The goal of this observational study is to learn about the sound-induced vibration level of certain structures in the middle ear in the normal-hearing population. The targeted structures are part of a chain of structures responsible for conducting sound within the auditory system and so their ability to vibrate normally in response to sound is relevant to the diagnosis of conductive hearing loss. The main questions the study aims to answer are: * What are the mean and variance of the normal sound-induced vibration level at two anatomical locations, the umbo of the malleus and the tip of the incus? * Are there any significant differences in these vibrational responses associated with sex or age? Participants will have their ossicular mobility measured with an investigational medical device that sends light into the middle ear and measures the motion-induced phase shift on light reflected from the target structures when a sound stimulus is presented. Standard hearing tests including audiometry and tympanometry will also be performed to confirm the normal hearing status of participants.