Opens in a new tab

AES E-Library

← Back to search

Convention Paper

Maximum Efficiency of Direct-Radiator Loudspeakers

Authors: Keele, Jr., D. B. (Don)

AES Convention 91 · Paper 3193 · October 1991

Abstract

The Thiele/Small method of low frequency direct-radiator loudspeaker system analysis neglects the radiation impedance components in the equivalent electric network model. When these components are included some surprising results are evident. Due to the definition of efficiency widely used in direct-radiator loudspeaker analysis, the absolute maximum efficiency is limited to 25%. With voice-coil inductance neglected, inclusion of the radiation impedance components transform all responses from high-pass into band-pass functions. Fow low frequencies, the maximum achievable nominal power transfer efficiency is found to be proportional to cone diameter. For a specific diameter, the maximum efficiency depends only on the moving mass to air-load mass ratio. Relationships and graphs are presented which relate the true nominal power-transfer efficiency to the Thiele/Small derived efficiency.

Details

Published in
AES Convention 91
AES Convention
91
Paper number
3193
Publication date
October 6, 1991
Session subject
Loudspeakers
Affiliation
Audio Magazine, Hachette Magazines, Inc., New York, NY ; DBK Associates, Elkhart, IN (See document for exact affiliation information.)
Type
Convention Paper