Tag Archive for: workshops

Seminars in UK and Germany: The Challenges of Testing Speech Controlled Audio Systems

smart_speakersYour devices got smarter. Did your test system?

Learn how to implement open loop tests for both playback and recording in a range of devices including smart speakers, automotive audio, robots, IoT devices and more in this practical half-day seminar.

Open loop testing (testing devices where inputs and outputs are independent) enables many types of smart devices and their components to be tested in various formats and situations including:

  • Smart speakers, smart watches and other smart devices
  • Microphone arrays
  • Speech recognition systems with microphones
  • In-vehicle audio systems
  • Audio devices/systems with no physical inputs or outputs
  • Testing in noisy environments

We explain how to measure the same parameters as traditional loudspeakers, discussing such challenges as injecting and extracting response signals, time delays, and triggering the system using voice commands. We also demonstrate how to measure microphone array performance, speakerphone performance and more. Course content includes:

  • Stimulating and capturing responses from a device where you don’t have direct access to the microphone or speaker (open loop testing).
  • Delays, asynchronous stimulus / acquisition, and working with the ‘cloud’
  • Testing with real world signals such as speech and music, and how to analyze results from these test stimuli
  • Voice Recognition – key word spotting, wake word testing, directionality, and the effect of background noise on voice recognition performance
  • Telephony – testing smart speakers for hands-free calling

There is no charge for this one-day seminar and lunch will be provided. Space is limited, so please RSVP today.


Locations and Dates:

PrintUK: Tuesday Sept 25th, Sharnbrook Hotel, Bedford, England. The Sharnbrook Hotel, Park Lane (off A6), Sharnbrook Bedfordshire MK44 1LX. Note: If you need to stay here overnight, tell them you are with the ACSoft group to take advantage of a discounted rate.


PrintGermany: Thursday Sept 27th, NH München Ost Conference Center, Einsteinring 20, 85609 Aschheim, Germany.



Full Agenda (9am-4.00pm)

  • Introduction to Open Loop Testing
    • What is it?
    • What Kinds of Analysis Can Be Done?
      • Classic Acoustic Testing: Frequency Response and Distortion
        • Stimulus Signals
        • Distortion Methods: THD, THD+N, Rub & Buzz (Squeak & Rattle), Perceptual Rub & Buzz, Non-Coherent Distortion
    • Mixing Digital and Analog Units
    • Capturing Signals Asynchronous to the Stimulus
    • Dealing with Triggering, playback and recording Delays, digital clock Resampling, and corresponding Frequency Shift
  • Open Loop Applications for Playback
    • Smart Devices
      • Frequency Response and Distortion
      • Directionality
    • Automotive
      • 6 Mic Tree for Audio Tuning
      • Distortion methods
      • HATS for Impulse Response Testing @ seated position
  • Networking Lunch
  • Open Loop Applications for Recording
    • Smart Devices
      • Frequency Response and Distortion
      • Voice Recognition
      • Directionality
    • Automotive
      • Frequency Response and Distortion (general and to ITU P.11xx)
      • SNR placement study
      • Impulse Response function from HATS mouth -> microphone
      • Directionality
  • Handsfree Communications
    • Terminology for Handsfree Communications
    • Introduction to Telephony Metrics
  • GRAS Product Overview
    • Choosing the right microphone for your application (far field vs near field vs unconventional environments)
    • When to use a Mouth Simulator vs Head and Torso Simulator for testing


Steve Temme – Listen, Inc.