Cambridge Audio Minx S215 Speaker System
The cube speaker at the heart of Cambridge Audio’s Minx satellite/subwoofer set has become an enduring form factor for people who don’t like loudspeakers. Of course, in their zeal to get speakers off the floor, some speaker-haters poke holes in their walls for in-walls. But not everyone is willing to go to that extreme. And while in-wall and on-wall speakers have no footprint, they do have what you might call a wallprint. For folks who don’t like speakers, don’t like holes in their walls, and don’t like wallprints, but do like movies and music, the cube speaker—something the size of a Girl Scout’s fist—shapes up as the least invasive solution.
Cube speakers have been marketed as both standalone products and integral parts of compact systems, including lifestyle systems, both surround and stereo. But they have a special aesthetic aptitude for surround because they’re too shy to dominate the style of a room. Speakers are like framed pictures: The bigger they are, the smaller the room looks. The smaller they are, the bigger the room looks.
Sitting on slender stands, cubes look cute, maybe even cute enough to make a speaker-hater stop hating. You can push them up against the wall often without worrying much about room-boundary-induced bass bloat. Cubes don’t have much bass to begin with, and the little subwoofers they come with can often use some extra boundary reinforcement. Cubes are also a natural for wall mounting. They’re so lightweight, you may not even need to find a stud behind the drywall. Buy some cubes in white, mount them on a white wall, and you’ll hardly notice them.
Inside the Cube
Back to the Minx, Cambridge Audio’s new satellite/subwoofer line. There are two Minxes, the single-cube Min10 used in the system reviewed here and the dual-cube Min20—the two-fisted version, if you will. The cube measures hardly more than 3 inches in any dimension. Reviewed here is the S215 satellite/subwoofer system, with five cubes and a 6.5inch, 200-watt sub ($800). The S315 system ($1,000) has five cubes with an 8-inch, 300-watt sub. The S325 ($1,400) has five dual-cubes and an 8-inch, 300watt sub. The S525 ($1,800) has five dual-cubes and a 10-inch, 500-watt sub. The 2.1-channel systems are the single-cube S212 ($550) with a 6.5-inch, 200-watt sub and the dual-cube S322 ($900) with an 8-inch, 300-watt sub.
The Minx line was two years in the making and comes surrounded in engineering rhetoric, most of which can be boiled down to the following fact: The 2.25-inch drivers inside the little cubes do not utilize cones or domes, as in conventional satellites. Instead, they have specialized flat diaphragms using technology licensed from HiWave, formerly known as NXT. This lets these cubes spread sound around the room more evenly.
If you’d like to know more, the diaphragms in these drivers are intended to operate as pistons at low frequencies as expected. But they’re structured to operate as bending wave panels at higher frequencies.
Cambridge calls these flat drivers Balanced Mode Radiators (BMR) because bending modes are controlled by multiple masses distributed around the diaphragm, which balance the mass of the voice coil. This better controls and balances the diaphragm’s movement and bending. For lightness, the voice coil is made of copper-clad aluminum as opposed to pure copper. For smallness, it has a neodymium magnet. The BMR diaphragm is made of paper, a material chosen not for economy, but because its strength-to-weight ratio is “four times that of aluminum, three times more than glass fibre, and double compared to Kevlar.”It’s not just a Post-It note stretched across a cube. It’s a composite honeycomb sandwich with paper skins surrounding a paper core whose depth and thickness are engineered expressly to start bending at the frequencies where most speaker drivers would start beaming. In speaker parlance, beamy is not a compliment. It means that output falls, especially at high frequencies, and tonal balance shifts as you move out of the sweet spot. The Minx avoids this. On my sofa, every spot was sweet.