There is this mysterious division of your brain that allows your hands to function independently of one another. As a keyboard player, the development of this skill is an interesting journey.
To get you started, here are six ostinato bass lines I’ve written that are meant to be looped and improvised over. The first step will be for you to play these securely and evenly. After you feel you can play each one smoothly, try having a conversation with someone while you continue to play it. That will be a sure test!
Once you are comfortable with each left-hand pattern, add your right hand and play freely over the top. Follow my recommended fingerings to help you get the most out of these patterns. (Alternate fingerings are in parentheses.)
Example 1 is a nice 4/4 pattern based on a D blues scale, but with a small twist—the minor second, an Eb
Example 2 is also in 4/4 and has D as the tonal center, but it weaves in an interesting way. Your hand will become spider-like as you get into this loop.
One of the things that is always on my mind is creating note patterns that have a certain “cool” feel. Example 3 is in ¾ time and plays with changing between major, minor and Phrygian in a small amount of time while keeping A as the center.
Example 4 is a 4/4 pattern around B that has an almost Emerson-like feel. Try both recommended fingerings and remember to breathe!
Let the odd meters begin! Creeping up chromatically gives Example 5 its flavor. As another small challenge, see if you can figure out how to play this in different keys.
I’m really into working the compression/expansion of my hands. Example 6 does just that by starting with an open interval of an octave and then closing down to the smallest interval on the 5th beat before looping.
Check out Jordan’s Online Conservatory at www.jroc.us for these kinds of exercises in all keys, as well as video, MIDI files, audio, and tons more great stuff for keyboardists. These examples transcribed by Eren Basbug.