Report of the meeting of the SC-04-08 Working Group on Measurement and Equalization of sound systems in rooms, held online, 2024-05-22
Chair Peter Mapp convened the meeting.
In attendance were Peter Mapp, Richard Cabot, Bruce Olson, David Prince, Brian Long, Charlie Hughes, David Bialik, Eddy Brixen, Joel Brito, Tim Habedank, Tom Holman, Brian Vessa.
The formal notice on patent policy was read.
Minutes of previous meeting online, 2023-10-11 were accepted.
AES-X218: Measurement and calibration of sound systems in rooms.
The chair noted that the group had been meeting regularly – once every 2-3 weeks since the Fall of last year and were making some good progress towards providing a survey document.
There was a discussion as to whether the current scope of X218 should be expanded or a new scope proposed as the focus of the group was now towards producing a survey standard rather than an information document. It was agreed that a new scope would be required and that the two current information documents should be published separately to the survey standard. PM noted that he thought they had already been published and not left sitting dormant for the past 3-4 years, noting that he has been out of action for the past 2 years due to surgery, but was now almost fully recovered. He agreed to review and revise these in time for the October standards meetings, with a view to publishing by the end of the year.
It was agreed that the work on the survey standard, which David Prince was leading, would progress. One of the remaining pieces needed was that of intelligibility measurement. PM felt that there was a need for a background information document on intelligibility measurement, as it was not as widely understood as it should be. DP disagreed. After discussion, it was agreed that PM would produce an information document to augment the survey standard and to complete the existing information documents on noise and reverberation time.
DP noted that he felt that X218 and the survey document should incorporate frequency response and impulse response measurement and so would effectively incorporate the work of X219. This approach was agreed and that X219 could therefore be scrapped.
AES-X219: Method of measurement for frequency and impulse response of sound systems in auditoria
As noted above – to be discontinued as a separate project and incorporated into X218
Liaisons
During the discussion of X218, it was noted that TC-BOD had an intelligibility project on audio streaming. It was agreed that this was quite different to the intelligibility measurement of a sound system in an auditorium or room, but useful to know of its existence.
PM noted that SMPTE also had a project on B chain intelligibility running (as well as cinema sound systems and acoustics). Brain Vessa, present at the meeting, was running these and gave a brief description. He also noted that he was unaware of the TC-BOD project.
It was noted that Liaison between committees in general had rather lapsed over the past few years and BCO agreed to review and hopefully improve liaisons.
New Projects
No new projects were proposed.
New Business
After the meeting, PM announced his intention to step down as chair, as he had served for over 10 years. David Prince has agreed to step up from Vice Chair to Chair of SC-04-08.
The next meeting will be held online in May 2024, scheduled in conjunction with the AES 156th Convention.
