This is what I found online: "<span>For a person with normal hearing, when it comes to pitch the human hearing range starts low at about 20 Hz. That’s about the same as the lowest pedal on a pipe organ. On the other side of the human hearing range, the highest possible frequency heard without discomfort is 20,000Hz. While 20 to 20,000Hz forms the absolute borders of the human hearing range, </span>our hearing is most sensitive in the 2000 - 5000 Hz frequency range<span>." So i'm guessing it's 100,00 since none of those are lower than 20
