AES2-1984 (r2003) AES Recommended Practice Specification of Loudspeaker Components Used in Professional Audio and Sound Reinforcement Published by Audio Engineering Society, Inc. Copyright ©1984 by the Audio Engineering Society Abstract This document is a recommended practice for describing and specifying loudspeaker components used in professional audio and sound-reinforcement systems. These components include high- frequency drivers, high- and mid-frequency horns, low-frequency drivers, and low-frequency enclosures. For drivers, specifications are given for describing frequency response, impedance, distortion, and power handling. For horns and enclosures, specifications are given for describing directional characteristics and additional pertinent performance data. For all components, specifications are given for describing necessary physical and mechanical characteristics, such as hardware, mounting data, size, and weight. Appendices supporting the text give guidelines for making proper free-field measurements, sizing of baffles for low-frequency driver measurements, a method for producing the specified noise signal used in power testing, and a summary of required information. An AES standard implies a consensus of those directly and materially affected by its scope and provisions and is intended as a guide to aid the manufacturer, the consumer, and the general public. The existence of an AES standard does not in any respect preclude anyone, whether or not he or she has approved the document, from manufacturing, marketing, purchasing, or using products, processes, or procedures not in agreement with the Standard. Prior to approval, all parties were provided opportunities to comment or object to any provision. Approval does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the standards document. This document is subject to periodic review and users are cautioned to obtain the latest edition.