Though music startup Focus@Will streams music that people can ignore, it appears that users aren’t ignoring them.

The Echo Park company announced Wednesday that it has opened its beta test to the public and already has 9,000 users. While that’s still a small number, more notable is the company’s retention rate. About 90 percent of users have come back to the site after their first visit.

“We have been astounded at the positive response we have received from our patrons over the past month and are extremely pleased to see the impact that our project has had on people,” Will Henshall, chief executive of Focus@Will, said in a statement.

Focus@Will has scientifically designed playlists that help people focus. The music is meant to fade into the background while the listener, for example, studies for an exam.

The company launched its product in private beta late last year. With the public launch, it has added tracks and made some tweaks to its algorithm for selecting music.