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Flashcards in CTS Audio Deck (22):
1

Audio conference data may travel over what transport mediums?

ISDN, IP, POTS

2

An audio conference usually includes what, besides mics?

Line or acoustic echo-cancellation

3

Audio conferences pic up sounds how

A single POD (mic and speaker) or individual mics.

4

The subjective perception of sound is...

Loudness. (yes, poorly worded question)

5

Define decibel

a base 10 logarithmic relationship of a power ratio between two numbers

6

Decibels can be used for what?

Voltage (V), distance, sound pressure (SPL), power (W).

7

Threshold of hearing (dB)

0 dB

8

Very quiet room (dB)

30 dB (.00063 Pa)

9

Office cubicle (dB)

55 dB

10

Normal conversation (dB)

70 dB

11

Yelling (dB)

85 dB (.355 Pa)

12

Rock concert (dB)

115 dB

13

Pain (dB)

130 dB (63 Pa)

14

Smallest dB change a human can hear

1 dB

15

Smallest noticeable volume change (dB)

3dB

16

A _________ dB change is subjectively twice or half as loud.

10 dB

17

If you increase the power (W) by 5dB how much will the loudness (SPL) increase?

5 dB! dB changes in distance, voltage, or power will result in the same dB change in SPL

18

dB reference levels: 0 dB SPL =

.00002 Pa

19

dB reference levels: 0 dBV =

1 V (consumer electronics)

20

dB reference levels: 0 dBu =

.775 V (ProAV electronics)

21

dB reference levels: 0 dBW =

1 W

22

dB reference levels: 0 dBm =

.001W or 1 mW