28 frets to provide 2 zones in every key, but it takes the full 41 frets to provide 3 zones. This 3rd zone increases the range the lead guitarist has to solo in by a 5th or so. The highest frets are very tight, but still playable melodically. Chording is very difficult.
In any given key, the Kite guitar has multiple "rainbow zones" on the neck. Assuming the tonic falls in the "sweet spot" between the 4th and 11th fret, it takes about 28 frets to provide 2 zones in every key, but it takes the full 41 frets to provide 3 zones. This 3rd zone increases the range the lead guitarist has to solo in by a 5th or so. The highest frets are very tight, but still playable melodically. Chording is very difficult. Having a 41st fret makes intonating the guitar easier, see below.


The fret spacing is 1.7 times tighter than a 12-edo guitar. This chart compares it to the standard fret spacing. The spacing between the nut and the first fret is about the same as the space between the 12-edo 9th and 10th frets. Increasing the overall scale length will widen the spacing.
The fret spacing is 1.7 times tighter than a 12-edo guitar. This chart compares it to the standard fret spacing. The spacing between the nut and the first fret is about the same as the space between the 12-edo 9th and 10th frets. Increasing the overall scale length will widen the spacing.
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== Saddle and Nut Compensation ==
== Saddle and Nut Compensation ==


Checking the intonation and compensation is similar to standard 12edo guitars but some of the fret comparisons are unavailable. The best comparisons to use for the Kite Guitar are described in the following chart.
'''Method #1:''' To find the saddle compensation on a standard guitar, one compares the harmonic at the 12th fret with the fretted note at the 12th fret. For the Kite guitar, by a weird coincidence, one does the same! But the 12th fret now makes the 3rd harmonic, not the 2nd. Thus the two notes should be an octave apart, not a unison. If using a tuner, this is not a problem. But if using your ear, a unison is easier to hear than an octave. To get a unison, when you fret the string, play the 2nd harmonic with your other hand. With your forefinger or middle finger, touch the string midway between the 32nd and 33rd frets. Then stretch your hand and pluck with your thumb as close as you can get to the midpoint between your finger and the bridge. If this isn't feasible (e.g. with a bass guitar), you can capo the string at the 12th fret and use both hands to play the harmonic. And to be extremely precise, the fretted note should be 0.48¢ sharper than the harmonic. The 3rd harmonic is 701.96¢ and the 41-edo interval is 702.44¢.
 
On a standard guitar, there's a formula for saddle compensation. Move the saddle point back by about 0.015" for every cent that the 12th fret note is sharp of the open string's 2nd harmonic. The 0.015" figure is more precisely the scale length times ln(2)/1200, which is roughly scaleLength/1731. Saddle compensation flattens the 12th fret note twice as much as the open string note. So if the 12th fret note is 3¢ sharp, flattening the open string note by 3¢ (about 0.045") flattens the 12th fret note by 6¢, and the <u>interval</u> between them is flattened by 3¢ to an exact octave.
 
On a Kite guitar, the scaleLength/1731 formula still holds. But saddle compensation affects the 12th fret note only one and a half times as much as the open string note. (Because an octave has [[frequency ratio]] 2/1 = twice as much, and a fifth has 3/2 = one and a half as much.)  Hence for each cent of sharpness, one must flatten by <u>two</u> cents.
 
For example, suppose the 12th fret note is 2¢ sharp of the 3rd harmonic. It's supposed to be 0.48¢ sharp, so the actual sharpness is only 1.5¢. (In practice, if one's tuner isn't this accurate, one might simply round down a bit.) Move the saddle point back by twice this, 3¢ or 0.045". This will flatten the open string by 3¢ and the 12th fret note by 4.5¢, narrowing the interval by 1.5¢ to an exact 41-edo 5th. On the saddle, mark a point 0.045" behind the exit point, and file up to the mark.
 
'''Alternative method #1:''' If the guitar has a 41st fret, compensation can be done more easily and accurately by comparing the harmonic at the 41st fret (the 4th harmonic) with the fretted note at the 41st fret. They should be an exact unison, so no need to subtract a half cent, and no need to play the harmonic of the fretted note. The 4th harmonic is a double octave, with frequency ratio 4/1, so saddle compensation affects the 41st fret note four times as much as the open string note. Hence for each cent of sharpness, one must flatten by <u>one-third</u> cent.
 
