Here's a great excerpt from a Barry Harris workshop where he introduces an interesting diminished concept, which he (jokingly) calls his "personal scale". It produces a very cool jazz sound by a quite unexpected means. The video is a bit piano-focussed so I thought it might help some guitar players to have a summary from our point of view of the main idea.

There are seven major scale modes, which you can think of as major scales built on 7 different tonics suspended over a single root note. So over a C root we can play the notes from C Major (Ionian), Bb Major (Dorian), Ab Major (Phrygian), G Major (Lydian), F Major (Mixolydian), Eb Major (Aeolian) or Db Major (Locrian). But there are 12 notes in music; what happened to the other five? Step inside...

The Major 7 arpeggio (1 3 5 7) has many uses; it can be superimposed over harmonies in all kinds of ways and I use it a lot. If you flatten the fifth (1 3 b5 7) you get a new sound with different applications. Here I'll talk about some of the possibilities.

I've been exploring some choices for minor chords that don't contain the b3, which give a rather open, not-very-minor quality to your lines. They can work over other chord types too. So if Locrian just isn't doing it for you any more, step inside.

I've committed to delivering a free mini-course called "Introduction to Scale Theory with Applications", starting in February 2013. The course will cover a lot of ground and if you're registered during the time it's going on I'll be running Q&A / discussion threads alongside the video lectures. If you come too late you can still watch the videos and drop me a line on Reddit if you need help. Now, I suppose I'd better get down to writing the lectures...

I've been experimenting with drawing graphs of scales for a while now, and have a few ideas on the subject; maybe even enough for an ebook one day. I'm particularly pleased with my latest batch, some selections of which I thought I'd share with you here. Consider them your Christmas present, valued reader.

Just wanted to say that with the launch of Spectral Analysis of Scales, downloads of my three ebooks have whizzed past 20,000 since the first one came out nine months ago. Many thanks to everyone who read one or more of the books and helped spread the word; rest assured there's more in the pipeline for 2013!

Next year the term "deliberate practice" will be twenty years old; in that time it has gradually moved out of the academic world and become a phrase uttered in hushed tones in musical, sporting and other spheres. What does it mean and how can we use it?

If you've ever worked on developing speed on guitar you've probably heard references to "muscle memory". But what is this mysterious facility? Is it something real or just a part of musicians' folklore? Can we do anything to make our learning more efficient, or should we be suspicious of "automatic" playing as less creative?

I "discovered" a scale about a month ago when playing with the Ionian b2 (which is now, by the way, part of my regular improvising vocabulary). At the time I thought it was just a curiosity but I liked the sound and since then I've seen it pop up in a few other places.