4 pitches

When you do this exercise, after about 90 seconds you will start to think "what am I doing here? This is nonsense." A lot of people quit here.

Then 5 or 6 minutes into the exercise, it will start to be even more difficult to continue. "I can't do it any longer. Let me play REAL music." Even more people quit here.

For those that continue, about 8 minutes into the exercise, it will begin to make sense.

If you survive those 10 minutes, you will feel great and kind of sad you had to stop.