In the previous example, the 12th fret harmonic was 2¢ sharper than the fretted note. This would make the 41st fret note 9¢ sharp of the 4th harmonic. Move the saddle point back by 1/3 this, 3¢ or 0.045". This will flatten the open string by 3¢ and the 41st fret note by 12¢, narrowing the interval by 9¢ to an exact double octave.
 
This method is more accurate because tuners aren't perfect, and an error affects the compensation distance only one-sixth as much.
 
The following chart describes various fret comparisons.


* fret = the Kite Guitar fret number
* fret = the Kite Guitar fret number
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|}
|}


==== Further discussion and description of intonation compensation steps: ====
'''Method #1:''' To find the saddle compensation on a standard guitar, one compares the harmonic at the 12th fret with the fretted note at the 12th fret. For the Kite guitar, by a weird coincidence, one does the same! But the 12th fret now makes the 3rd harmonic, not the 2nd. Thus the two notes should be an octave apart, not a unison. If using a tuner, this is not a problem. But if using your ear, a unison is easier to hear than an octave. To get a unison, when you fret the string, play the 2nd harmonic with your other hand. With your forefinger or middle finger, touch the string midway between the 32nd and 33rd frets. Then stretch your hand and pluck with your thumb as close as you can get to the midpoint between your finger and the bridge. If this isn't feasible (e.g. with a bass guitar), you can capo the string at the 12th fret and use both hands to play the harmonic. And to be extremely precise, the fretted note should be 0.48¢ sharper than the harmonic. The 3rd harmonic is 701.96¢ and the 41-edo interval is 702.44¢.
On a standard guitar, there's a formula for saddle compensation. Move the saddle point back by about 0.015" for every cent that the 12th fret note is sharp of the open string's 2nd harmonic. The 0.015" figure is more precisely the scale length times ln(2)/1200, which is scaleLength/1731. Saddle compensation flattens the 12th fret note twice as much as the open string note. So if the 12th fret note is 3¢ sharp, flattening the open string note by 3¢ (about 0.045") flattens the 12th fret note by 6¢, and the <u>interval</u> between them is flattened by 3¢ to an exact octave.
On a Kite guitar, the scaleLength/1731 formula still holds. But saddle compensation affects the 12th fret note only one and a half times as much as the open string note. (Because an octave is 2/1 and a fifth is 3/2.)  Hence for each cent of sharpness, one must flatten by <u>two</u> cents. For example, suppose the 12th fret note is 2¢ sharp of the 3rd harmonic. It's supposed to be 0.48¢ sharp, so the actual sharpness is only 1.5¢. (In practice, if one's tuner isn't this accurate, one might simply round down a bit.) Move the saddle point back by twice this, 3¢ or 0.045". This will flatten the open string by 3¢ and the 12th fret note by 4.5¢, narrowing the interval by 1.5¢ to an exact 41-edo 5th. On the saddle, mark a point 0.045" behind the exit point, and file up to the mark.


