Speech Intelligibility and Listening Effort

Communication and public address systems

High speech intelligibility or poor listening effort are decisive parameters for the quality of communication and public address systems in all situations.

Speech intelligibility is often subject to safety and type-approval requirements like in announcement systems for buildings or in aircrafts. The listening effort is relevant in highly disturbed environments such as in vehicle, when communicating via mobile phone or headset, as well as in all conference scenarios.

Testing, optimization and validation are essential for an optimal user experience, if necessary even the requirement for certification.

Product optimization and certification

Environmental noise may affect the intelligibility of the transmitted speech for all types of speech transmission. Depending on the application, the improvement of speech intelligibility or the reduction of listening effort is decisive. All factors that impact performance of the devices have to be considered for testing:

  • Talker position and movement
  • Listener position
  • Realistic speech
  • Speech and talker dependency
  • Background noise and reverberation simulation
  • Relevant standards

In Focus:

  • Intelligibility
  • Listening Effort
  • Background noise conditions
  • Different user scenarios
  • User behavior
  • Room conditions
  • Approval




Efficient solutions

From vehicle to communication applications and public address systems: With our measurement and simulation solutions, manufacturers determine the right balance automatically and reproducibly between intelligibility, listening effort and speech quality in the laboratory for any application scenario.

They are efficient tools for optimization and benchmarking of devices and configurations, and cover acoustic reality as well as user behavior.

The implementations of the procedures are standard-compliant:


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Relevant Products

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