Auditory Processing Terms

Question 1

Precedence effect

Answer 1

The tendency to perceive the direct and immediate repetitions of a sound as coming from the same position or direction even if the immediate repetitions coming from another direction are louder.

Question 2

Temporal fusion

Answer 2

When reflected sound reaches the ear within 10 to 30 ms of the original sound, the direct and reflected sounds are perceived as a single sound. This effect gradually disappears as the time interval between direct sound and reflected sound increases.

Question 3

Direct sound

Answer 3

Sound waves that reach the listener before reflecting off any surface. First sound.

Question 4

Early reflections

Answer 4

Early sound, reflections of the original sound that reach the listener within about 40 to 50 ms of the direct sound

Question 5

Later reflections

Answer 5

Reverberant sound, the result of early reflections becoming smaller and smaller and the time between them decreasing until they combine, making the reflections indistinguishable. Ambiance

Question 6

Predelay

Answer 6

The amount of time between the onset of the direct sound and the appearance of the first reflections. Not natural, manufactured.

Question 7

Reverberation

Answer 7

Multiple blended, random reflections of a sound wave after the sound source has ceased vibrating. The types of reverberation in current use are digital, convolution, plate, and acoustic chamber.

Question 8

Decay time

Answer 8

The length of time it takes a sound to die away - the time it takes a sound to decrease to one-millionth of its original intensity, or 60 dB-SPL. Source Sound has to stop.

Question 9

Echo

Answer 9

Sound reflections delayed by 35 ms or more that are perceived as discrete repetitions of the direct sound

Question 10

Flutter echoes - (standing waves)

Answer 10

Echoes between parallel walls that occur in rapid, even series

Question 11

Angle of Incidence

Answer 11

Angle at which sound hits a surface. Must equal the angle of reflection. Bass frequencies could go anywhere

Question 12

Azimuth

Answer 12

The angle the sound source makes compared to the imaginary straight line that is drawn from within the head through the area between the eyes. Vertical Plane.

Question 13

Best mixing level in dB

Answer 13

75-80 dB SPL. 90 dB is fine for short periods of time

Question 14

Cochlear Place Tuning

Answer 14

The hair cells in the organ of Corti are tuned to certain sound frequencies by way of their location in the chochlea due to the degree of stiffness in the basilar membrane. Different locations in cochlea react to different frequencies

Question 15

Duplex Theory

Answer 15

In general, higher frequencies are localized via IIDs and lower frequencies by ITDs. Time and level differences, How we hear sound in a horizontal plane.

Question 16

ITD’s

Answer 16

Interaural Time Differences, different arrival times due to the distance between the ears, usually affects lower frequencies

Question 17

IID’s or ILD’s

Answer 17

Interaural Intensity Differences or Interaural Level Dfferences. Different arrival intensities due to the diffraction or shadowing caused by the head as an obstacle . Affects higher frequencies

Question 18

Summing Localization

Answer 18

Occurs when two or more coherent sound waves arrive within a limited time interval and only one sound sensation is perceived

Question 19

@ 45 degrees - 300us

Answer 19

Difference between your two ears, angle and time

Question 20

millisecond

Answer 20

one thousandth of a second

Question 21

The cochlea is tuned to what frequency at the largest and smallest point?

Answer 21

20 Hz at the largest point and 20 kHz at the smallest.