'''Method #2:''' The first method serves as a rough check of the saddle points. But it's much safer to check multiple frets. The cents table below (printable pdf [http://tallkite.com/KiteGuitar/KiteGuitarNotes.pdf here]) has the pitch of every single note on the fretboard. The 2nd page of the pdf omits some redundant information to make room to pencil in discrepancies in cents. But the open strings aren't reliable, because the nut is not yet compensated (nut compensation must be done after saddle compensation). Use a capo to remove the nut issue. Capo the string at the 1st fret (or 2nd or 3rd, if the capo doesn't fit your 8-string very well). Tune the capo'ed string to the table, then compare the other frets to the table. <u>Important</u>: do not remove the capo during this process, as that will change the tension, and thus the pitch. It's usually sufficient to check every 4th fret, i.e. every dot. Look for the general trend. If the saddle point is too far back, the higher frets will be increasingly flat. Too far forward, and they will trend sharp. If there's an outlier that breaks the pattern, check its neighboring frets. No guitar is perfect. If some frets are sharp and some equally flat, that's the best you can get. Once you find the trend, estimate how much cents error would be expected at the 5th dot, which is almost an octave. That's roughly how many cents to compensate by. (To be super-precise, you could increase the cents by about 3%, so that 6¢ becomes 6.2¢.) Compensate as in method #1 with the scaleLength/1731 formula.
'''Method #2:''' The first method serves as a rough check of the saddle points. But it's much safer to check multiple frets. The cents table below (printable pdf [http://tallkite.com/KiteGuitar/KiteGuitarNotes.pdf here]) has the pitch of every single note on the fretboard. The 2nd page of the pdf omits some redundant information to make room to pencil in discrepancies in cents. But the open strings aren't reliable, because the nut is not yet compensated (nut compensation must be done after saddle compensation). Use a capo to remove the nut issue. Capo the string at the 1st fret (or 2nd or 3rd, if the capo doesn't fit your 8-string very well). Tune the capo'ed string to the table, then compare the other frets to the table. <u>Important</u>: do not remove the capo during this process, as that will change the tension, and thus the pitch. It's usually sufficient to check every 4th fret, i.e. every dot. Look for the general trend. If the saddle point is too far back, the higher frets will be increasingly flat. Too far forward, and they will trend sharp. If there's an outlier that breaks the pattern, check its neighboring frets. No guitar is perfect. If some frets are sharp and some equally flat, that's the best you can get. Once you find the trend, estimate how much cents error would be expected at the 5th dot, which is almost an octave. That's roughly how many cents to compensate by. (To be super-precise, you could increase the cents by about 3%, so that 6¢ becomes 6.2¢.) Compensate as in method #1 with the scaleLength/1731 formula.
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The easiest way to get an 8-string acoustic guitar is to convert a 12-string guitar. This leads to a rather tight string spacing. The spacing can be slightly improved as follows:
The easiest way to get an 8-string acoustic guitar is to convert a 12-string guitar. This leads to a rather tight string spacing. The spacing can be slightly improved as follows:


Conventional wisdom holds that there are two ways to space the strings: center-to-center and edge-to-edge. For the right hand, the latter is better than the former, because otherwise it's harder to fit one's finger between the thicker strings. Edge-to-edge spacing ensures that the gap between strings is uniform.  
Conventional wisdom holds that there are two ways to space the strings: center-to-center and edge-to-edge. For the right hand, the latter is better than the former, because otherwise it's harder to fit one's finger between the thicker strings. Edge-to-edge spacing ensures that the gap between strings is uniform, and each string is equally easy to pluck.  
 
On the left hand, if the spacing is too tight, when one frets a string and plays the neighboring string either open or fretted further back, the finger can dampen the neighboring string. Thus the important gap is the gap between every other string. That is, when fretting the 2nd string, the important gap is between the inner edges of the 1st and 3rd string. When fretting the 3rd string, it's between the 2nd and 4th string. When fretting the 1st string, the gap is between the 1st and 2nd string, but if the 2nd string is more or less in the center of the 1st-to-3rd gap, the 1st-to-2nd gap will be sufficiently large.
 
Center-to-center spacing results in the thicker strings being more crowded and harder to fret cleanly. Edge-to-edge spacing results in the thinner strings being harder to fret. The ideal string spacing for the left hand makes a uniform gap between alternate strings, with this gap measured edge-to-edge not center-to-center. This spacing is called edge-to-next-edge. 


On the left hand, if the spacing is too tight, when one frets a string and plays the neighboring string either open or fretted further back, the finger can dampen the neighboring string. Thus the important gap here is the gap between every other string. That is, between the 1st and 3rd string, between the 2nd and 4th string, etc. Center-to-center spacing results in this gap being smaller than need be for the thicker strings. Edge-to-edge spacing results in the same for the thinner strings. The ideal string spacing for the left hand makes a uniform gap, with this gap measured edge-to-edge not center-to-center. This spacing is called edge-to-next-edge. (or center-to-edge?)
But specifying that this gap be uniform doesn't completely specify the spacing, because one could shift every other string sideways without changing these gaps. Ideally each string should be midway between the nearest edges of the two neighboring strings, i.e. the center-to-edge spacing should be constant. But this is impossible. For example, the distance from the center of the 2nd string to the nearest edge of the 3rd string must be less than the distance from the center of the 3rd string to the nearest edge of the 2nd string, because the 2nd string is thinner.


