Sound-Sound Interaction

Question 1

Does masking result from the algebraic addition of sound pressure functions as expressed by the Law of Superposition?

Answer 1

No

Question 2

Beats, interference and phasing all result from the _______ of two sound waves together with small differences in frequency or phase

Answer 2

Addition

Question 3

What is masking?

Answer 3

a psychoacoustic process where one sound makes it harder to hear another when they occupy the same frequency range

Question 4

Destructive interference between two waves of the same frequency is at its greatest when the phase difference between them is _________

Answer 4

180°

Question 5

What is diffraction?

Answer 5

the inability of a sound wave to bend around an obstacle depending on its wavelength compared with the size of the obstacle

Question 6

What is destructive interference?

Answer 6

When two waves have the potential to cancel or attenuate because they are out of phase

Question 7

Beats occur between two waves of similar but not identical _________ and are heard as periodic changes of ________

Answer 7

Frequency, Loudness

Question 8

What are two phenomena are examples of amplitude modulation

Answer 8

first-order beats, tremolo

Question 9

What are second-order beats?

Answer 9

arise from mistuned harmonic interval, exhibiting internal phase shifts. do not change in overall amplitude

Question 10

Phasing produces a ________ of specific frequencies and therefore a striation of the resulting spectrum, without any ________ effect

Answer 10

Cancellation, beating

Question 11

The beat frequency between two tones of frequency X and Y which are close together is ___________

Answer 11

X-Y

Question 12

The perceived pitch of two tones beating together is the ________ of the two frequencies

Answer 12

Average, (X+Y)/2

Question 13

Does beating involve time delays between two or more sounds?

Answer 13

No

Question 14

Frequencies which cancel during phasing are the _____-numbered harmonics of the frequency whose period is twice the time delay involved

Answer 14

odd

Question 15

The spectral change caused by phasing is similar to that of a _______ filter

Answer 15

comb

Question 16

Environmental phasing is heard as a dynamic change of ________

Answer 16

timbre

Question 17

The level of masking can be defined in ______ as the threshold shift necessary to restore a masked sound to audibility

Answer 17

dB

Question 18

Masking is greatest when two sounds have their energy lying within the same ______

Answer 18

Critical band

Question 19

Critical bandwidth can be measured through sine tone masking experiments with ______

Answer 19

narrow-band noise

Question 20

Two sine tones sound with maximum roughness between them when separated by __________ which is _________ than a musical semitone

Answer 20

1/4 the critical bandwidth, larger

Question 21

Two sine tones sound with maximum consonance when separated by __________

Answer 21

a critical bandwidth

Question 22

_____________ appear because of non-linear processing in the auditory system, which creates added frequencies in the perceived result

Answer 22

Combination Tones

Question 23

What is the choral effect

Answer 23

enhancement of a musical ensemble because of small differences in pitch and attack times - adds internal complexity to the sound

Question 24

Does echo enhance the sound of a musical ensemble

Answer 24

No - it might mask the sound

Question 25

Tones that are widely separated in pitch and repeat more than 5 tones/second, will be perceived as segregated, a phenomenon also known as _________

Answer 25

fission

Question 26

The connection of the two auditory nerves from each ear to the hemispheres of the brain can be described as _________

Answer 26

60/40% contralateral