Circular Tuned Harmonicas


Article By : Robert Coble
Used by Permission

The standard Richter-tuned diatonic harmonica in key "C" is layed out as follows:

Hole 1 2 3 4 5 6 7 8 9 10
Blow C E G C E G C E G C
Draw D G B D F A B D F A

The standard Richter-tuned diatonic harmonica in key "G" is layed out as follows:

Hole 1 2 3 4 5 6 7 8 9 10
Blow G B D G B D G B D G
Draw A D F# A C E F# A C E

I'm going to use a "G" key harmonica for Circular tuning, because that's all I have. It doesn't really matter; the principle remains the same no matter what key is used.

The Circular-tuned diatonic harmonica in key "G" is layed out as follows:

Hole 1 2 3 4 5 6 7 8 9 10
Blow G B D F A C E G B D
Draw A C E G B D F A C E

Hmmm, no F#, which is the 7th scale degree in key "G". So, what IS this Circular-tuning related to

The Circular-tuned harps are tuned in the Mixolydian mode, instead of the (standard) Ionian mode.

A-R-R-G-H! MOM, he's using that nasty music theory stuff!

A small digression: Ionian mode is composed of exactly the same notes as the major scale. For reference, here are the "C" major scale (Ionian mode) notes:

Note: C D E F G A B C
Scale Degree: 1 2 3 4 5 6 7 8

The "G" Mixolydian mode notes are exactly the same notes, except that the Mixolydian mode ("G") starts on the 5th scale degree of the corresponding Ionian mode ("C"):

Note: G A B C D E F G
Scale Degree: 1 2 3 4 5 6 7 8

(And there are 5 other modes, and a bunch of other stuff, but I'm NOT going there tonight!)

The nice thing about this tuning is that Circular tuning provides complete diatonic chords (triads) for all chords in the Ionian mode, in addition to ALL diatonic notes for that Ionian mode!

The diatonic chords for "C" major scale (Ionian mode) and the corresponding chords on the "G" Circular-tuned harp are:


I----C-E-G (major chord) (Holes 2-3-4 draw; 6-7-8 blow)
ii---D-F-A (minor chord) (Holes 3-4-5 blow; 6-7-8 draw)
iii--E-G-B (minor chord) (Holes 3-4-5 draw; 7-8-9 blow)
IV---F-A-C (major chord) (Holes 4-5-6 blow; 7-8-9 draw)
V----G-B-D (major chord) (Holes 1-2-3 blow; 4-5-6 draw; 8-9-10 blow)
vi---A-C-E (minor chord) (Holes 1-2-3 draw; 5-6-7 blow; 8-9-10 draw)
vii`-B-D-F (diminished chord) (Holes 2-3-4 blow; 5-6-7 draw)

If you lay out these chords on the two different tunings, you'll find that you only get a few of the full chords (triads) on the Richter-tuned harp (regardless of the position), whereas you get all of the chords at least TWICE for the Ionian mode on the Circular-tuned harp. Consequently, you have a much richer palette for chording.

An additional bonus is that ALL notes of ALL 7 modes occur without bending. This makes playing tradiional mountain music much easier. That makes playing in the natural minor (Aeolian mode) much easier. You can use draw bends on every hole; there are no blow bends. (I presume that overblowing can be one, but I have no experience with that on a Circular-tuned harp.)

There is no low-high note reversal at hole 7. Every blow note is one diatonic step below the corresponding draw note.

I haven't tried playing the blues, using a lot of b3, b5, b7 notes, but they are there, if you bend. I intend to use this tuning more for bluegrass/gospel/traditional than for anything else. I already love the chording for accompaniment. I also love having all the notes for playing melodies, without bends. It's not that I can't bend; it's that the intonation of bent notes is not the same (IMHO) as the unbent notes. Bending works to advantage for the blues, but "curdles the cow's cream" (so to speak) for traditional music

I know I've probably overlooked several important points, but others on this list are much more qualified to fill in the gaps. This should be enough to get you started.

Crazy ('bout harp!) Bob

Thanks again Bob for helping out those of us just know how to blow, but don't understand much about music theory

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