SC-04-03 meeting report, Warsaw, 2015-05

Report of the meeting of the SC-04-03 Working Group on loudspeaker modeling and measurement of the SC-04 Subcommittee on Acoustics, held in Warsaw, Poland, 2015-05-09

The meeting was convened by chair S. Hutt.

 The agenda and the report of the previous meeting, held in Los Angeles, 2014-10-11, were approved as written.

Projects assigned to this group but not mentioned here had no action requested or required - see for details.

Open Projects:

AES-X168 Characterization of loudspeaker systems

At the Los Angeles meeting, SC-04-03 agreed to suspend AES-X168 pending the release of a new IEC standard, at which time SC-04-03 will re-engage to appropriately address X168.
 J. Woodgate provided an update on the development of updated IEC 60268-5 proposals:

  • • Micro loudspeakers (China) update due October 2015 ,
  • • Systems (CEA), an update is planned for November 2015, though we will ask whether it is possible to move that ahead some weeks so this group can discuss it in October.
  • • W. Klippel's systems draft is in process.

AES-X194 Report on loudspeaker terminology
scope: This report summarises formally-defined terminology currently existing in International standards from ISO and IEC, as well as the AES.
status: Intent to develop the draft.
Discussions: It was agreed that the X194 terminology project is useful particularly in light of non-AES references having inappropriate or erroneous definitions. The chair will begin reflector discussions to break the task into smaller bits in order to develop dialog.

AES-X223: Loudspeaker Driver Correlation Chamber
Replicating non-anechoic loudspeaker driver measurements in different locations is a well known and challenging endeavor due to numerous influences and degrees of freedom. G. Hill and E. Simon have contributed concepts. A generic draft will be presented to the reflector before our October meeting.


ALMA International: Geoff Hill will participate in an ALMA standard meet in the next few weeks and provide feedback.

New Projects:

Program power. Hutt proposed to open a discussion on the definition of “program power”. This is a tricky subject that cannot be defined without discrete knowledge of devices, systems, sources, duration and numerous other factors. IEC and ALMA have definitions, however neither provide clear guidance or procedures. The question is, can we provide a definition and guidance that is pertinemt and useful? Any work SC-04-03 might do in this area is expected to be coordinated with IEC 60268-5.

New Business

J. Woodgate informed us that a Japanese group is looking to develop a measurement method for a vibration transducer applied to a pinna.

The next meeting will be scheduled in conjunction with the AES 139th Convention in New York, NY., US., 29 October to 1 November, 2015.

AES - Audio Engineering Society