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West Coast Audio Measurement Roadshow Nov 8th-12th 2021

Visit us next week at our West Coast Audio Measurement Roadshow! We’re bringing our truck to various outdoor locations in the Bay area for Covid-safe product demos, previews, refreshments and giveaways (details below). If you haven’t received a personal invite yet, please let us know and we’ll send you full details!

Advanced Microphone Measurements Part 2

Listen’s Support Manager, Steve Tatarunis, discusses some of the more advanced aspects of microphone measurements. This is an expansion of material covered in the Basic Microphone Testing webinar, and part two of the full advanced microphone measurements seminar. Advanced Microphone Test part 1 shows microphone measurements like polar plotting, open loop, active/passive noise rejection, and more. This seminar is of interest to anyone testing microphone characteristics, both in an R&D and production line environment. The tests featured in this seminar can be used both at component level, whether selecting microphones for devices or component QC, or these tests can be performed on finished products like smartphones, smart speakers, and more.

Seminar topics include:

More advanced aspects of microphone testing including:

  • Phase
  • Open loop microphone testing for voice activated devices such as smart speakers, automotive audio, etc.
  • Intermodulation distortion
  • Advanced hardware and test configurations for measuring microphone arrays
  • Beamforming with broadside and endfire arrays
  • Measuring MEMS devices frequency, sensitivity and power supply rejection (PSR) performance

Presenters: Steve Tatarunis
Duration: 40 Mins

Advanced microphone measurements resources

SoundCheck comes with many pre-written sequences including the sequences demonstrated in this seminar including the microphone test sequences for measuring microphone self noise, microphone substitution, frequency response and sensitivity, and open loop. Additionally, we offer the sequences featured in this seminar measuring digital MEMS microphones and microphone intermodulation distortion in our sequence library for download. Along with the sequences featured in this seminar, our sequence library is full of additional pre-written sequences for basic microphone measurement.

More about advanced microphone measurements

Check out our main page on Microphones, which includes links to test sequences, relevant products and more.

Simulated Free Field Measurements Without an Anechoic Chamber

In this online seminar, Steve Temme explains how to use simulated free field measurements to provide accurate free-field measurements across the entire audible frequency range without an anechoic chamber. This enables measurements that would usually be made in an anechoic chamber to be made in a regular lab or even home office – a valuable capability when so many are currently working from home.

This measurement method, which has been available in SoundCheck since 2001, measures the near-field response at low frequencies and the time-windowed far-field measurement at higher frequencies, and splices them together to provide the response over the entire frequency range.

This seminar explains the acoustics and mathematics behind this method, demonstrates the test procedure with the pre-written (and available free of charge) SoundCheck test sequence, and show how the results correlate to measurements made in an anechoic chamber.

Seminar topics include:

  • Discussion of sound paths and reflections and explaining the mathematic and acoustic principles behind simulated free field measurement techniques
  • Test set-up that can be used to measure this
  • Demonstration of the “Splice” sequence and measurements in SoundCheck
  • Correlation to results made in an anechoic chamber and manufacturer’s published data

Presenters: Steve Temme
Duration: 31 Mins

Resources for simulated free field measurements

Steve Temme and Christopher Struck authored a whitepaper for the AES on simulated free field measurements, available as PDF for further reading.

Our pre-written sequence demonstrated in this seminar for measuring the anechoic response of a loudspeaker without an anechoic chamber, or “Splice” sequence, is available for download from our sequence library

Check out our main page on Loudspeakers and Microspeakers, which includes links to test sequences, relevant products and more.

Advanced Microphone Test Part 1

Listen’s Support Manager, Steve Tatarunis, discusses some of the more advanced aspects of microphone test. This is an expansion of material covered in the Basic Microphone Testing webinar. This seminar is of interest to anyone testing microphone characteristics, both in an R&D and production line environment. This is part one of two in our advanced microphone measurement seminar series, with part two also available on our website. The tests featured in this seminar can be used both at component level, whether selecting microphones for devices or component QC, or these tests can be performed on finished products like smartphones, smart speakers, and more.

Seminar topics include:

  • Demo of microphone test methods substitution, equalized source, and transfer function in SoundCheck
    • How to calibrate for these measurements
    • What are the trade-offs?
  • Advanced microphone test measurements
    • Polar plot
    • Self noise and signal to noise
    • Open loop
    • Active/passive noise rejection

Presenters: Steve Tatarunis
Duration: 63 Mins

Advanced microphone test resources

SoundCheck comes with many pre-written sequences including the sequences demonstrated in this seminar including the microphone test sequences for measuring microphone self noise, microphone substitution, frequency response and sensitivity, and open loop. Additionally, we offer the sequences featured in this seminar microphone polar plot measurements with the new MDT-4000 turntable and open loop microphone test in our sequence library for download. Along with the sequences featured in this seminar, our sequence library is full of additional pre-written sequences for basic microphone measurement.

More about advanced microphone tests

Check out our main page on Microphones, which includes links to test sequences, relevant products and more.