Improvising in minor keys: The Bebop Minor scale

The Bebop Minor Scale
For young players looking for a scale for improvising in minor keys, the Bebop Minor scale is an excellent option. It is spelled as follows:
1, 2, b3, 4, 5, b6, b7, 7, 8

This is a natural (Aeolian) scale with a raised seventh added to it. Some people, such as Randy Halberstad, refer to this as the bebop harmonic minor scale. Mark Levine calls it the Bebop natural minor scale. The so-called "bebop scales" are normal diatonic scales or modes with one extra passing note added so that there are 8 different notes in the octave. The bebop minor scale is the relative of the bebop major scale, which has a #5 added to it. Such scales, for bebop players, facilitated the long flowing quaver lines favoured by bebop musicians from the 1940's on.

Whatever we call it doesn't really matter. The important thing is that is an effective choice for improvising in a tune, or section of a tune, that is in a minor key. That is a tune with a minor key centre, especially if there is V - I harmony or II-V-I harmony present. The bebop minor scale, starting on the tonic, emphasizes the chord tones in a minor 7 chord (1, b3, 5, b7). When it is played from the leading note (the raised seventh) it outlines chord tones from chord V in the minor key (3, 5, b7, b9). It is also a close match to chord II (b6, 1, b3, b5).

In fact, using a Shearing-style block chord harmony approach, the bebop minor scale can pretty effectively outline every chord in a minor key, just by changing emphasis (or mode). Take care with the raised 7th against chord IV, which can be a little ugly.

Here is an example of how a beginner improviser might effectively play, using a key centre approach, through a tune with two key centers. Bernie's tune is a 32 bar AABA song. The A sections are in D minor (I, VI, II, V, I) and the B section is in Bb major (I, VI, II, V). In the A sections, then, use the D bebop minor scale, which can easily outline all the chords. In the B section use the jazz pentatonic (major blues) scale.

This approach gives the less experienced improviser something they can play without too much difficulty that will allow them to sound good and in style. There are other things more advanced players do, but this is a really effective "entry level" technique. In fact, it is more than that, as it is very close to what many professional players do too. This is a great thing for anyone who wants to learn how to improvise.

To summarise, then: If a tune (or section of a tune) is in a minor key, the bebop minor scale is a great choice.