Report of the Meeting of the SC-04-04 working group on microphone measurement and characterization of the SC-04 subcommittee on acoustics, held in New York, NY, US, 2019-10-16
Vice-chair David Josephson convened the meeting, patent policy read, introduction of attendees, agenda approved, report of previous meeting held 2018-10 in New York approved.
In attendence were D Josephson, J Brito *, E Brixen, H Wittek, S Dorsey, S Flock, O Moesmann, C Struck, H Singleton, R Cabot.
Open projects
AES42-R Review of AES42-2010: AES Standard for Acoustics - Digital interface for microphones
AES-42R is in the comment period after a minor revision to address comments received early in the revision cycle. Rich Cabot reported that no further comments had been submitted.
AES-X085 Detailed Professional Microphone Specifications
AES-X085 remains principally a vehicle for formulating AES advice to IEC for revision of the microphone standard IEC 60268-4. There was some discussion about restating the “maximum SPL” specification since there is no standardized method for defining this parameter. It is important not only for users who want to know the maximum sound handling capacity of a microphone, but also for builders of wireless microphone systems to know the maximum signal that can be expected at the transmitter input. Eddy Brixen will summarize the current method used by DPA and perhaps consensus can be reached on a method everyone can use.
There is no progress to report on the wind noise round-robin test. It is understood that the sample microphones provided by one manufacturer are at the lab of another manufacturer where testing is to take place. Initially there were about ten labs interested in participating. Please respond to the reflector if your company still wants to do this work.
AES-X230: Control Data for Microphones
AES-X230 may no longer be required given the progress on AES70 and the lack of development in AES42. Rich Cabot will find out from SC-02-12 whether further advice is needed.
New projects:
A new project concept was introduced by David Josephson, to develop an information document on the physical and electrical interface for interchangeable handheld wireless microphone capsules, and wireless microphone belt-pack transmitters. There was some skepticism that manufacturers would be interested in formally documenting these parameters. Members who make wireless microphones are invited to respond to this email reflector with an indication of interest.
Liaisons:
There is no liaison work now underway. There is not a revision scheduled for IEC 60268-4 or 61938, the two standards where SC-04-04 has provided experts in the past.
New business:
There was no new business.
The next meeting will be held in Vienna, Austria 2020-05, in conjunction with the AES 148th convention.
