IEEE Std 219-1975 PDF

Full title and description

IEEE Std 219-1975 — IEEE Recommended Practice for Loudspeaker Measurements. This document provides recommended practices and standardized methods for measuring physical steady‑state characteristics of loudspeakers and loudspeaker systems, including test conditions, measurement setups, and presentation of results.

Abstract

IEEE Std 219-1975 (revision of IEEE Std 219-1961) defines recommended procedures for objective measurement of loudspeaker performance. It covers measurement environments (anechoic and reverberant), reference axes and distances, stimulus signals and measurement techniques, and the preferred ways to report frequency response, sensitivity, impedance, distortion, and related parameters so that product characteristics can be compared reproducibly.

General information

• Status: Inactive / Withdrawn (IEEE inactive-withdrawn standard).
• Publication date: 24 November 1975.
• Publisher: Institute of Electrical and Electronics Engineers (IEEE).
• ICS / categories: 17.140.50 (Electroacoustics); 17.140.01 (Acoustic measurements and noise abatement).
• Edition / version: IEEE Std 219-1975 (revision of IEEE Std 219-1961).
• Number of pages: 22 pages (typical published PDF length).

Scope

This recommended practice applies to loudspeakers and loudspeaker systems and is intended for objective, steady‑state laboratory measurements. It specifies preferred measurement conditions (geometry, distance, mounting), stimulus signals (sinusoids, swept tones, specified noise), measurement parameters (frequency response, sensitivity, rated impedance, power handling, harmonic distortion), instrumentation and calibration considerations, and conventions for reporting results so that different test laboratories and manufacturers can compare data consistently.

Key topics and requirements

• Definitions and terminology for loudspeaker measurement and presentation of results.
• Specification of measurement environments: anechoic, semi‑anechoic and reverberation conditions and their appropriate uses.
• Reference axis, mounting and recommended microphone positions and distances for on‑axis and off‑axis measurements.
• Required stimulus signals and measurement procedures for frequency response and sensitivity (e.g., swept‑sine, pink noise).
• Methods for measuring electrical impedance and nominal/rated impedance.
• Procedures for measuring distortion (harmonic and intermodulation) and reporting levels relative to input power.
• Recommended conventions for reporting power ratings, power handling, and thermal considerations.
• Presentation format for data (plots, tabulated values, reference conditions) to ensure reproducibility and comparability.

Typical use and users

Used by loudspeaker and audio equipment manufacturers, product test laboratories, acoustic and electroacoustic engineers, quality assurance teams, and research groups needing standardized, repeatable objective measurements of loudspeaker performance. Also useful for specifications writers and procurement engineers comparing loudspeaker products.

Related standards

Key related documents include the earlier IEEE Std 219-1961 (the standard revised by the 1975 edition), the IEC/TC 100 series on sound system equipment (notably IEC 60268-1 general and IEC 60268-5 for loudspeaker measurement and characteristics), and later national and international electroacoustics measurement standards that updated or replaced older practices.

Keywords

loudspeaker measurements, loudspeaker, electroacoustics, frequency response, sensitivity, impedance, distortion, power handling, anechoic chamber, measurement procedures, reference axis

FAQ

Q: What is this standard?

A: IEEE Std 219-1975 is a recommended practice titled "IEEE Recommended Practice for Loudspeaker Measurements" that defines standardized, objective methods for measuring loudspeaker characteristics.

Q: What does it cover?

A: It covers measurement environments and setups, stimulus signals, procedures for measuring frequency response, sensitivity, impedance, distortion and power handling, and conventions for presenting results so measurements are reproducible and comparable.

Q: Who typically uses it?

A: Loudspeaker and audio equipment manufacturers, independent test laboratories, acoustical and electroacoustic engineers, QA and R&D teams, and anyone needing standardized objective loudspeaker data.

Q: Is it current or superseded?

A: IEEE Std 219-1975 has been made inactive/withdrawn by IEEE. Its content has been superseded in practice by later and more widely adopted international electroacoustic standards (for example the IEC 60268 series) and newer measurement practices.

Q: Is it part of a series?

A: Yes — it is part of IEEE's recommended practices on audio and electroacoustics (it is the 1975 revision of IEEE Std 219-1961) and is related to the broader IEC/ISO electroacoustics standards series (IEC 60268 and related parts).

Q: What are the key keywords?

A: Loudspeaker measurements, electroacoustics, frequency response, sensitivity, impedance, distortion, anechoic, measurement procedures.