The Acoustic Energy AE308 is the dedicated subwoofer for the 300 Series, completing the range alongside the AE300² bookshelf speakers, AE309² floorstanders, and AE307² centre channel. Designed to deliver powerful, controlled bass for both stereo hi-fi and multichannel home cinema systems, the AE308 pairs a 500W RMS Class D amplifier with a 12-inch downward-firing driver in a sealed enclosure, producing deep bass extension down to 26Hz.
Driver and Amplification
At the heart of the AE308 is a 12-inch high-excursion driver constructed from doped and stiffened pulp-fibre paper cone material. The long-throw design allows substantial cone movement for deep bass reproduction whilst the doping and stiffening treatment controls breakup modes. The driver fires downward through the base of the cabinet, using the floor as an acoustic boundary to reinforce low-frequency output. Powering the driver is a 500W RMS Class D amplifier, providing ample headroom for both sustained musical bass lines and transient home cinema effects.
DSP Processing
The AE308 incorporates a DSP module — a first for Acoustic Energy — offering three distinct operating modes selectable via a colour-coded LED button on the rear panel. In Music mode (red), the subwoofer delivers a balanced, accurate response, extending the low frequencies of the main speakers naturally down to 26Hz (±6dB). Movie mode (blue) adds additional impact to aid explosive soundtracks in multichannel AV systems. Impact mode (green) trades outright low-frequency extension for maximum volume and dynamic punch.
Connectivity and Control
The rear panel provides three connection options to suit any system configuration. A dedicated LFE RCA input accepts the subwoofer output from an AV receiver or processor. Stereo line-level RCA inputs connect to a preamplifier or integrated amplifier’s line outputs. High-level stereo binding posts allow connection directly from amplifier speaker terminals, useful for stereo systems without a dedicated subwoofer output. A continuously variable crossover control adjusts the low-pass frequency between 40Hz and 120Hz, while a 0–180 degree phase control ensures seamless integration with the main speakers. An Auto/On switch provides either signal-sensing power-up or continuous operation.
Cabinet Design
The AE308 uses a sealed cabinet design with no ports, ensuring tight, well-controlled bass with a predictable roll-off characteristic. The compact cubic form factor measures just 360 × 360 × 360mm (H × W × D), making it straightforward to position in a room. Carpet-piercing spikes are included for stability on soft flooring, with rubber caps provided for use on hard floors. The Piano Gloss White lacquer finish matches the other 300 Series models.
| Type | Sealed box, downward-firing driver |
| Drive Unit | 12” high-excursion doped and stiffened paper cone |
| Amplifier Power | 500W RMS |
| Amplifier Type | Class D |
| Frequency Response | 26Hz–120Hz ±6dB |
| Crossover Frequency | 40–120Hz (variable) |
| Phase | 0–180° (variable) |
| Inputs | Low-level stereo RCA, high-level stereo binding posts, LFE RCA |
| DSP Modes | Music, Movie, Impact |
| Dimensions (H × W × D) | 360 × 360 × 360mm |
| Weight | 19kg |
| Finish | Piano Black, Piano White, American Walnut |
| Also Available As | Black, Walnut |