Fine Tunes #2 Letters

A Letter in response to Fine Tunes #2 appeared in November 1998:

Editor: Jonathan Scull's "Fine Tunes" column in the August issue of Stereophile (p.63) contains a reference to an Audio Engineering Society (AES) standard listening room. The reference is incorrect in attributing such a room to the AES. The error appears to have come from the website of a manufacturer, who has since corrected his error.

AES has, at this time, only one standards publication showing a listening room. AES20-1996, "AES Recommended Practice for Professional Audio—Subjective Evaluation of Loudspeakers," contains only sets of minimum and maximum distances for the listening arrangement. It does not contain a "standard listening room," and, in fact, the reports of the AES Standards Committee (AESSC) WG-07 Working Group on Listening Tests tend to deprecate such a standard room. Standard listening rooms are described in standards of the International Telecommunications Union; however, they are specifically intended for the evaluation of broadcast monitoring equipment. International Electrotechnical Commission technical report IEC 60268-13 does describe a reference room size (which differs considerably from the room in the article). However, the report is not a standard.

The website that Stereophile referenced drew some of its content from an AES convention paper preprint. AES preprints, as disclosed on their covers, are not peer-reviewed, nor do they in any way represent the views of the AES. All views of the AES on standardization issues are expressed only by the AESSC.

Interested persons should obtain AES20-1996. This standard is a set of recommendations for subjective evaluation of high-performance loudspeaker systems. It expresses the belief that, for certain audio components, including loudspeakers, subjective evaluation is a necessary adjunct to objective measurements. It recognizes the strong influence of listening conditions, program material, and the individuality of evaluators. The document seeks, therefore, to assist its user in avoiding testing errors rather than to attempt the establishment of any single correct procedure.

Directly and materially affected persons may also wish to join the WG-07 working group, which developed AES20. To become a member of the working group, follow the procedures in the "Bulletins and Quick Guides" link at the AES website.—Dan Queen, AES Standards Manager