Fundamentals of the 21st Century
Posted July 2011
In The Lab, by William Dudleston
“For many years the listening room has been regarded by speaker designers as the great unknown; a set of variables involving room geometry, absorption coefficients and decay patterns. Designers have attempted almost as many solutions to room problems as there are rooms. Dipolar, bipolar, cylindrical, omni-directional, and highly directional radiators to name a few. Electrostatic, moving coil dynamic, ionic, planar dynamic, thermo- dynamic and even plasmic transducers. Designs that pushed air, reflected air, heated air, and squeezed air. Ah, the “art” of speaker design. While there have been a number of valid acoustic studies over the past 50 years that have dealt specifically with the loudspeaker/ listening room interface, rarely does such work have a significant influence on speaker design. Perhaps speaker designers are just too flamboyant to pay heed to another designer, let alone learn from his mistakes.
The Legacy loudspeaker designs emphasize directivity control. Predictable room radiation patterns. Our strategy is as follows; include low frequency room gain as part of the transfer function and keep early reflections to an absolute minimum. But most importantly we must have a legitimate understanding of the fundamentals regarding room interactions, what I call the Three R’s — REINFORCEMENT, RESONANCE AND REVERBERATION.”