Day 2 AP-GRAS Seminar

What is the purpose for the use of an ear simulator when testing headphones?

• To realistically simulate the impact of the human head and torso in the sound field

• To provide an acoustical loading similar to how a human ear will load the headphone

• To provide an ear canal for realistic placement of a headphone

Which of these can be considered as a limitation for the IEC 60318-1 ear simulator for headphone testing?

• It can reliably be used only up to 8kHz

• It has a short ear canal

• You don´t have an ear canal so in-ear headphones and ear buds cannot be tested

Which of these can be considered as a limtation for the IEC 60318-4 ("711 coupler") era simulator?

• It has a big resonance at 13.5kHz and that can affect the reliability of the test results in the high freq range

• It cannot be used to test in-ear headphones

• The ear canal is too short

Which GRAS test fixtures can be equipped with a mouth simulator?

• GRAS 45CB and 45CA

• GRAS KEMAR and 45CA

• GRAS 45CC and KEMAR

What of the following things is important to remember when using a Mouth Simulator for headset test?

• To make the signal coming out of the mouth simulator as loud as possible

• To calibrate the Mouth Simulator´s frequency response

• To measure the mouth simulator´s output at 1m distance from the mouth

What is important when performing ANC Insertion Loss Tests?

• That the test fixture has enough self-insertion loss to provide reliable test results

• That the self-noise of the ear simulator´s microphones are low enough

• That the test is performed with a fixture using "711 couplers"

Which of the below are Bluetooth Profiles commonly used in Headset Measurements

• A2DP

• AVRCP

• HFP

• HSP

What does PDM stand for?

• Pulse Digital Modulation

• Primary Driver Mode

• Pulse Density Modulation

• Pulse Data Modulation

Which of the below are Speech Intelligibility Measurements?

• PESQ

• STIPA

• POLQA

• ABC-MRT

What Does the A in ABC-MRT stand for?

• Articulation

• Acoustic

• Audio

• Absolute