SC-04-03 meeting, Online, 2022-10

Report of the meeting of the SC-04-03 Working Group on loudspeaker modeling and measurement, held online, 2022-10-10.

The meeting was convened by chair G. Hill.

Present were Gerard Elvina, Geoff Hill, Rich Cabot, Bruce Olson, David Robb, Jim Meyer, Griff Ocker, David Prince, Neil Shaw, Steve Hutt, Stefan Irrgang, Kurt Graffy, Brian Vessa, Tim Gladwin, John Busenitz, Stephen Thompson, Peter Massini, Joel Brito, John Woodgate.

The formal notice on patent policy was read.

The agenda and the report of the previous meeting, held in online, 2022-05-02, were approved as written.

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

Open projects

AES1id-R Review of AES-1id-2012 (r2017): AES Information Document for Acoustics - Plane-Wave Tubes - Design and Practice
Scope: To establish, expand, and improve the practice for the design and use of plane-wave tube measurement techniques, as recommended in section 2.2.1 of AES2-1984, "Recommended Practice Specification of Loudspeaker Components Used in Professional Audio and Sound Reinforcement."

Move to reaffirm

AES2-R Review of AES2-2012: AES standard for acoustics - Methods of measuring and specifying the performance of loudspeakers for professional applications - Drive units
Scope: This Recommended Practice establishes a set of primary specifications to be followed by manufacturers in describing loudspeaker components used in professional audio and sound-reinforcement system design.

Due to be reaffirmed 2023, if anyone has any changes or comments these are needed now. We also need to review AES2 - 2012 in light of cross over with AES75. We need to reach out through these minutes for a volunteer to lead this effort on behalf of this subcommittee.

AES-X168 Characterization of loudspeaker systems;
Scope: This document defines a set of characteristics of loudspeaker systems for inclusion in manufacturers' specification documents, and identifies the relevant methods of measurement. It considers loudspeaker *systems* for professional applications. They may be combinations of active and passive sub-systems. It is intended for users and designers of loudspeaker system installations.

This has a target date of 2022. There was a lot of informal feedback a couple of years ago, David Murphy posting an updated draft.

Neil Shaw from SMPTE commented they have a parallel interest in this and would be prepared to cooperate but only as liaison.

It was moved that David Murphy's draft be posted for formal comments.

AES-X241 AES Standard for Acoustics - End of Line Testing for Production Loudspeaker Drivers
Current Scope: This standard specifies parameters and methods of measurement required for end-of-line quality control tests performed on loudspeaker drivers manufactured for automotive, consumer and professional applications. It includes requirements for mechanical setup. It does not consider measurements of loudspeaker systems or multi-driver arrangements.

David Prince has posted a draft of an updated scope; this includes prior work as an appendix. After discussion it was agreed that this has merit, but some questioned whether manufacturers would be willing to disclose some of the information involved freely. It was agreed that such information outlined in the draft could be treated as internally confidential and that publication is not a requirement, rather that it should be seen and understood as an internal audit document to help define best practice.

The chair will send the amended scope to the entire group for comments, a subgroup to be formed to lead this effort, currently comprising David Prince, Peter Massini, Tim Gladwin and John Busenitz.

AES75 AES Standard for Acoustics - Measuring maximum linear peak SPL using noise
Scope: This standard specifies a method for measuring the maximum linear peak SPL of a loudspeaker driver or system. It uses a mathematically derived test signal that effectively emulates the dynamic characteristics of music as a function of frequency as well as its spectral content. The SC-04-03A task group has begun working on methods to spread awareness of the standard.


John Woodgate reported IEC TC100 undergoing a reorganisation at the moment and that he would keep AES informed.

New Projects


New Business


The next meeting will be held online in May 2023, scheduled in conjunction with the AES 154th Convention.

AES - Audio Engineering Society