• Subwoofers Subwoofers
  • C-CAM drivers C-CAM drivers
  • Mode switch Mode switch
  • 3 EQ settings 3 EQ settings
  • Power 220watts @ 1% THD+N
  • Footprint 330mm x 345mm
  • Driver size 10in
  • Class D Amp Class D Amp


Radius 390 technology
  • 18mm MDF cabinet construction with internal bracing
  • Cool-running 220W Class D amplifier with switch mode power supply (SMPSU)
  • Twin side-firing 10” C-CAM® drivers - one active and one passive ABR  
  • Low pass filter switch – for LFE or Stereo input selection
  • Power switch with ON – Auto- Off/ trigger settings
  • Stereo/ LFE RCA inputs
  • 3 x Pre-set EQ settings – Music/Movie/Impact



System Format

Active sub-woofer system – Auxiliary (ABR) loading. 18mm MDF cabinet

Low Frequency Limit

30Hz (- 6dB)

Upper Frequency Limit

Variable 40 – 120 Hz @ 24dB/Octave

Amplifier Power Output

220 Watts @ 1% THD+N

Amplifier Classification

Class D amplifier with Switch mode power supply (SMPSU)

Bass EQ Switch

Music/ Movie/ Impact

Phase Control

0 & 180 degrees

Auto Sensing

Line Level >3.5mV

Input Level Requirements

Standby after approximately 15 minutes if no signal sensed

Driver Compliment

1 x 10” (250mm) C-CAM® long throw driver
1 x 10” (250mm) Auxiliary bass radiator

Input Impedance

> 20K Ohms

Mains Input Voltage

AC 110 - 120 V ~ 50/60Hz;  AC 220 - 240 V ~ 50/60Hz  (Factory Region Preset)

Dimensions including amp & feet(H x W x D)

348 x 330 x 345mm
(1311/16 x 13 x 129/16 Inches)


Stereo RCA in, LFE in, 12v Trigger in  (3.5mm mono mini-jack)

12v Trigger Input

5 - 12v via 3.5mm mono mini-jack socket

Power Consumption

220 Watts / 0.5 Watts in Standby (ErP approved)

Weight (Unpacked) 

 13.76Kg (30lb 4oz)

Professional reviews

Radius 90

August 2013

New Radius Off To A Good Start!

"The surround field is gapless, effects flow between channels effortlessly and you're immersed in the action."

"Dialogue through the centre channel is clear and communicative."

"We've heard enough bass boxes to know that they can often be the Achilles' heel of 5.1 systems, but not the 390. It displays a potent combination of precision and weight with no fear of bottoming out or losing its grip."

"And the Radius speakers work wonders with music, whether you're playing a CD or listening to a multichannel music Blu-ray. Spin Michael Jackson's Beat It and there's a solid bassline, a great sense of timing and impressive dynamic clout."

Read the full review

Radius 90

January 2014

Return Of The Radius

"Living room-friendly looks and spine-tingling sound quality."

"With towering Jaegers and Kaiju stomping through cities and oceans, this is a movie that demands impact and scale — something this system achieves without batting an eyelid."

"...the clatter of the robot's metal armour and the beast's rasping roars boast remarkable attack and aggression, without sounding bright or synthetic."

"these little speakers display the sort of slam and dynamism you'd expect from larger designs, hitting that sweet spot between excitement and refinement that leaves you feeling entertained but not violated."

"The subwoofer plays a part here, of course; it pummels the room with authoritative bass notes delivered with supreme depth and grip."

"It rumbles away happily during quieter scenes too, lending subtle atmosphere and warmth to voices and background music."

"The 390 forms a tight union with the satellites, resulting in a cohesive soundfield, and one backed up by the sort of snappy steering that Sebastian Vettel would be proud of."

"Idris Elba's nonsense dialogue, meanwhile, is imbued with an almost life-like presence by the Radius 200, with the dual midbass drivers underpinning his gruff English tones."

"And with music material, it's equally good... the R90HT1 demonstrates outstanding timing, agility and detail retrieval."

"One of the best compact 5.1 systems money can buy? Certainly."

Download the full review

Radius R90HT1

February 2014

AV Tech Media Awards 2014/2015: Radius R90HT1

Hi-Fi News, Hi-Fi Choice and Home Cinema Choice have teamed up for the AV Tech Media Awards 2014/2015, naming Monitor Audio the winner in two categories!

Radius R90HT1, our super compact AV system won "Best Compact Speaker System". "This system mixes both eager dynamism and impressive scale with poise and insight."

