In vocal music, the second degree of the scale is often sung somewhere
between an Eb and an E. In instrumental music, various techniques are
employed to achieve the same effect, such as stretching the string while
playing an Eb on a stringed instrument, lipping down an E on a wind
instrument, or striking both the Eb and E simultaneously on a keyboard
instrument. The flatted seventh and fifth also are not always sung or played
exactly on the notated pitch.
Variations on the blues scale that include the natural third, fifth, or
seventh can be used as well. Also, note that if the flatted fifth is
omitted, the resultant scale is the minor pentatonic scale which we consider
below. The minor pentatonic scale can thus be used as a substitute for the
blues scale, and vice versa.
The beauty of the blues scale is that it can be played over an entire
blues progression with no real avoid notes.
If you try playing lines based on this usage (for example, a C blues
scale over a C7 chord) you get instant positive feedback,
since almost everything you can do sounds good.
This unfortunately leads many players to overuse the scale, and to run
out of interesting ideas quickly. One way to introduce added interest when
using the blues scale is to use any special effects at your disposal to vary
your sound. This can include honking and screaming for saxophonists,
growling for brass players, or using clusters on the piano.
Many draw attention to characteristic rhythms associated with 'blues'
music. In fact, the best-known rhythm, called the 'eight-note triplet
shuffle', is found also in jazz and swing. This rhythm is illustrated below.