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New AmpConnect 621 Multichannel, Multifunction Audio Interface

AmpConnect 621

The new AmpConnect 621 is Listen’s next generation multichannel, multifunction, high resolution audio test interface. It is ideal for any application where more than 2 channels are needed, for example, automotive audio, voice-activated device measurements, sound power measurements and measuring devices with multiple speakers such as soundbars and smartphones. With a sample rate of up to 192kHz, it is also a great choice for measuring high resolution devices such as headphones and hearables. Additionally, it includes all the functionality required for audio testing in just one unit, including an amplifier, microphone power supply, line outputs and digital I/O.

AmpConnect 621 features 6 inputs, 2 line outputs and one amplifier output. All inputs offer microphone power (SCM, IEPE and pre-polarized), to accommodate many types of couplers, accelerometers and reference microphones – even the new Brüel and Kjær 5128 high resolution head and torso simulator. Full TEDS support for microphones and accelerometers simplifies setup and calibration by importing the data at the click of a button. The 2 line level outputs plus  a separate 50W amplifier route the output signal to any sources, powered or needing amplification, (e.g. artificial mouth, speakers, headphones, automotive head units). Impedance measurements using the amplifier output, along with output voltage monitoring, are performed entirely internally and do not require using any of the 6 external input channels, leaving them open for other measurements. This, along with digital I/O, simplifies operation as signals are all routed internally with no additional cabling required. The device connects to the computer with a single USB cable; the only additional cables required are those connecting your microphones and DUTs. This all-in-one approach offers excellent ground loop immunity in comparison to discrete components.

The interface has no control knobs on the front; control is entirely through the SoundCheck software interface. This minimizes errors by making it impossible for settings to be accidentally changed. For example, in a production environment, the only way the operator can adjust the settings is by modifying the test sequence, and access to this can be restricted via operator access rights. This helps OEMs ensure test integrity when requiring contract manufacturers or offshore manufacturing facilities to run their test sequences. This is also advantageous for protecting against accidental changes in a laboratory, particularly when multiple people are accessing the same piece of equipment. The front panel features visual indicators for power, input and output level, amplifier channel and level so that overloads, etc. can be clearly identified.

Test deployment is fast with full plug and play functionality. Channel configuration is fully automatic when the AmpConnect 621 is connected to the SoundCheck computer – the user just needs to adjust driver selection and sampling rate if different from the default values. Calibration data is read from TEDS microphones in SoundCheck’s calibration editor, or easily imported from a calibration file. When setting up multiple systems, the AmpConnect only needs to be configured once, and the setup can be duplicated to other test stations; there is no need to re-configure AmpConnect 621 each time.

AmpConnect 621 offers the option to use WASAPI-exclusive mode with Windows 10 audio devices in addition to the more commonly used ASIO drivers. This advanced communication protocol allows SoundCheck to bypass the Windows audio mixer, sending audio streams directly to the device. This results in lower latency and ensures that there is no sample rate conversion behind the scenes. It also enables SoundCheck to put an exclusive lock on the audio interface so that a measurement cannot be disrupted by system sounds which is valuable in highly automated settings. Multiple WASAPI devices can be used simultaneously, and WASAPI and ASIO devices can be combined to increase channel availability.

Like Listen’s other hardware products, AmpConnect 621 is built to last in production environments. The 17” wide x 2-Units (3.5”) high x 11.5” deep rack-mountable unit is rugged with a new fingerprint-resistant matte finish.

 

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Seminar at Sound Hub

Today, Steve Temme presented on how to measure voice activated devices such as smart speakers, hearables and automotive audio, as well as how to use SoundCheck for basic audio measurements at Sound Hub Denmark, the world’s leading audio innovation hub and co-working space.In the morning, he presented the basics of SoundCheck, and taught attendees (many of whom had access to the SoundCheck system at Sound Hub) how to build a test sequence in SoundCheck. recommendations for the equipment used. After lunch, he explained in depth how to test voice activated devices such as automotive infotainment systems, hearables, and smart speakers. These devices are complex to test as they have numerous wired and wireless connections and often contain signal processing, both on the record and the playback side. In this session, he outlined the test configurations, tools and techniques that enable accurate measurement of the audio performance of such devices under the many various real-world conditions in which they are used.

Practical Testing of Voice Controlled Devices

Author: Steve Temme.  Reprinted from the Jan 2020 issue of AudioXpress.

This article discusses tools and techniques that are available to accurately measure the audio performance of voice-controlled and connected devices under the many various real-world conditions they may be used. It covers basic acoustic measurements such as frequency and distortion response, which have always been carried out on conventional wired systems, and the more complex real-world tests that apply specifically to voice-activated devices, along withthe techniques and standards that may be used.
Full Article

 

 

 

 

 

AES Convention– New York – October 16-19, 2019

Although Listen won’t be exhibiting, president Steve Temme will be at the event and will be participating in two product development sessions detailed below.

 

Product Development: PD09 – Does Automotive Audio Need a Systems Approach?

