My girlfriend plays violin, she has a much more musical ear than I do. She says everything sounds better since I flipped the switch to BP. She felt before that notes just ended, no decay to them, she says that the notes now sound complete and fuller. I didn't tell what I changed, I just told her that I made a change and asked her if it sounded any better/different. I am not sure what else this switch does to the music... but everything sounds better with the switch in BP mode, not just the lows.