written 1998-4-9, revised 1998-10-29

The "Jimi Hendrix Chord" (Dominant 7th, sharp 9th)
in 19-Limit just-intonation.

(you're listening to one excerpt of it)

This piece is a virtuoso étude for the regular 12-EQ Guitar. The major challenge is the finger independence needed to fret a chord and bend each of the four fingered strings separately by the proper amount to acheive a particular just-intonation chord.

It was inspired by a debate I had with Paul Erlich (via the Tuning Forum) over which ratios would most likely be implied by the "sharp 9th" [2^(3/12) = 3.00 semitones] of the 12-EQ chord Jimi played, and with which each phrase of my piece begins.

I had originally made a statement that Jimi Hendrix deserves the credit for bringing 19/16 [19¹ = 2.98 semitones] decisively into the harmonic language of rock. Erlich pointed out that, because Jimi played the chord on guitar with the regular 12-EQ frets, I had neglected to take into account the fact that the "7th" of the 12-EQ chord [2^(10/12) = 10.00 semitones] was 31 cents too sharp to represent 7/4 [7¹ = 9.69 semitones]. He suggested that if Jimi bent the two lowest notes (played with the stronger fingers) upward, the best rational interpretation that could be given to the top two 12-EQ notes (played by the weaker fingers, and with no bending) would be to call them a 7/4 and a 7/6 [3^-1 7¹ = 2.67 semitones], his main point being that the interval between the top two notes in 12-EQ, a "perfect 4th" [2^(5/12) = 5.00 semitones], was only 2 cents larger than the interval between 7/4 and 7/6: a 4/3 [= 4.98 semitones].

Interestingly, though, 19/16 [= 2.98 semitones] is only 2 cents smaller than the interval between the original bass note (before bending) and the 12-EQ "sharp 9th" [2^(3/12) = 3.00 semitones]. Thus, while I basically came to agree with Erlich's suggestion, it seemed possible to me that a lingering memory of the original bass note may partially force one to hear the "sharp 9th" as being able to represent 19/16. Also, I feel that the 19/16 has a funkier, bluesier sound than 7/6, and I like it. Thus, the idea for this piece.

(For those interested in reading the entire discussion, it can be found here on Drew Skyfyre's site. It's quite long.)

Here's the excerpt the page opened with. This is a graph of the pitches used in the chord progression which cycles around each time: