The middle ear both transmits sound and protects against loud noise

Evidence

The function of the middle ear is twofold: (1) to transmit the movements of the tympanic membrane to the fluid that fills the cochlea without significant loss of energy and (2) to protect the hearing system to some extent from the effects of loud sounds, whether from external sources or the individual concerned. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 525

Categorization

• DEFINE: Concise statement of the middle ear’s dual function sets up later material on the acoustic reflex and loud-sound protection.
• corroborated: 4 independent passages support this claim — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 525
• XREF: connects to: Middle ear impedance match is optimal near 1 kHz; The middle ear evolved as an impedance transformer to bridge air-water sound energy loss — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 733; Outer and middle ear structures provide frequency-specific amplification of incoming sound — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 212 (+5 more)

Broader Connections

• Middle-ear muscles automatically stiffen to block loud sounds #expands (0.92) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 541
• An acoustic reflex desensitizes the ear to protect cochlear hair cells #expands (0.90)
• The middle ear amplifies sound pressure through three mechanical mechanisms #expands (0.85)
• The hearing system actively filters and modulates sound more than passively receiving it #expands (0.80) — George Michelsen Foy, Zero Decibels, 558
• The physical structure of the ear itself shapes and constructs perceived sound #expands (0.75) — George Michelsen Foy, Zero Decibels, 561