Cambridge Audio MSX SUB 300 – 8" Powered Subwoofer

Cambridge Audio MSX Sub 300 – Active Subwoofer

For larger rooms and more ambitious systems, the MSX Sub 300 extends your setup with deeper, more authoritative bass. Designed to partner seamlessly with MSX speakers and to visually complement the wider Cambridge Audio range, it adds weight and scale without overwhelming your space.

• 1 x 8″ Active Driver with 1 x 8″ Passive Radiator
• 300W Active Power Amplification
• 31Hz (-6dB) – 200Hz Frequency Response
• Intelligent DSP
• Variable Crossover (50Hz – 200Hz)
• Variable Phase Control (0 – 180°)
• Low-Level RCA Input with RCA Pass-Through Output
• Auto-On
• Matte Black or Matte White Finish

Highlights & Key Technologies

Greater Output, Consistent Control
A dedicated 300W amplifier delivers greater output and dynamic headroom, ensuring low frequencies remain composed even at higher listening levels — power with control.

8″ Active Driver with Passive Radiator
An 8″ active driver works alongside a passive radiator to move more air efficiently, increasing depth and output while maintaining precision, for confident low-end performance from a compact enclosure.

Digital Signal Processing (DSP)
Integrated DSP manages frequency response and output in real time, maintaining stability and clarity as listening levels rise, so bass remains controlled and articulate even during demanding passages.

Room-Filling Control
Advanced tuning and adjustable controls, including a variable crossover from 50Hz to 200Hz and variable phase control from 0 to 180°, allow precise integration with your system, ensuring the Sub 300 blends seamlessly for balanced surround sound.

Bigger Bass Impact
The Sub 300 delivers deeper, more authoritative low frequencies, giving home entertainment systems the scale and physical presence that film, TV and music demand. Engineered to move more air with ease, it produces richer, more dynamic surround sound that fills bigger rooms confidently, adding weight to explosions, atmosphere to soundtracks and realism to every scene without overwhelming detail, while bringing added substance to music so tracks feel grounded, controlled and engaging.

Built for Larger Spaces
Ideal for more expansive home entertainment setups, the Sub 300 delivers consistent bass performance across the room without distortion or strain. Pair it with the MSX 20 or integrate it into a larger MSX system for greater scale and headroom. Its compact footprint allows flexible placement in corners, beside furniture or within dedicated media spaces, and it also integrates easily into systems that demand higher output and deeper extension.

Cambridge Audio Heritage
Tuned by ear and guided by decades of Cambridge Audio experience, the subwoofer prioritises musical accuracy alongside power.

Refined Premium Finish
A new premium matte finish, designed to match the beauty of Cambridge Audio’s L/R active stereo speakers, allows the subwoofer to look as refined as it sounds in any room. It combines considered proportions with clean lines, allowing it to integrate with your room rather than dominate it, available in refined black or white.

Details & Specifications

DRIVER
1 x 8″ active, 1 x 8″ passive radiator

POWER OUTPUT
300W

FREQUENCY RESPONSE
31Hz (-6dB) – 200Hz

CROSSOVER
Active – variable 50Hz-200Hz

PHASE CONTROL
Variable 0-180°

INPUTS
1 x Low-level RCA pair

OUTPUTS
1 x RCA Pass-through pair

AUTO-ON
Yes

DIMENSIONS (W x H x D)
266 x 315 x 278mm (10.4 x 12.4 x 10.9″)

WEIGHT
7.5Kg (16.5lbs)

FINISHES
Matte Black, Matte White

WHAT’S IN THE BOX
1 x Subwoofer
Power cable
Safety Guide
Quick Start Guide
Registration card