But specifying that this gap be uniform doesn't completely specify the spacing, because one could shift every other string sideways without changing these gaps. So we also require that the distance from the center of the 1st string to the nearest edge of the 2nd string be half the size of this gap. And likewise for the center of the thickest string and the nearest edge of the next-thickest string.
So we need an additional requirement. It is not yet clear which one is best. We might require that the distance from the center of the 2nd string to the nearest edge of the 1st string be half the size of this gap, i.e. the 2nd string is in the middle of the 1st-to-3rd gap. In general, none of the other inner strings will be centered like this.


In the next table, R1, R2, etc. is the radius of each string, and D is a constant roughly equal to 1/7th of the nut width.
In the next table, R1, R2, etc. is the radius of each string, and D is a constant roughly equal to 1/7th of the nut width. The value of D is not consistent from column to column.
{| class="wikitable"
{| class="wikitable"
|+distance from center of 1st string to center of Nth string
|+distance from center of 1st string to center of Nth string
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!edge-to-edge
!edge-to-edge
!edge-to-next-edge
!edge-to-next-edge
!center-to-edge
|-
|-
!2nd string
!2nd string
|D
|D
|D + R1 + R2
|D + R1 + R2
|D + R2
|D + R1
|D + R2
|-
|-
!3rd string
!3rd string
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|2D + R1 + 2R2 + R3
|2D + R1 + 2R2 + R3
|2D + R1 + R3
|2D + R1 + R3
|2D + R2 + R3
|-
|-
!4th string
!4th string
|3D
|3D
|3D + R1 + 2R2 + 2R3 + R4
|3D + R1 + 2R2 + 2R3 + R4
|3D + 2R2 + R4
|3D + R1 + R2 + R4
|3D + R2 + R3 + R4
|-
|-
!5th string
!5th string
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|4D + R1 + 2R2 + 2R3 + 2R4 + R5
|4D + R1 + 2R2 + 2R3 + 2R4 + R5
|4D + R1 + 2R3 + R5
|4D + R1 + 2R3 + R5
|4D + R2 + R3 + R4 + R5
|-
|-
!6th string
!6th string
|5D
|5D
|5D + R1 + 2R2 + 2R3 + 2R4 + 2R5 + R6
|5D + R1 + 2R2 + 2R3 + 2R4 + 2R5 + R6
|5D + 2R2 + 2R4 + R6
|5D + R1 + R2 + 2R4 + R6
|5D + R2 + R3 + R4 + R5 + R6
|-
|-
!7th string
!7th string
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|6D + R1 + 2R2 + 2R3 + 2R4 + 2R5 + 2R6 + R7
|6D + R1 + 2R2 + 2R3 + 2R4 + 2R5 + 2R6 + R7
|6D + R1 + 2R3 + 2R5 + R7
|6D + R1 + 2R3 + 2R5 + R7
|6D + R2 + R3 + R4 + R5 + R6 + R7
|-
|-
!8th string
!8th string
|7D
|7D
|7D + R1 + 2R2 + 2R3 + 2R4 + 2R5 + 2R6 + 2R7 + R8
|7D + R1 + 2R2 + 2R3 + 2R4 + 2R5 + 2R6 + 2R7 + R8
|7D + 2R2 + 2R4 + 2R6 + R8
|7D + R1 + R2 + 2R4 + 2R6 + R8
7D + R1 + 2R3 + 2R5 + 2R7
|7D + R2 + R3 + R4 + R5 + R6 + R7 + R8
|}
|}
Note that the nut is slotted edge-to-next-edge but the bridge is edge-to-edge, so as one plays further up the neck, the spacing deviates from the ideal. But the spacing widens further up the neck, making fretting cleanly easier, so this is not a problem.


== Tables ==
== Tables ==
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