The meeting was convened by chair S. Hutt.
Present were Steve Hutt, Richard Cabot, Bruce Olson, David Andrews, Rafael Kassier, David Carlstrom, Joel Brito, Steve Thompson, Kommer Kleijn, Filippo Bartolozzi, Pietro Massini, Neil Shaw, Ed Simon, Charlie Hughes, Merlijn van Veen, Pat Dennis, David Robb, David Blore, Mattia Cobianchi, Bob Snelgrove, Geoff Hill, Roger Schwenke, Thomas Lago, John Busenitz, Lon Neumann.
The formal notice on patent policy was read.
The agenda and the report of the previous meeting, held in Dublin, Ireland, 2019-03-21, were approved as written.
Projects assigned to this group but not mentioned here had no action requested or required - see www.aes.org/standards/meetings/project-status.cfm for details.
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.
Status: Reaffirmed in 2017
Discussion: This revision starting on a blank page – much work to do. No major activity since the last meeting.
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.
Status: The first draft by David Murphy is in the repository.
Discussion: IEC 60268-22 is in development and will be monitored for content, publication will be delayed to around December, 2020
Target: Draft fall 2022
AES-X241 AES Standard for Acoustics - End of Line Testing for Production Loudspeaker Drivers
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.
Status: Gathering comments on draft, next stage to consider tolerances.
Discussion notes: John Busenitz and Pietro Massini have set the Characteristics list spreadsheet to Google docs to improve information acquisition. We’re still working on the best way to document with a paper trail. The chair is considering creating an official task group.
AES-X250 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. Status: Developing first draft.
Discussion notes: Task group leaders Merlijn van Veen and Roger Schwenke are leading bi-weekly on-line meetings. Group is making excellent progress developing the draft. Projected Draft goal is on task for mid-late 2020. Post meeting discussion, chair (sh) recommends moving goal target to 2021 to allow call for comments on the draft.
There was no new business.
The next meeting will be scheduled in conjunction with the AES 149th Convention, to be held online in October 2020.