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.
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.

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'

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 |
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.
Greg Byers- http://www.byersguitars.com
Scott Richter- http://www.richterguitars.com
Peter Oberg- http://www.obergguitars.com
Waylin Carpenter- http://www.waylincarpenter.com