Rythmik Audio is a Texas-based subwoofer manufacturer founded by Brian Ding in 2006. The company specializes in audiophile-grade subwoofers built around its patented Direct Servo technology, a closed-loop feedback system that uses a thin sensing coil on the driver to detect cone motion and continuously correct it against the input signal. Unlike accelerometer-based servo designs, Direct Servo taps directly into the power amplifier's feedback summing point, which the company credits for reducing distortion, producing a more consistent frequency response across driver variability, and enabling adjustable damping and low phase shift in the bass roll-off.

Rythmik sells factory-built subwoofers and DIY kits direct to customers, a model intended to keep prices lower than comparable high-end brands. The lineup spans the entry-level L Series (such as the L12 and LV12M) and the higher-output F/E Series, including sealed models like the F12, F12SE, F12G, and F18 alongside ported designs such as the FV15HP and FV18, with driver sizes ranging from 8 to 18 inches. The company also offers plate amplifiers, raw drivers, and custom-install variants for architectural applications.

Rythmik is generally positioned toward two-channel music listeners and home theater enthusiasts who prioritize accuracy over raw output, with sealed cabinets typically recommended for music and ported configurations for movies. The brand has a long-running presence on enthusiast forums such as AVS Forum and Audioholics, where Ding himself participates in technical discussions, and reviews in publications including Sound & Vision, Audioholics, and Home Theater Hifi have focused on the subwoofers' low distortion and tight transient response.

Rythmik Audio has 3 products cataloged on Equipboard, including Studio Subwoofers.