MGRLB soundtrack, and public opinion on music in games

LD39 was my first attempt at a rhythm-based game, so I put more effort than usual into making a catchy and rhythmic soundtrack. You can listen to it on Soundcloud here:

https://soundcloud.com/user-565506175/fredericks-theme

In general, to what extent does music impact the enjoyability of a game? Can a game be good with a mediocre soundtrack? Alternatively, can an otherwise mediocre game be really engaging because of the quality of its music?

(You can also play my game here: https://ldjam.com/events/ludum-dare/39/mountaintop-groovy-robot-laser-battle)