My first exposure to Monitor Audio’s Radius-series speakers came through a stereo system based on a small subwoofer and an adorable pair of tiny cube-shaped Radius R45 satellites—satellites so small they could fit in the palm of your hand. “Cute,” I thought, “and obviously well made, but they’re probably too small to use in a full-sized surroundsound system.” But these days the Radius family has grown to incorporate much larger and more capable models including six satellite/center-channel speakers and two powered subwoofers, plus necessary stands and accessories. The new models reflect the design aesthetics of the original R45s, but in a more sophisticated form (picture speakers that combine compact, flat-panel dimensions with an almost Scandinavian sleekness, tempered with gently rounded enclosure edges that add a touch of warmth and whimsy). What is more, the new, larger Radius models are suitable for use in surround systems that can fill a goodsized family room with sound.
There are more Radius system configurations than I can count, but to give you a sense of the scope of the lineup, I chose a review system based on a pair of flagship Radius R270 floorstanders as left/right main speakers, an R250 center channel, a pair of R90 satellites with optional floors stands as left/right surrounds, and the R720 powered subwoofer. Radius models are available in a delicious variety of finishes (rose-mahogany, walnut, silver, piano-black or piano-white.) Our pianoblack review samples proved so attractive that, after seeing them for the first time, TPV/AVguide Art Director Rob Amoroso (who knows an elegant design when he sees one) said, “I want them.”
Like all Monitor Audio speakers, the Radius series emphasizes advanced drive-unit technology, with most models featuring the firm’s signature CCAM alloy gold dome tweeters and MMP2 (metal matrix polymer) midbass drivers. The Radius system also excels in attention to small, critical details: Drive units are cinched tight into their cabinets by fasteners that apply tension from the rear, making the enclosures stiffer and less prone to resonance. Floorstanding models such as the R270 place binding posts out in the open and down at floor level, greatly simplifying cabling (bless you, Monitor, for not putting binding posts high above the floor or beneath the speakers). Wall-mountable Radius models ship with appropriate brackets, hardware, and mounting templates. Finally, as a welcome nod toward aesthetic flexibility, Radius speakers come with two sets of mesh grilles in contrasting colors. Monitor Audio attends to details others sometimes overlook.
But how does the Radius system sound? Most listeners notice three sonic characteristics of this system: first, its upper midrange/treble transparency; second, the openness and beguiling clarity of its midrange; third, the warmth and smoothness of its bass.
The Radius system’s upper midrange and treble transparency have everything to do with the “house sound” of Monitor’s C-CAM gold dome tweeters. Their strengths include excellent high-frequency extension, good resolution, and excellent perceived transient speed, so that when you listen for fine high-frequency details (the different voices of various cymbals within a drum kit or the upper harmonics of voices or strings), you may find the Radius system effortlessly retrieves information comparable systems tend to miss. However, some listeners find Monitor’s tweeters overly bright and therefore splashy or aggressive on hard high-frequency transients. The incisiveness of the Radius system’s highs is a double-edged sword, sometimes cutting through soundtrack clutter and improving dialog intelligibility, but at other times imposing a hint of unwelcome upper midrange/treble edginess. Because knowledgeable listeners sometimes differ in their reactions to the Radius tweeters, I encourage prospective buyers to evaluate their sound for themselves.
One of the most pleasing aspects of the Radius system is the unforced clarity and openness of its midrange. This pays real dividends on male and female voices and helps highlight small textural details that bring film soundtracks alive. A good example occurs in The Matrix, during the scene where Neo is taken to meet the Oracle. Though I have watched this film many times, I never noticed until hearing the soundtrack through the Radius system that there is music playing softly—almost subliminally— in the background as Neo and the Oracle converse. The Radius system makes such details easy to hear, without beating the listener over the head with them. In addition, the midrange drivers, which are small in diameter and therefore disperse better than larger drivers, serve up imaging arguably superior to that from larger, more costly Monitor models. The trick, here, is that these drivers are light, stiff, and fast—in a word, agile—and therefore able to keep up with the blazing speed of the Radius tweeters. To appreciate what a difference this can make, try a track from one of the superb Chesky multichannel SACD recordings— a favorite of mine is “Not While I’m Around” from Christy Baron’s Retrospective—to savor the threedimensionality of the sound. At its best, the Radius system treats you to a coherent 3D soundscape, not to the sound of five channels blaring forth from the corners of your room. The only catch is that when tweeter-induced moments of midrange/treble edginess arise, they tug your ears back towards the speaker enclosures, breaking the 3D illusion. Fortunately, these intrusions don’t happen very often.