The Official Website of D.B. Keele, Jr. | Loudspeaker Engineering & CBT Arrays Inventor | Audio Magazine Reviewer

36. Maximum Efficiency of Compression Drivers

AES Convention: 117 Paper Number:6193
Publication Date: 2004-10-06

Small-signal calculations show that the maximum nominal efficiency of a horn loudspeaker compression driver is 50% and the maximum true efficiency is 100%. Maximum efficiency occurs at the driver`s resonance frequency. In the absence of driver mechanical losses, the maximum nominal efficiency occurs when the reflected acoustic load resistance equals the driver `s voice-coil resistance and the maximum true efficiency occurs when the reflected acoustic load resistance is much higher that the driver’s voice-coil resistance. To maximize the driver `s broad-band true efficiency, the Bl force factor must be increased as much as possible, while jointly reducing moving mass, voice-coil inductance, mechanical losses, and front airchamber volume. Higher compression ratios will raise high-frequency efficiency but may decrease mid-band efficiency. This paper will explore in detail the efficiency and design implications of both the nominal and true efficiency relationships including gain-bandwidth tradeoffs.

Click to Browse
Keele, Jr., D.B. (Don); 2004; Maximum Efficiency of Compression Drivers [PDF]; Harman International, Northridge, CA; Paper 6193; Available from: https://aes2.org/publications/elibrary-page/?id=12850

Don’t worry about people stealing your ideas. If your ideas are any good, you’ll have to ram them down people’s throats.

Howard Aiken, IBM engineer
NOTICE!
Please note that these materials are presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author’s copyright. These works may not be reposted without the explicit permission of the copyright holder
Note that one has to respect the copyright and to ask permission to the copyright owner if one wants to print or use a paper.