SA-10 D4 Classic

The SA-10 Classic pairs 1000W RMS handling with 19mm of one-way excursion in a 10-inch format, which is a lot of output from a woofer that fits a small box. A cast aluminum frame anchors a custom 2.5-inch voice coil, a double-layered Nomex spider, and an SPL competition-grade paper cone, so alignment holds under hard, repeated travel.

A large aluminum Faraday ring sits in the motor to cut distortion and keep response even as excursion rises, and low-distortion motor construction plus high-temperature voice coil wire handle the thermal load of sustained power. Spring-loaded terminals make wiring quick, and stitched-on XL tinsel leads stay tied down rather than slapping the cone at full stroke.

Dual 4-ohm coils wire to 2 ohm or 8 ohm, which is the configuration to pick when you are running two woofers or an amplifier that prefers a higher load. The design works in nearly any enclosure: 1.0 cu ft ported with 15 sq in of port tuned to 35 Hz for maximum output, 0.5 cu ft sealed for tighter response where space is scarce, or a 4th-order bandpass with a 0.4 cu ft sealed side and 1.2 cu ft ported side. At 6 inches of mounting depth behind a 9.25-inch cutout, it fits shallow trunk boxes and under-seat truck enclosures.