Read more in the AV Tech Media Awards supplement included with the Awards issues of Hi-Fi News, Hi-Fi Choice and Home Cinema Choice.


October 2014

2014 Accolade Caps another Great Year for Mighty Radius

The stunning verdict in the ‘Best Style Package £1400-£1800’ category means that if you’re upgrading your home theatre sound with this kind of budget, you can’t buy better than the five-star Radius R90HT1 system! Seduced by the ‘punch and precision’ of our stylish space-saving compact, the review reads “the surround field is like an airtight unit, with effects flowing smoothly and consistently between each channel…with price, performance and practicality on its side, the Radius ticks all the boxes.”

Read the full review

Radius 90

December 2013

Latest Radius Gets a Perfect 10

Designer sat/sub speaker systems come and go, but one just keeps getting better. Back in the 90s Monitor Audio’s Radius showed the industry how to blend high performance and glossy good looks with rooms of any size, shape and colour. The latest Radius evolution burnishes a peerless reputation with even better sound and aesthetics as Danny Philips discovered when testing the new R90HT1 system for Trusted Reviews.

As a former ‘What Video’ editor and an experienced freelance tech journalist, Danny’s qualified to place the R90HT1 at the very top of the pecking order with a perfect 10/10 score and a coveted ‘Editor’s Choice’ badge. Citing a big soundstage from small speakers, superb detail and dialogue clarity and gorgeous build quality and design, he says “it’s beautifully made, offers powerful, polished sound quality and looks stunning – pretty much everything we look for in a speaker system. If you have the cash, it’s worth every penny… If you’re looking for a speaker system on a £1,500 budget then stick the R90HT1 on your shopping list pronto. We’ve heard some pretty special speaker systems of late, including the Quad L-ite Plus and the Cambridge Audio Aero, but the Radius trumps them all”.


Read the full review

Radius 45

September 2013

New Radius launches with five stars

The next generation of Radius has arrived, complete with new models, greater versatility and higher, wider, deeper sound. The eight-strong model line-up includes still slimmer versions of the 225 centre speaker and Radius One soundbar, together with a new Radius 200 centre-channel for shelf or rack mounting, and two enormously powerful yet super-compact active subwoofers: Radius 380 and 390.

And the re-energised line-up has already shown its quality by collecting five glorious stars from What Hi-Fi? Sound & Vision magazine. In its October 13 issue, the UK’s most dynamic forum for high value AV performance is suitably awed by the new Radius R90 HT1 package, starring the refreshed 90s, new 200 centre and bass-bulging R390 sub. It says “if you yearn for a discrete 5.1 set-up, this should be on your radar, because it’s a remarkable success…integration between fronts, rears and the sub is seamless. The surround field is gapless, effects flow between channels effortlessly and you’re immersed in the action…it (the 390) displays a potent combination of precision and weight with no fear of bottoming out or losing its grip”.

Living with great audio has never been easier.


Load more

User reviews

Add a review

You might also like

Radius 270

Suggested accompaniment

Radius 270

  • New 4” C-CAM® bass driver - Radius features all new bass drivers with concave cone profiles, introduced by our top-of-the-range Platinum speakers and applied subsequently to Gold GX.  Extensive research and FEA modelling have allowed us to perfect the relationship between the new radiating diaphragm and its motor design, introducing larger motor sizes and voice coils for increased excursion, higher power capability and reduced distortion.
  • New C-CAM gold dome tweeter - optimised to deliver the finest and widest performance within the compact Radius cabinets. It benefits from a more efficient rear-venting design, releasing air trapped and compressed at the back of the tweeter dome, and guiding it around the drive assembly to a rear-loading chamber.
  • HiVe®II port design - Straight from Platinum’s design blueprint, the HiVe reflex port makes its Radius debut. It’s shaped to have the same effect on airflow as a gun-barrel on a bullet. Rifled grooves inside the port help to accelerate the flow and reduce turbulence, so air moves in and out of the port more efficiently, for a faster more dynamic bass response.
  • Single through-bolt driver fixing provides mechanical de-coupling and enhanced mid-band clarity and resolution. The through-bolts also act as rigid cross bracing to give a very solid non-resonant cabinet.
  • Front and rear ported reflex design


De-Tox CD

Custom-developed for Monitor Audio and utilising advanced simulation technology, the new De-Tox CD will help you to run-in your speakers in less time and more comprehensively than is possible with music or other burn-in signals.