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Question 5/12

Question 5/12 – Telephonometric methodologies for handset and headset terminals
(Continuation of Question 5/12)


Multimedia evolution leads to an increase of the audio signal bandwidth as well as spatial audio in the New Generation Networks. Beside the existing narrowband and wideband, fullband is being developed for the next years. Also, telecommunications is moving from monaural towards binaural.

This situation brings new challenges in terms of standardization which need to be covered during the next study period. The extension of the bandwidth also leads to a need of the harmonization of the algorithms aiming to calculate Loudness Ratings and loudness for all bandwidths from narrowband to fullband audio signals. Furthermore, the extension of the operating frequency range of measurement equipment is required.


The following Recommendations/Supplements, in force at the time of approval of this Question, fall under its responsibility:
P.16, P.32, P.48, P.51, P.52, P.53, P.54, P.55, P.57, P.58, P.61, P.64, P.75, P.76, P.78, P.79, P.360, P.380, P.581, P Suppl. 20



Study items to be considered include, but are not limited to:

  • What enhancements in the existing Recommendations P.57, P.58, P.51 and P.79 need to be defined in order to accommodate for the evolution in the frequency range of audio transmissions?
  • Determine what new Recommendations are required in order to address new technologies being developed during the study period.
  • Considerations on how to help measure and mitigate climate change.


Tasks include, but are not limited to:

    • Adaptation of psychoacoustic based loudness algorithms aiming to determine the loudness for all bandwidths ranging from narrowband to fullband audio signals aiming to revise Recommendation P.79.
    • Improvement of the specifications for acoustic frontends, mainly artificial ears, in order to better match an extended frequency range and fit modern earphone devices, aiming to revise Recommendation P.57 and P.58.
    • Investigation of the directivity – including performance behind the lip-plane – as well as extended frequency range of the artificial mouth, aiming to revise Recommendation P.58.
    • Development of artificial noise-fields in laboratory conditions. 
    • Documentation of new capturing techniques for performance evaluation of terminals in artificial noise fields.
    • Documentation of the applicability of ERP/DRP and free field/diffuse field corrections as well as extension to fullband.
    • Investigation of how to aggregate measurements from multiple test positions into an overall measure of transmission performance.
    • Investigate measurement setups for devices that use bone conducting transducers, e.g. hearing aid.

An up-to-date status of work under this Question is contained in the SG 12 work programme



  • P.300 series


  •  3/12, 4/12 and 6/12

Study Groups

  • none

Standardization bodies