export_dsp terms Flashcards

Question 1

Q

ERL(EchoReturnLoss)

Answer

A

Lossinlevelofthereceiveaudio(echo) betweenthemixer’soutputandthe mixer’smicrophoneinput

Question 2

Q

AchieveTargetLevel

Answer

A

24dBsignaltonoise

Question 3

Q

SameLevelToAllEars

Question 4

Q

AdequateElectricalSignaltoNoise

Question 5

Q

CriticalDistanceGoals for Mics

Answer

A

UnidirecionalMic -
Adequate Talker
Excellent Talker

OmnidirecionalMic

Adequate Talker
Excellent Talker

Question 6

Q

PAG

Answer

A

Poten2alAcous2cGain

Question 7

Q

NAG

Answer

A

NeededAcousticGain

Question 8

Q

What must be higher PAG or NAG

Answer

A

ThePAGmustbegreaterthantheNAGforthesoundsystemtowork

Question 9

Q

When to use NC (noise Cancellation)

Answer

A

When audio level is less than 24Db of Noise floor.

Question 10

Q

AdverseEffectsofNoise

• Ifspeechtonoisera2ois:

Answer

A

– 0-10dB-intelligibilityisunacceptabletopoor
– 10-20dB-intelligibilityispoortofair
– 20-25dB-intelligibilityisfairtogood
– 25dB+-intelligibilityisgoodtoexcellent

Question 11

Q

ConvergenceRate

Answer

A

TherateatwhichtheAECfiltermodelcomestoasolu2onoradaptstotheroom
• Dependsontheamountofandcharacteris2csofthereceiveaudio
• Convergencespecsareuselesswhencomparingproductsunlessallcondi2onsareiden2cal

Question 12

Q

ConvergenceRules

Answer

A

Convergenceoccurswhenreceiveaudio onlyispresent.Inotherwords,whenthe farsiteistalkingandthelocalsiteisquiet

Question 13

Q

NLP-NonLinearProcessor

Answer

A

Becauseofroomdynamics,AECwillnotremoveallacous2cecho.NLPisused
axertheAECtosuppressresidualacous2cecho.

Question 14

Q

AEC ( Acous;cEchoCanceler)

Answer

A

– Isuserselectableforeachmicrophoneinput
– Mustcontaintheaudiothatoriginatesinthefarendroom(s)
– Mayoxencontaintheaudiothatfeedstheroom’sloudspeaker(s)
– Mustnevercontainitsownaudio

Question 15

Q

PTT

Answer

A

PushtoTalk

Question 16

Q

PushtoTalk(PTT)Mode

Answer

A

Must freeze AEC otherwise AEC module may send an inverse transmit signal.

Question 17

Q

Avrave Talker SPL

Answer

A

64 dBa SPL

Question 18

Q

How many dB does each additionl Speakers at the same SPL add?

Question 19

Q

ERL

Answer

A

Echo Return Loss

Question 20

Q

ERLE

Answer

A

echo return loss enhancement

Question 21

Q

NOM

Answer

A

Number of Open Microphones

Question 22

Q

AEC

Answer

A

Acoustic Echo Cancellation

Question 23

Q

NC

Answer

A

Noise Cancellation

Question 24

Q

AGC

Answer

A

Automatic Gain Control

Question 25

Q

ALC

Answer

A

Automatic Level Control

Question 26

Q

Crest Factor

Answer

A

The difference between peak and average audio levels

Question 27

Q

SNR

Answer

A

Signal to Noise Ratio