has anyone heard of...

[takashi1224]

Has anyone heard of"pitch axis theory"?

I have seen it at joe satriani's
homepage at Satch's(www.satriani.com)
biography.

I have looked everywhere on this topic
but nobody has given me a clear answer.
Please help me.

[StoneDragon]

I couldn't find the mention of "pitch axis" on Joe's site, but he has talked about it before in several guitar magazines. I seriously doubt that you will find any mention of it in conventional theory circles... at least not by that name.

I plan to eventually post some material that deals with the same concept. I've always refered to it as "pivot chords".

In order to understand the concept, you have to have a pretty good grasp of scales and their relationship to chords, as well as how chord progressions suggest certain scales. Given that understanding, the concept is really pretty simple, but it is a powerful compositional tool.

In a nutshell... any note or chord can function in a number of different ways at any given time regardless of what key that note or chord might most likely belong to. jazz players do this all the time by approaching each chord as a separate entity when they solo.

An easy example of this concept in action would be to play a D major chord in the open position (xx0232). Let's say that you are playing a melody out of the D major scale while this chord is playing. Now move the D shape up three frets, but keep the open D note ringing (xx0565).

This new chord suggests a Dmin7 sound, so the melody would have to shift to using the D natural minor scale, the D Dorian mode, or any other minor scale that works with a min7 chord.

The open D note acts as a pivot or axis between two different scales and gives the two unrelated chords a sense of continuity.

I have a piece that I wrote for acoustic guitar that is based entirely on using the open A-string as a pivot between A Lydian, A Phrygian, A Mixolydian and A Aeolian... fun stuff http://www.zentao.com/ubb/cool.gif

[David Mcloughlin]

Anychance of giving an example chord sequence stone ?

[StoneDragon]

Sure... A D E A G D A.

A D E A is in the key of A major

A G D A is in the key of D major but resolves to the V chord (A), so it is actually in A mixolydian.

The A chord acts as a pivot or doorway into two different scales or keys.