Listening to a playlist of Christmas music, I heard a bass line that I knew I had heard before in a different context. The line uses a descending “major bebop” scale which is essentially a major scale with an added half-step between the fifth and sixth scale degrees.
As a bass line, playing this scale in a descending pattern over the span of two octaves can fill four bars of 4/4 time and makes for a nice intro.
This first example is played by John Clayton on Diana Krall’s Christmas Songs album on the tune “Winter Wonderland.”
The second example is played by Sam Jones and is used not as the actual intro but as the first four bars of the head on “Sleepin’ Bee” from the album Nancy Wilson/Cannonball Adderley (1961).
Here is the transcription of both lines. I have boxed the scale degrees that are essentially the same in both lines. Jones and Clayton each embellish and end the line slightly differently, but the primary pattern is quite effective and recognizable.