Loudspeaker Test Sequences
Measurement of Stereo Soundfield Parameters
The stereo soundfield sequence measures parameters such as Interaural level difference (ILD) and interaural cross-correlation (IACC) using a Head and Torso Simulator (HATS). The spectrum is measured at each ear and calculates interaural level differences (ILD), spectral balance, delay differences, and interaural cross-correlation (IACC). The measurements are made using different time windows, so that the direct, early, late or total parts are separated.
Several different signals are applied to the left and right inputs of the device under test (DUT), and the measurements are made with the HATS left and right ears. Up to 9 measurements in varying positions are made and saved. Results for each position are displayed, and on completion of the testing, means and standard deviations are shown.
Headphone and Headset Test Sequences
EN-50332-2: Measuring SPL of Portable Devices
These two sequences follow the test standard detailed in EN50332-2 for measuring the maximum levels of portable music players and earphones/headphones. This section of the standard covers the individual testing of the devices rather than the combined testing that is detailed in part 1. Note that the physical setup and connections will be different between the two sequences. Please read the hardware and calibration sections of this instruction carefully.
Microphone Test Sequences
Telephone Test Sequences
TIA-5050 Test Sequence for Narrowband (NB) and Wideband (WB) Mobile Handset Phones
TIA 5050 is a US standard with measurement methods and requirements for the receive volume control performance of both narrowband (NB) and wideband (WB) mobile handset phones. The measurements include conversational gain, frequency response, and distortion. Measurements are made at both 2N and 8N handset application forces, with different requirements applied to each. Either Free Field (FF) or Diffuse Field (DF) can be chosen as the Listener Reference Point (LRP) for receive frequency response.
TIA-920-B Sequence for Measurement of Narrowband and Wideband Digital Phones
This sequence tests to TIA 920-B, a comprehensive US dual-bandwidth standard that applies to both narrowband (NB) and wideband (WB) devices. It also allows a choice between Free Field (FF) and Diffuse Field (DF) as the Listener Reference Point (LRP). The current release of this sequence measures digital communications devices with handset features, according to TIA-920.110-B and speakerphones, according to TIA-920.120-B. Support for headset measurements, according to TIA-920.130-B will be added in a future release.
This module is a large structured set of sequences and subsequences which perform all the measurements. Curves and values are shown on the screen, tolerance checks are performed, and data is saved to Excel spreadsheet files. Completely prompted sequences for calibration of all the transducers are included. After a one-time setup with a sound card and other user-specific interfaces, the sequences are automatic. They run by simply selecting, pressing start, and following prompts where user interaction with the device under test is required. The sequence works with approved sound cards for connection to the transducers. Windows audio devices such as USB headsets work directly with SoundCheck®. VoIP softphones also work with SoundCheck, by means of a recommended third-party Windows audio application.
Hearing Aid Compatibility to TIA 1083 and FCC Part 68.316
These two test sequences are designed to test the hearing aid compatibility of a telephone according to the TIA 1083 and FCC Part 68.316 standards. These sequences, which rely on the user having radial and axial HAC probes, play the appropriate test signals, measure the response and compare them to the limits in the standard. These pre-written sequences enable the user to immediately test to the relevant standards, and can be fully modified to meet any custom testing needs if desired.
TIA-920-A Sequence for Wideband Digital Phones
This sequence has been superseded by TIA 920-B test sequence.
TIA-810-B Standard for Narrowband Digital Phones
This sequence has been superseded by the TIA 920-B test sequence.
Wireless (Bluetooth) Test Sequences
Hearing Aid Test Sequences
Hearing Aid Frequency Response Test Sequence
This sequence follows the ANSI S3.22-1996 standard method for testing the frequency response of a hearing aid. An equalized stepped sine sweep from 8 kHz – 200 Hz is played at a level of 60 dBSPL through the anechoic box speaker, and the output of the hearing aid is analyzed with the Heterodyne algorithm to produce a frequency response. Next, the HFA (High Frequency Average) is calculated by averaging the response values at three frequencies (1000, 1600, 2500 Hz). The HFA is then subtracted by 20 dB. Two post processing steps are used to find the upper and lower frequency points at which the response curve intersects this calculated value (HFA – 20 dB). These are the high and low frequency cutoff points.
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 analyzed through the hearing aid. Next, the HFA (High Frequency Average) is calculated by averaging the values at three frequencies (1000, 1600, 2500 Hz), and this value is checked with a limit step. The Max OSPL is calculated by finding the maximum point on the broadband response. A limit is also applied to this value.
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 run through a post processing step, which calculates the release time. It does this by calculating the time it takes the device to stabilize within 4 dB of its steady level.
AGC Hearing Aid – Reference Gain & EIN Test Sequence
This sequence performs two of the measurements from the ANSI hearing aid test standard S3.22-1996. The first part, in accordance with section 6.7 of the standard, helps the user set the reference test gain for the hearing aid, which is used for multiple measurements in the standard. The second part, from section 6.12, tests the equivalent input noise (EIN) of the device.
ANSI S3.22 Hearing Aid Test Sequences
These sequences include all the tests from ANSI S3.22:2014 as well as some of the additional ‘Annex C’ tests from the 2014 ANSI standard. This guide describes the basic functionality of each sequence and details the process of hardware setup and calibration.
Each test, as outlined in the standards, is contained in a single test sequence and can be run independently. The ‘— HA ANSI S3.22_2014 Product Test — master sequence’, calls all the required individual test sequences to run a complete standard test suite. It also creates or recalls a limits file according to the definitions in ANSI S3.22:2014 and assists in setting the correct Reference Test Setting for the device being tested. The name of the master sequence is bracketed by dashes to separate it from the individual test sequences.
Smartphone and Tablet Test Sequences
Audio Electronic Test Sequences
EN 50332-1 – Max. SPL of Portable Audio Devices
This sequence follows the test standard detailed in EN50332-1 (2013) for measuring the maximum sound pressure for portable music players and the earphones/headphones they are bundled with. The test involves loading a weighted pink noise stimulus file (as specified by IEC 268) onto the portable device and playing it through the earphones at the player’s maximum volume.
EN-50332-2: Measuring SPL of Portable Devices
These two sequences follow the test standard detailed in EN50332-2 for measuring the maximum levels of portable music players and earphones/headphones. This section of the standard covers the individual testing of the devices rather than the combined testing that is detailed in part 1. Note that the physical setup and connections will be different between the two sequences. Please read the hardware and calibration sections of this instruction carefully.
General (non-application-specific) Test Sequences
Background Noise Simulation to ETSI ES 202 396-1 Standard
This Background Noise Simulation sequence follows the ETSI ES 202 396-1 standard. It will automatically calibrate a standardized 4.1 speaker / subwoofer setup in accordance to the ETSI ES 202 396-1 standard “Loudspeaker Setup for Background Noise Simulation” and provide an equalized, calibrated playback solution to stress your device in a standardized and repeatable way.
Included with the sequence is a library of real world binaural recordings from the ETSI standard: cafeteria, pub, crossroad, vehicle, single voice distractor, and office noises. Custom or user-defined binaural recordings can also be used to create background noise tests directly applicable to your product. This sequence has many applications including evaluating ANC on headphones, noise suppression on communication devices, voice recognition testing of smart speakers / IoT, SNR optimization of microphones on telepresence devices and beamforming directionality studies of microphone arrays.
