The 40k and 80k for cavitators refer primarily to the ultrasonic frequencies, which are 40 kilohertz (kHz) and 80 kilohertz (kHz)。 Frequencies around 30kHz to 40kHz tend to produce more audible sounds, which can be noticeable, especially for those sensitive to noise or with tinnitus. This is because lower frequencies fall within the human hearing range, causing a buzzing or ringing sound.In contrast, higher frequencies like 80kHz move outside the typical hearing range, reducing the likelihood of aggravating tinnitus. While 80kHz devices may produce a higher frequency sound, they are generally less audible. For those new to cavitation, both 40kHz and 80kHz devices can seem similar in use. However, if you're sensitive to sound, starting with an 80kHz device might be preferable. It's also worth noting that 40kHz machines are often more affordable. If you're undecided, we recommend starting with a 40kHz device, as it offers a balance between cost and effectiveness.