Theory Professional
Ecoustics
Theory Professional Unveils SR-221.3 Full-Range Loudspeaker at ISE 2026
The SR-221.3, showcased at ISE 2026, features dual 21-inch drivers, four 10-inch carbon-fiber midrange drivers, and a 5-inch ring-radiator compression driver.
This full-range loudspeaker achieves a remarkable 27 Hz–20 kHz frequency response and offers up to ~140 dB SPL with a 170° × 60° coverage pattern.
Theory Professional's SR Series includes eight models, available as passive, active, portable, and install variants, in compact cabinets.
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