Theory Audio Design is a loudspeaker manufacturer based in Lake Forest, California, founded in 2018 by Paul Hales. Hales — a longtime loudspeaker designer who previously launched Hales Design Group in 1989 and Pro Audio Technology (PRO) in 2004 — built Theory as a sister brand to PRO, sharing engineering principles and a 7,500-square-foot Experience Center in Orange County. The company applies professional-audio engineering, advanced driver materials, and DSP to products aimed at premium residential, commercial, and live-sound installations.

Theory's catalog centers on architectural and soundbar loudspeakers paired with dedicated DSP loudspeaker controllers. The residential lineup includes the sb25 soundbar family (with sizes intended to match 65", 75", and 85" televisions), in-wall models such as the iw25, in-ceiling models such as the ic5, and weatherproof outdoor variants like the iws12-9. A line of high-output passive subwoofers rounds out home installations, while the SR series — including the SR-212LF, SR-215LF, SR-218LF, and SR-221LF subwoofers — targets sound reinforcement applications.

In 2023 the company launched Theory Professional, extending the brand into commercial and live-sound markets. Both sides of the business share Theory's signature approach of small, modular product families that rely heavily on amplified and unamplified DSP controllers to extract performance from compact enclosures, positioning the brand more in the high-end installed-audio world than the traditional pro-audio touring market.

Theory Audio Design has 8 products cataloged on Equipboard, including Speakers & Accessories and Subwoofers & Accessories.