Monacor SPX-31M 3'' Full Range Driver

The Monacor SPX-31M is a compact 3-inch full-range driver, engineered to deliver clear and natural sound reproduction in space-constrained applications. As a broadband subwoofer, it excels at providing balanced audio across the frequency spectrum, making it an ideal choice for DIY speaker projects, multimedia systems, or small-scale public address installations where high-quality sound is required without the need for a separate tweeter.

This driver features a paper cone and a copper voice coil, which together ensure warm, articulate audio with minimal coloration. With a nominal impedance of 8 ohms and a sensitivity of 86 dB SPL at 1 metre per 2.83 volts, it offers efficient performance suitable for low-to-moderate power amplifiers. The total Q factor (Qts) of 0.58 indicates a well-damped response, allowing for versatile enclosure designs, including sealed or ported cabinets. The maximum linear excursion (Xmax) of 1.1 mm supports controlled bass output, while the DC resistance (Re) of 6.4 ohms ensures stable operation.

Technical specifications include a mounting hole diameter of 4.3 mm, a baffle cut-out diameter of 71 mm, and a depth of 55 mm, making it easy to integrate into compact enclosures. The four mounting holes simplify installation. Whether for a custom bookshelf speaker or a retrofit project, the SPX-31M delivers reliable, full-range audio performance in a small footprint.