Getting Started with the Offset Modal System

See also:
The Real Parallel Galaxy
Emmett Chapman
December, 2004.

Parallel Galaxy
Joe McCollam
November 21, 2004.

Wheel Charts and Offset Modal System
Emmett Chapman
September 10, 2001.

A post by Steve Gajdos to on Nov. 13, 2010

    I know this may be a subject talked about to death but I still find some question for me that needs to be asked. Those of you who were there at Emmett's Interlochen Seminar class on this subject will know what I mean, so please chime in if you know the answer!
    As I sit here typing this I am looking at the Offset Modal Wheel chart handout that Emmett gave me (which is right at home with my Bach Action Figure and signed copy of Tony Levin's "Stick Men").
    While I feel like I understand exactly how it is laid out and works, the ability to harmonize these newfound scales eludes me. I am all too familiar with the concepts of harmonizing the first spoke (major scale) but what of the others? Does the rule of 1, 3, 5 for triads still follow for the augmented tonic and dominant for the outside two Wheels?
    I really want to start composing with these new scales but without knowing how to build a good harmonic support under these exotic sounding intervals, I feel totality lost!

A post by by Ben "Oceans" Weber to on Nov. 23, 2010

    A little late here, but Emmett's system is really, really interesting. I certainly don't have a handle on it but I aim to incorporate it into my theory studies, and then to do some spontaneous chord progressions based on it. What would be a good progression to practice with the Offset Modal System? Which scales to use for melodies over what left hand chords? I guess I am trying to simplify it a bit more than maybe it should be though? Any cool ideas?

Emmett's reply

Thanks to Steve and Ben for keeping that fire burning, and yes I do have an approach to my OMS that might help you get started on any polyphonic instrument, whether it be frets, keys or The Stick. Here it is in bare form:

- Play or arpeggiate a C7 chord with your left hand and find a major scale with your right hand that lowers the 6th and 7th degrees of that scale, including the flatted 6th at Ab and the flatted 7th at Bb. These seven notes then, are your "Single Offset Modal" scale for this particular key. Improvise a melody here, backed by the C7 chord, and try to enjoy the serene balance of some ancient Arabian mood (not allowing current Middle East politics to enter your mind or intrude on tranquility.) This Offset Mode ascends by two whole tones from the C root, and it descends from the root by two whole tones as well - five notes in a row that are related by whole steps.

- Now move your left hand down in pitch by two frets and let the Bb7 chord accompany the same 7-tone scale (not changing any melody notes). Reflect on that for a while, as to how the new chord influences your melodic ideas. Then move back and forth between these two 7th chords, four beats to each chord if you like. The C7 chord together with the 7-tone OMS scale spells out a complete C9b13 chord. Seen from Bb7, the combined sound adds up to a Bb9#11 chord.

- With your right hand always playing within this same "Offset" scale, move your left hand to F minor6 (it could also be F minor with a natural 7th (also known as "F minor major 7th"). With C7 as the key center (acting as the Roman numeral I chord), you now have enough chords for a song, and can move to the IV chord (F minor6) as a sub-dominant minor, and to the bVII chord (Bb7) as a substitute dominant 7th chord. (In a jazz context, 7th chords with their roots separated by minor 3rds often make good substitution chords, as with Bb7, C#7 and E7 all being interesting substitutes for the dominant G7 in the key of C.)

- Extending your left hand to include more of the OMS network of chords at this particular key center of C, move from F minor to its own relative major, Ab major7 (don't change any notes in the right hand). This introduces a super-Lydian scale with every note raised that can be raised, even the 5th degree. Then shift back to F minor, or move parallel from Ab major7 back to Bb7 and back to C7.

- So far you've got four OMS chords out of a possible seven in this seven degree network with which to improvise or compose a song. Next I recommend E7, which acts as another substitute dominant 7th chord. It's a III 7th chord and combined with your OMS melody produces a Middle Eastern sounding E b9#9b13 chord.

- There are then only two chords still to be found in this network of seven basic chords, where each has a root of one of the seven "Offset" scale degrees (C, D, E, F, G, Ab and Bb). In the left hand we already have C7, E7, F minor, Ab major and Bb7 and all that's left is D minor7b5 (II minor) and G minor7b9b13 (the real dominant 7th or V7 chord in the key of C which can also be played in a G7#9 blues style voicing). This II minor7b5 to V7#9 progression is equivalent to the familiar romantic "turnaround" progression from VII minor7b5 to III7, leading to VI minor or A minor, the relative minor of C.

- With these seven chords you can play the Single Offset Modal Network at the middle Wheel on my charts. Then, just for starters using the outer Wheel's Double Offset Mode, you can create an eight-tone scale from the above seven, simply adding a "wild note" that can bend, blues style, from Bb to B. Your C chord, then, can fluctuate from the flatted 7th to a natural 7th - the cliched call of the siren. Interesting variations then happen at all chords, including a dominant G7 with a major and minor 3rd (for a #9 chord), also the substitute dominant E7 with a perfect 5th.

To broaden the perspective, please keep in mind that your left hand C7 chord need not be the chosen tonic or Roman numeral I chord. Any one of the seven chords can be your home base on "tonic" (with its own Roman numeral I), depending on your mood while improvising or on the song you're composing, whether it be in an altered major, an altered minor or an even more exotic Offset Mode.

An F tonic with the same seven notes accommodates the melodic minor scale. An E tonic creates a flamenco mood with a Middle Eastern color, going from E7 to Fm6 to G7 - lots of combinations and possibilities.

At the next broader view, chromatic transposition multiplies all these possibilities by twelve keys. Your C7 chord with its b13 (or flatted 6th scale degree), and with its wavering 7th degree (borrowed from the outer Double Offset Modal Wheel) can simply be transposed as a block to C# or to D, and so on. Imagine my Triple Wheel chart as a musical game board where you rotate the chromatic lettered notes at an outermost concentric ring.

I wish I could broaden my OMS beyond these boundaries, but there the universe becomes dissolute, expanding faster than light speed, and we're once again alone (lights out). That is, if I "offset" any more modal notes besides the Greek Ionian 1st and 5th degrees, I'm left with a meaningless jumble of chromatic notes. The center simply "will not hold".

And there you have the defined limits, as far as I've explored, of my musical "Parallel Galaxy".

Best, Emmett.