About two years ago, I started an experiment. Every morning, I would listen to the Bach Cello Suites while I began my work day (planning, scheduling, emailing). And almost instantaneously, I noticed an increase in my productivity.
Not sure if it was just the adrenaline rush of performing an experiment on myself or if it was some sort of placebo effect, I decided to keep doing it while taking some notes to mark measurements in productivity. Not only did I see a consistent increase, but I also observed a new added benefit... The music became a habit and would 'zero-out' my mind from anything that might otherwise conflict with my work.