GRS K-33-4 Subwoofer

The GRS K-33-4 is a precision-engineered 15-inch replacement woofer designed to restore the deep, authoritative bass that Klipsch speakers are renowned for. As a direct drop-in upgrade for many classic Klipsch models, this subwoofer driver breathes new life into your audio system, ensuring you experience every low-frequency detail with power and clarity. Whether you are refurbishing vintage loudspeakers, upgrading a home cinema setup, or building a high-performance DIY subwoofer enclosure, this driver delivers exceptional performance.

Technically, the K-33-4 boasts a high sensitivity of 97 dB (1m/2.83V), enabling efficient and powerful low-frequency output even with modest amplifier power. Its total Q factor (Qts) of 0.52 strikes an ideal balance for sealed and ported enclosures, while the 8.25 mm linear excursion (Xmax) allows for deep, controlled bass without distortion. The woofer features a paper cone for natural sound reproduction, a copper voice coil wire with a DC resistance of 3.52 ohms, and a robust mechanical Q (Qms) of 12.61 for tight, articulate response. With a nominal diameter of 381 mm, a cut-out diameter of 351.8 mm, and eight mounting holes on a 14.65-inch bolt circle, installation is straightforward. This driver is the perfect choice to revitalise your Klipsch speakers with authentic, room-filling bass.