If you think that you might ever need (or, heaven help us, want ) to play your whistle in some kind of jazz blues jam, then you could do a lot worse than to first have a listen to kwela pioneer Willard Cele. This style of playing isn’t very typical of the kwela that followed, and I think it sounds similar to a clarinet playing USA boogie.
Using a D whistle, the G Blues Scale has a few advantages:
The higher notes on the top of a D whistle pierce through an amplified blues band more effectively.
The G Blues Scale is favored by harmonica players, playing cross harp on the ubiquitous C harmonica.
The G Blues Scale is much easier to finger than the D Blues Scale – G, Bb, C, C#, D, F. And the C-C#-D combo allows the following tidy blues riff on a D whistle:
o o o
x o x
x o x
Here’s an easier blues key on the D whistle – jamming in the blues scale of F#:
E, F#, A, B, C, C#, e, f#.
Here’s what’s great about this scale: 1) the low E let’s you dip beneath the tonic for a very bluesy add-on, 2) the slide from B to C has that quintessentially blues sound, 3) the upper notes of C#, e, f# – when played together – nicely frame the riffs at the bottom of the scale.
(Play the notes slowly and use plenty of tonguing.)