Audioengine S8 Powered Subwoofer 250W 8-Inch Review (2026)

What it is

The Audioengine S8 is a self-powered subwoofer built around a single 8-inch long-throw, down-firing woofer housed in a roughly cube-shaped cabinet measuring about 11.25 inches on each side. Its amplifier is a class AB design rated at 125 watts RMS continuous, with a peak AES output figure of 250 watts, a common way manufacturers express both the sustained and short-burst power a subwoofer amplifier can deliver. It accepts input through a 3.5mm minijack, stereo RCA, or a dedicated RCA LFE connection, covering most ways a receiver, preamp, or powered speaker pair might feed a subwoofer. The unit runs on 110-240V power, so it can operate on either US or international mains voltage without a separate converter.

Power and output figures

Audioengine's own tech specs list 125 watts RMS as the continuous rated output, with 250 watts describing the peak AES figure the amplifier can reach for short bursts, a distinction worth understanding since marketing copy tends to lead with the larger peak number rather than the sustained one. In practice, the continuous rating is the more meaningful figure for how the subwoofer performs during normal listening, while the peak number reflects headroom for brief musical transients like a bass drum hit. Frequency range is specified at 27Hz to 180Hz within plus or minus 1.5dB, and total harmonic distortion is rated under 0.05 percent at all power settings, both reasonable figures for a compact subwoofer in this size class.

Controls and setup

The S8 includes an adjustable crossover, with Audioengine specifying a range of roughly 50Hz to 130Hz, letting you tune where the subwoofer hands off to your main speakers depending on how low those speakers extend on their own. A phase control covering 0 to 180 degrees is also included, useful for aligning the subwoofer's bass output in time with the main speakers to avoid cancellation at the crossover point. Standby power draw is rated at 8 watts, and the unit includes an automatic signal-sensing feature common on modern powered subs that wakes it from standby when it detects an incoming signal. Signal-to-noise ratio is specified above 95dB typical A-weighted, a solid figure for keeping self-noise out of quiet passages.

Size and placement

At roughly 11.25 inches per side and about 28 pounds, the S8 is compact enough to tuck under a desk, beside a rack, or in a corner of a smaller room without dominating the space the way a larger 10 or 12-inch subwoofer cabinet would. The down-firing driver orientation is intended to couple bass energy with the floor, which can work well on hard flooring but may sound different depending on carpet thickness or whether it sits on a rug. This compact footprint comes at a price premium compared with 8-inch subwoofers from more budget-focused brands, reflecting Audioengine's positioning as a premium desktop and small-room audio company rather than a value subwoofer specialist.

Who it suits

The S8 is a natural match for anyone already running Audioengine's powered bookshelf speakers on a desk or in a smaller listening room and wanting to add low-end extension without a bulky cabinet. Its size and Class AB amplifier suit near-field and small-room use rather than filling a large open living room with bass, where a bigger driver and higher continuous wattage sub would have an easier time. Buyers focused purely on maximum bass output per dollar will find larger 10 or 12-inch subwoofers from budget-oriented brands deliver more raw output for the price, but the S8's compact size, quieter standby power draw, and build quality are the tradeoff for that premium. It suits a turntable-based desktop or small room hi-fi setup well.

Frequently asked questions