The Raga Guitar Extended 7-string | 14 Note Octave Just Guitar | Extended 7-sting (short Scale)

L to R: Extended 7-string | Fourteen Note Octave Just Guitar |
Extended 7-string (short scale)

25-String Raga Guitar

The Raga Guitar was built by luthier Scott Richter.

This instrument is a hybrid of Matt's extended 7-string guitar and a sarod. It has seven playing strings, twelve sympathetic strings (steel strings), four jawari, and two chikari for a total of twenty-five strings. The first string has 24 frets, the seventh string has two extra frets past the nut (730 mm scale length), and the fingerboard is in just intonation (purely tuned intervals).

Note Name Ratio Cents
E 1/1 0
F 135/128 92
F# 9/8 204
G 6/5 316
G# 5/4 386
A 4/3 498
A# 45/32 590
B 3/2 702
C 8/5 814
C# 5/3 884
D 16/9 996
D# 15/8 1088

Watch Matt talk about the Raga Guitar in this video clip:

low quality | high quality .mov

Click the picture at left for a high resolution view of the Raga Guitar.

Extended 7-string Guitar

The Extended 7-String guitar was built by luthier Gregory Byers (of Willets, CA). The guitar has extra low and high frets, adding an octave to its range.

Extra frets at the nut

The 7th string has two extra frets past the nut, (729.6mm scale length) allowing the guitar to reach a low 'A' or 'G' (beneath the low 'E' string). With the sliding capo system, it is possible to stop the string chromatically within the first five frets. There are three extra high frets on the first string, reaching 22 frets, or a high 'D'

Fourteen-Note Octave Just Guitar

Watch Matt perform Settings In A Utopian World on the 14-Note Octave Just guitar.

This 6-string guitar was built by Greg Byers of Willits California in 1994. The fingerboard was modified by Scott Richter of Fairfax California during the early part of 2010. The fingerboard is set to a 7-limit just intonation system. The 6 strings are tuned like a standard guitar (in one sense) and the fundamental note is E. I have two shades of G (minor 3rd), and two shades of D (minor 7th). Here are the ratios:

Note Ratio Cents Just Intonation Term mm
E 1/1 0    
F 16/15 112 large just minor second 40.72
F# 9/8 204 large just major second 72.25
G 7/6 267 septimal minor third 92.9
G 6/5 316 just minor third 108.45
G# 5/4 386 just major third 129.9
A 4/3 498 just perfect fourth 162.48
A# 45/32 590 high 5-limit tritone 187.72
B 3/2 702 just fifth 216.68
C 8/5 814 just minor sixth 243.82
C# 5/3 884 just major sixth 259.92
D 7/4 969 septimal minor seventh 278.6
D 9/5 1018 five-limit large minor seventh 288.97
D# 15/8 1088 five-limit major seventh 303.27


Extended 7-string Guitar (Short Scale)

This instrument was built by Waylin Carpenter of Sacramento California in 2009. It has all the features of the Byers extended 7-string but has a 615mm scale length across the first 6-strings. The string spacing at the nut is set at 48mm. In addition to the string spacing at the saddle of 67mm, the spacing is not even across all the strings. The string spacing between strings (1,2) (2,3) and (3,4) are set at 12mm between each pair of strings. The string spacing between strings (4,5) (5,6) and (6,7) are set at 10.33mm between each pair of strings. The sound box was not modified in the construction of this instrument. It has amazing playability, sweetness, and strength of projection of sound.

7-String Luthiers

Greg Byers-
Scott Richter-
Peter Oberg-
Waylin Carpenter-