Thursday, October 17, 1:30 pm — 3:00 pm (1E09)

Chair: Roger Shively, JJR Acoustics, LLC

Panelists: John Busenitz, Bose Corporation, Pietro Massini, Ask Industries S.p.A, Greg Sikora, Harman International, Steve Temme, Listen, Inc.

Some component specifications do not translate to good system performance. A good example is resonance frequency. This often does not correspond well to performance characteristics in the automotive environment. Some potential improvements would be low-frequency SPL, or a parameter combination such as Fs/Qts or EBP (Fs/Qes). The system performance goals should drive the transducer component specification. Hence, this workshop will host leading industry experts in automotive audio and test/measurement solutions to discuss pros and cons of component vs. system specifications.

 

Product Development: PD10 – Diagnostics for Production Vehicle Audio Systems

Thursday, October 17, 3:15 pm — 4:30 pm (1E09)

Presenters: Jonathan Gerbet, Klippel GmbH, Steven Hutt, Equity Sound Investments, Steve Temme, Listen, Inc.

Audio systems in production vehicles are known to exhibit vehicle to vehicle performance variance [1]. The root causes of variance can include loudspeaker driver manufacturing tolerance, mounting issues such as missing or misaligned gaskets, or wrong loudspeaker drivers mounted in the system. A diagnostics method to compare actual production vehicle audio systems is defined along with a method for correction and calibration of production vehicle audio systems. The diagnostics procedure may be implemented at production end-of-line, at vehicle distribution center or at a dealer service center in the field after delivery to a customer.

Full AES Schedule

Seminars in China: Smart Speakers and Automotive Audio

The Challenges of Testing Speech Controlled Audio Systems

Your 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 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

Speakers /主讲人: Steve Temme, Listen, Inc. and Peter Wulf Andersen, GRAS.

Date & Locations /时间与地点:

2019年1月15日(Tuesday) – Taipei台北
2019年1月16日(Wednesday) – Shenzhen深圳
2019年1月18日(Friday) – Suzhou苏州

More information and registration

SoundCheck/Mentor A2B for Automotive Audio

mentor_a2bWe are excited to announce that SoundCheck fully integrates with the Mentor A2B interface for testing automotive audio connected via the Analog Devices A2B digital bus. The Mentor Analyzer, which handles the transmission of signal in to and out of the bus, is viewed as an ASIO interface by SoundCheck, enabling SoundCheck to read/write to the device and therefore analyze any transducer connected to the A2B bus. A custom VI permits control of the Mentor A2B interface configuration via SoundCheck. This means that it can be controlled from within a SoundCheck sequence, for example loading configurations and starting/stopping ASIO streams. This makes it an ideal R&D or production line test solution for automotive audio, or for anyone testing transducers connected via A2B bus.

Watch a video demonstration of an automotive audio test using the Mentor A2B interface:

 

Please see our knowledgebase article for download links and installation instructions.

Contact your Listen sales engineer for more information.

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

Presenters:

Steve Temme – Listen, Inc.

 

 

Evaluation of audio test methods and measurements for end-of-line loudspeaker quality control

In order to minimize costly warranty repairs, loudspeaker OEMS impose tight specifications and a “total quality” requirement on their part suppliers. At the same time, they also require low prices. This makes it important for driver manufacturers and contract manufacturers to work with their OEM customers to define reasonable specifications and tolerances. They must understand both how the loudspeaker OEMS are testing as part of their incoming QC and also how to implement their own end-of-line measurements to ensure correlation between the two.

Authors: Steve Temme, Listen, Inc. and Viktor Dobos, Harman/Becker Automotive Systems Kft.
Presented at ISEAT 2017, Shenzhen, China

Full Paper

In-Vehicle Distortion Measurement

Authors: Zarina Bhimani, Steve F. Temme (Listen, Inc.), Patrick Dennis (Nissan Motor Co.).  Reprinted from the 2017 Loudspeaker Industry Sourcebook.

Steve Temme and Patrick Dennis discuss their research exploring test methods that will help determine audible distortion and enable manufacturers to test sound equipment after it is installed

Full Article

 

 

Evaluation of Audio Test Methods and Measurements for End-of-Line Automotive Loudspeaker Quality Control

In order to minimize costly warranty repairs, automotive manufacturers impose tight specifications and a “total quality” requirement on their part suppliers. At the same time, they also require low prices. This makes it important for automotive manufacturers to work with automotive loudspeaker suppliers to define reasonable specifications and tolerances, and to understand both how the loudspeaker manufacturers are testing and also how to implement their own measurements for incoming QC purposes.

Specifying and testing automotive loudspeakers can be tricky since loudspeakers are inherently nonlinear, time variant and affected by their working conditions & environment which can be change dramatically and rapidly in a vehicle. This paper examines the loudspeaker characteristics that can be measured, and discusses common pitfalls and how to avoid them on a loudspeaker production line. Several different audio test methods and measurements for end-of-the-line automotive speaker quality control are evaluated, and the most relevant ones identified. Speed, statistics, and full traceability are also discussed.

Authors: Steve Temme, Listen, Inc. and Viktor Dobos, Harman/Becker Automotive Systems Kft.
Presented at the 142nd AES Convention, Berlin, Germany

Full Paper