BRUEL & KJAER HATS 4606, Руководство пользователя

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High-frequency Head and Torso Simulator (HF HATS) Type 5128 – User Manual 54
MRP Mouth Reference Point. The point on the reference axis, 25 mm in front of the lip
plane. The reference axis is the line perpendicular to the lip plane containing the
centre of the lip (CL). See Fig. 3.1
Occluded-ear
simulator An ear simulator which simulates the inner part of the ear canal, from the tip of an ear
insert to the ear drum.
Sidetone path The acoustic path by which a person’s speech is heard in their own ear at ERP.
Sound Any pressure variation that the human ear can detect. Just like dominoes, a wave
motion is set off when an element sets the nearest particle of air into motion. This
motion gradually spreads to adjacent air particles further away from the source.
Depending on the medium, sound extends and affects a greater area (propagates) at
different speeds. In air, sound propagates at a speed of approximately 340 m/s. In
liquids and solids, the propagation velocity is greater – 1500 m/s in water and
5000 m/s in steel.
Sound level or sound
pressure level The level in decibels of the pressure variation of a sound. See also decibel .