Entries by Devin Vaillancourt

Microphone Frequency Response and Sensitivity Test Sequence

This is sequence is a basic example of the two most common microphone measurements: frequency response and sensitivity. A stepped sine sweep is played from 10 kHz to 100 Hz through a source that has previously been calibrated to produce 1 Pascal across the frequency band. The recorded signal is analyzed with a Heterodyne analysis […]

Hearing Aid Input vs Output Test Sequence

This sequence follows the ANSI S3.22-1996 standard method for testing hearing aids with AGC (automatic gain control). The test uses an amplitude sweep from 50 90 dBSPL played through the anechoic test box speaker. This sweep is repeated at four frequencies (1 kHz – 4 kHz) in 1 kHz increments. The output of the hearing […]

Hearing Aid OSPL 90 Test Sequence

This sequence follows the ANSI S3.22-1996 standard method for measuring the OSPL curve, the HFA value, and the Max OSPL value for a hearing aid. An equalized stepped sine sweep from 8 kHz – 200 Hz is played at a level of 90 dBSPL through the anechoic box speaker, and a broadband response curve is […]

Release Time Hearing Aid Test Sequence

This sequence follows the ANSI S3.22-1996 standard method for testing the release time of AGC (automatic gain control) hearing aids. A 2 kHz sine tone is played at 90 dBSPL for 1 second and then immediately drops to 55 dBSPL for 2 more seconds. A band limited time envelope (1.5-2.5 kHz) is created and then […]

Loose Particles Sequence

This sequence demonstrates how to use SoundCheck to detect loose particle defects in loudspeakers. Loose particles typically reveal themselves as randomly spaced impulses, so they may not be detected when performing frequency based measurements such as THD, even though they can be clearly heard as undesirable artifacts. The loose particle algorithm, which is an available […]

Complete Test Sequence

The purpose of this sequence is to perform a full suite of basic measurements for a loudspeaker. A 500 mV stepped sine sweep from 20 kHz to 50 Hz is played through the speaker and measured via two channels of the audio interface. A calibrated reference microphone is connected to one of the channels, and […]

Bluetooth Headset Test Sequence

The purpose of this sequence is to test a Bluetooth headset using a mixture of analog and digital channels. First, a Multitone stimulus is created with SoundCheck, played back over the Bluetooth headset (at 8 kHz) and recorded by a head and torso simulator’s ear (at 44.1 kHz). Then the same Multitone stimulus is played […]