Automatic Quality Testing of Loudspeaker Electroacoustic Performance

The electroacoustic performance of loudspeakers can be tested by automatic instrumentation. A battery of tests can be designed to detect most major faults, compare to previously defined limits, and automatically yield a pass or fail indication. The battery may include tests for frequency response, sensitivity, rubbing voice coils, buzzing or rattling structures, loose particles, motor and cone distortion, polarity and impedance. Observations can be made about how each test correlates to audibly perceived quality. Although pass/fail criteria will be different for each type of loudspeaker, general guidelines can be given. The design and implementation of the tests will be described, and examples will be shown for both good and bad loudspeakers.