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.