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Production Testing Seminar

March 10th, 2022. 9.00am and 2.00pm Eastern US time (6.00am and 11.00am West Coast time)

In this short seminar, Les Quindipan explores the use of SoundCheck for end-of-line production testing. He discusses typical test configurations and the type of measurements that can be made, how to set pass/fail limits and how to optimize tests for high throughput.

He will also explain how SoundCheck is easily scaled for high volume production testing, with such features as external control via another program and auto-saving data to databases, and how SoundCheck’s capabilities are easily expanded through the use of custom steps to control all types of devices and test fixtures.

This seminar will be of interest to anyone considering a production line implementation of SoundCheck, or curious as to how to transition R&D measurements to fast and effective end-of-line test.

Note: We will be repeating this seminar in conjunction with our exclusive distributor in China, S&V Samford, a sign-up will be available shortly.

Microphone Polar Plot Substitution Method Using Outline ET250-3D

This sequence measures the directional response of a microphone and graphs the result as a polar plot. A log sweep stimulus is played from 100 Hz to 10 kHz at each angular increment, and the acquired waveform is analyzed using the Time Selective Response algorithm. This method allows the test to be performed in a non-anechoic environment by placing a window around the direct signal, eliminating the influence of reflections. Commands are sent automatically to the Outline ET250-3D turntable via an ethernet connection, instructing it to move in 10 degree increments after each measurement. The sequence measures the response every 10 degrees from 0 to 180 and mirrors the polar image, which simulates a full 360 degree polar and saves test time. The response at each angular increment is compared against the on-axis response to create a normalized curve. This removes the influence of the device’s frequency response and sensitivity, such that the polar plot only shows the directional response. The final display also contains a graph of the directivity index in decibels versus frequency.

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Microphone Acoustic Overload Point (AOP)

This sequence measures the acoustic overload point (AOP) of a microphone – the SPL required to produce 10% THD @ 1kHz from the microphone’s output.
A 1 kHz amplitude sweep from a calibrated source speaker is applied across a range from 120 dB SPL to 135 dB SPL.The recorded time waveform is then analyzed using the HarmonicTrak algorithm to produce a Fundamental and THD vs. Level curve. An intersection post processing function identifies where the THD curve intersects 10% and that level is is used in a limit step to produce a Pass/Fail AOP verdict.

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Online Seminar: Microphone Measurement Basics

Sept 17, 2020. 9.00am and 2.00pm US East Coast time  (6.00 am and 11.00 am West Coast time)

Microphone test in Anechoic chamber (photo courtesy of Shure, Inc. Used with permission.)

In this 60 minute online seminar, Listen’s Technical Support Manager, Steve Tatarunis discusses Microphone Measurement Basics.

Listen, Inc’s SoundCheck electroacoustic test system is used by the world’s leading OEMs and their contract manufacturers on thousands of production lines worldwide. Although it can be used for testing a wide range of devices including speakers, microspeakers, headphones, headsets, smart devices, cellphones and more, this seminar will focus on microphones.

In this online session, Steve Tatarunis will cover the basics of microphone testing, including:

  • Common microphone types and how they work
  • Microphone specifications
  • How to measure microphones using the two standard methods available in SoundCheck
    • Substitution method
    • Equalized speaker method
  • R&D and production test environments
  • Important measurements such as frequency response, sensitivity, etc.

There is no charge for this seminar, but registration is required. Please sign up below. Note that you will be sent login details the day before. The same login details will offer access at both times, so you can choose to attend the one most convenient to you.

Microphone Measurement Basics

Sept 16, 2020. 10am China time

In this 60 minute online seminar, S&V Samford presents Listen, Inc. Technical Support Manager, Steve Tatarunis discussing Microphone Measurement Basics.

Listen, Inc’s SoundCheck electroacoustic test system is used by the world’s leading OEMs and their contract manufacturers on thousands of production lines worldwide. Although it can be used for testing a wide range of devices including speakers, microspeakers, headphones, headsets, smart devices, cellphones and more, this seminar will focus on microphones.

In this online session, Steve Tatarunis will cover the basics of microphone testing, including:

  • Common microphone types and how they work
  • Microphone specifications
  • How to measure microphones using the two standard methods available in SoundCheck
    • Substitution method
    • Equalized speaker method
  • R&D and production test environments
  • Important measurements such as frequency response, sensitivity, etc.

The presentation will be in English, but slides will be in English and Chinese.

There is no charge for this seminar, but registration is required. Please sign up below.

麦克风测试基础篇网络研讨会

中国时间2020年9月16日星期三上午10点

在这个60分钟的在线研讨会中,声振环保仪器有限公司以及Listen,Inc.技术支持经理Steve Tatarunis,会与大家探讨麦克风测量的基础知识。

Listen公司的SoundCheck电声测试系统广泛用于全球领先的原始设备制造商及其合约制造商的成千上万条生产线。虽然它可以用于测试各种各样的设备,包括扬声器、微型扬声器、耳机、耳麦、智能设备、手机等等,但本次研讨会将着重讨论麦克风。

在这次在线研讨会中,Steve Tatarunis将涵盖麦克风测试的基础知识,包括:

  • 常见的麦克风类型及其工作原理
  • 麦克风的规格
  • 如何使用SoundCheck的两种标准方法测量麦克风
    • 对比测试法
    • 标准均衡音源测试法
  • 研发和产线测试的环境
  • 重要的测试如频率响应、灵敏度等.

这次研讨会将会以英文进行,演示文稿将以中英文显示。不收取任何费用,但是需要提前注册。请在下面注册。

 

Microphone SNR Measurement (Background Noise Method)

This sequence characterizes a microphone’s ability to passively and/or actively reject noise in the user’s environment.  Unlike traditional microphone SNR measurements which calculate a ratio based upon a reference signal and the microphone’s noise floor, this method utilizes a signal (speech played from a mouth simulator) and noise (background noise played from two or more equalized source speakers) captured by both a reference microphone and the DUT microphone.

First a recording of the baseline ambient noise in the test environment is made and a 1/3 octave RTA spectrum is calculated from the recording. Next, the speech signal (mouth simulator) and noise signals (Left and Right speakers) are played consecutively and recorded separately using the reference microphone. A 1/3 octave RTA spectrum is calculated from each recorded time waveform. Next the same measurements are repeated using the DUT microphone. The resulting RTA spectra are then post processed to produce a signal gain spectrum and a noise gain spectrum which are then used to derive the SNR spectrum of the DUT mic. For best accuracy, the Signal and Noise spectra should be at least 5 dB above the ambient noise floor of the measurement environment.

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