Listening to music can help us focus in busy and noisy office environments. But to help us be truly productive, the kind of music we listen to should compliment the work we are doing, according to Chris Bailey, author of The Productivity Project.

Whether he’s writing or completing research for his next book, Bailey is almost always listening to a playlist. In February, the author conducted an experiment to see how music impacted his productivity. He listened to different types of music every week for five weeks:

Week one: Instrumental music

Week two: Slow jams

Week three: Pop music

Week four: Rock music

Week five: No music

The results were revealing: The type of music affected his work differently depending on how difficult or mundane the task.

Simple and familiar music were the most productive, especially during habitual tasks

Overall, listening to music fired up Bailey’s ability to concentrate, especially during boring work. It also drowned out distracting background noise.

“When we work on tasks that are habitual like doing data entry or mindlessly doing some other things, we have a bit of attention to spare,” Bailey tells NBC News BETTER.