Yamaha SW-3 Active Servo Subwoofer — 10″ Woofer | Air Woofer Tec

The Yamaha SW-3 is a serious, beefy powered subwoofer built around Yamaha’s proprietary Active Servo Technology — a genuinely clever amplifier-and-speaker feedback system that delivers deep, accurate bass well below what a conventional subwoofer of similar size can achieve.

Active Servo Technology works by coupling a negative-impedance output drive amplifier with a Helmholtz resonator port design — the “Air Woofer” opening in the cabinet. The amplifier continuously monitors and corrects the driver’s motion, reducing distortion and extending low-frequency linearity well beyond the driver’s unassisted capability. The result is tight, controlled bass that integrates naturally with main speakers rather than the bloated, one-note bass that plagues lesser subwoofers. Yamaha rated the SW-3’s frequency response down to 25 Hz (-10 dB) — genuinely deep extension for a sub of this era and price class.

The 100-watt amplifier drives a 25cm (9-13/16″) cone woofer in a solidly built, substantial cabinet. Controls are practical and well-considered: a continuously variable high-cut filter (50–150 Hz at 24 dB/octave) allows precise blending with virtually any main speaker system, an independent volume control sets the level balance, and an Auto Power On/Off function senses incoming signal and powers the sub up and down accordingly. Both speaker-level (Input 1) and line-level (Input 2) inputs are provided, along with speaker-level output pass-through terminals for connecting main speakers — making the SW-3 compatible with nearly any amplifier or receiver regardless of whether a dedicated subwoofer output is available.

This unit is in very good condition and has been thoroughly inspected and tested to confirm full functionality.

Type: Active Servo Processing powered subwoofer
Driver: 25cm (9-13/16″) cone woofer
Amplifier output: 100W (5Ω)
Frequency response: 25 Hz – 200 Hz (-10 dB)
High-cut filter: 50–150 Hz, 24 dB/octave (continuously variable)
Inputs: Speaker-level (Input 1, 4.7kΩ); line-level RCA (Input 2, 10kΩ)
Output: Speaker-level pass-through terminals
Auto Power On/Off: Yes
Power consumption: 130W

Dimensions: (Width x Height x Depth) 14.5 x 18.1 x 15.2 inches (368 x 460 x 386 mm)
Weight: 38.3 lbs (17.4 kg)

A capable, well-engineered powered subwoofer in very good condition — Yamaha’s Active Servo Technology delivers genuinely deep, controlled bass that punches well above this sub’s modest footprint.

Backed by Radique Audio’s Bumper-to-Bumper Warranty and our Perpetual Trade-Back Program, you can purchase with confidence.