Monitor Audio Radius 4G Three Bookshelf Speakers

The Monitor Audio Radius 3 is a high-performance mini-monitor delivering precise, high-fidelity sound for TV, film, music, gaming and multi-room applications, including discreet commercial installations. Featuring a 4.5-inch C-CAM driver with RST III geometry and a 25mm C-CAM Gold Dome tweeter, each powered by its own optimised motor system, it combines impressive sonic performance with exceptional versatility, supporting desktop, floor-stand or wall-mount installation.

Features

• Compatible with FIX-M wall bracket
• Compatible with the Radius Desk Pad and Floor Stand
• Finishes available: Satin White, Gloss Black

C-CAM, RST III Cone

Lightweight, strong and more rigid than conventional materials, C-CAM remains the staple driver cone choice for all Monitor Audio speakers and works pistonically to deliver impressive levels of fidelity, now with an evolved RST cone geometry that reduces breakup and resonances.

RST III Bass/Mid Driver

A powerful motor system sits behind the lightweight and rigid C-CAM cone. Coupled with an optimised surround, spider design and increased voice coil diameter, it enables control over deep bass performance, reducing distortion for punchier, more precise bass.

Through-Bolt Driver Bracing

Through-Bolt technology allows the drive units to be securely braced to the rear of the cabinet and tightened to a specific torque to ensure the drive unit and cabinet remain structurally strong, removing unwanted chassis resonances.

Cabinet Design

Monitor Audio is world renowned for the quality and craftsmanship of its cabinetry. Radius Series 4G continues its leadership in this area with beautifully engineered cabinets that present modern satin-painted finishes for discreet applications.

C-CAM Gold Dome Tweeter

Since 1982, Monitor Audio’s gold dome tweeter has continuously been refined. A precision instrument, the combination of incremental changes over four decades has ensured it delivers crisp high frequencies with ultra-realism, clarity and detail.

Crossover Design

Hours of listening and carefully curated component selection have enabled Radius Series 4G crossovers to undergo extensive measurement and refinement to ensure the purest possible signal transfer.

HiVe II Ports

The High Velocity II port (HiVe II) design reduces turbulence and supports airflow acceleration within the port, allowing for fast, powerful bass and greater transient response.

RST III Driver & Motor System

The RST III C-CAM cone and motor system in the Radius 4G represents a significant evolution in Monitor Audio’s metal cone and driver technology. The bass/mid drivers have undergone full FEA optimisation, improving driver surround, spider and chassis design to reduce breakup and resonances.

With larger magnets, an improved voice coil and enhanced venting, it delivers greater control, reduced distortion and improved dynamic range. Complementing this is the C-CAM Gold Dome Tweeter with an optimised UD Waveguide, ensuring smooth, extended high frequencies, precise dispersion and seamless integration with the RST III driver. The result is a speaker that offers remarkable clarity, punch and immersive high-fidelity performance in a compact, versatile form.

HiVe II Port Technology

The refined HiVe II ports on Radius 4G are engineered to deliver cleaner, faster airflow, reducing turbulence and minimising unwanted chuffing. On the Radius 3 models, the ports have been enlarged by 50% compared to the previous generation, further enhancing smooth airflow and delivering tighter, more controlled bass performance.

C-CAM Gold Dome Tweeter

Complementing the C-CAM RST III Bass/Mid Driver, Radius 4G features Monitor Audio’s refined, fully vented C-CAM Gold Dome Tweeter with an optimised UD Waveguide. Now engineered with an external magnet system and a vented former, the design achieves true full venting, eliminating resonance paths from both the dome and surround.

The tweeter, formed from a single piece of ceramic-coated aluminium/magnesium, delivers exceptional rigidity, low distortion and a fast, precise high-frequency response with outstanding clarity and openness. The UD Waveguide ensures smooth, extended highs, controlled dispersion and seamless integration with the RST III driver, resulting in remarkable clarity, punch and immersive high-fidelity performance in a compact form. The gold dome remains a hallmark of Monitor Audio’s metal-driver expertise.

Radius Series 4G Crossover Design

The Radius 4G features a carefully engineered crossover, optimised to deliver seamless integration between the C-CAM Gold Dome Tweeter and RST III driver. Precision components ensure a smooth, balanced frequency response, tight imaging and coherent sound, allowing the speaker to reproduce music and dialogue with clarity, impact and true high-fidelity accuracy.

Specifications

Model:	Radius 3
System Format:	2-Way
Sensitivity (2.83V @ 1m, Free-Field):	84 dB
Sensitivity (2.83V @ 1m, Installed):	N/A
Recommended Amplifier Power (RMS, Music Signal):	75–150 W into 4 Ohms40–75 W into 8 Ohms
Continuous Power Handling (CTA 426-B):	75 W
Nominal Impedance:	8 Ohms
Minimum Impedance (20 Hz to 20 kHz):	4.0 Ohms @ 250 Hz
Drive Unit Complement:	1 × 4½" (115 mm) RST III bass-mid driver1 × 25 mm (1") C-CAM Gold Dome tweeter
Frequency Response, Free-Field (-6 dB):	57 Hz
Frequency Response, In-Room (-6 dB):	44 Hz
Maximum Peak SPL (AES75, Z-Weighted):	107 dB
Bass Alignment:	Ported
Port Tuning Frequency:	53 Hz
Crossover Frequency:	LF/HF: 2.7 kHz
External Dimensions With All Accessories Fitted (H × W × D):	255 × 150 × 201 mm(10 1/16 × 5 7/8 × 7 15/16 in)
Available Finishes:	High Gloss Black, Satin White
Sold As:	Pair
Weight (Each):	3.7 kg (8 lb 3 oz)