Headphones

We've reached the stage in the renaissance of the planar magnetic (aka isodynamic) headphone where merely being one is no longer worth more than a passing mention. In fact it's a few months since I've had anything but PM headphones arrive for review. So to be more than the PM headphone du jour, any new model needs something extra: a true USP.

And the £1900, top-of-the-range Mr Speakers Ether 2 has just that. A USP that anyone will welcome who likes the distinct way that this type of headphone sounds, but not the fact that PMs typically weigh half a kilo or thereabouts. Because the Ether 2 headset weighs just 290g (specified – we measured 291g but who's quibbling about a solitary gram?) and is immediately more comfortable and less burdensome as a result.

Comfort Zone
Not that MrSpeakers shows much intention of this being a headphone you'd schlep about with you. Yes, it is supplied with a chunky zip-up hard-shell case but it's so large you'd need a poacher's pocket to carry it in. And while less than generous in length for use at home, the 1.9m connecting cable – we chose the unbalanced version, though there is a balanced option – is too long to be practicable on the hoof and in any case is resolutely intended for use with ¼in jack sockets. No adapter cable is provided for mini-jack connection, and the Neutrik jack plug at the source end is not a sleeve adapter with a mini-jack nestling within.

At the headset end the cable splits to connect separately to each capsule via locking Hirose connectors, which may be no more effective in practice than the mini-jacks widely used elsewhere but certainly look the part on a headphone dangling this order of price tag.

Lightness alone, of course, is necessary but not sufficient to make a headphone comfortable to wear. It must also have earpads that don't squash the ear, and should apply only moderate head clamping force at worst. The Ether 2 doesn't disappoint here. The wedge-section earpads – thicker at the rear than at the front to angle the capsule to the head – have an ear-shaped rather than circular cut-out which is capacious enough to accommodate all but the largest pinna without bending it or pinning the earlobe. And the head clamping force – which I measured at 4.7N for 150mm head width – is below average, even for open-back headphones.

Still, there are issues here. First, if the cable rubs against clothing it generates disconcerting levels of mechanical noise from the capsules. If MrSpeakers were to supply a clip for attaching the cable to clothing it would help, but ideally a more complete solution (starting with a smooth-finish cable covering) is needed.

Second, if you play pink noise through one capsule only you can just hear some carry-over of sound to the other due to headband vibration. This is at a low level – certainly much lower than you'd expect from tapping the headset while wearing it, or from the thin circular-section loops that form the headband – but ought to be further suppressed.Third, and most seriously, the Ether 2 is unusually sensitive to the integrity of the earpad seal, particularly for an open-back design. Many open-backs evince little loss in LF output if the earpad seal is compromised, but not the Ether 2, which sheds bass output as readily as most closed-back designs if the earpad seal is less than perfect. What this means, in effect, is that if you wear spectacles and/or have copious hair, you are unlikely to enjoy the impressive bass extension this headphone is capable of when its earpads seal tightly to the head.

Novel Tech
One major reason for the Ether 2 being light for a planar magnetic design is that its 71x45mm drive units are single-sided – in other words, magnets are arrayed along one face of the diaphragm rather than both. While this might be expected to increase distortion, there was no sign of that during our testing. And the drivers are interesting in two other respects as well. First, they use flared holes in the stator between the bar magnets – analogous to the flared ends of many modern loudspeakers' reflex ports – to encourage more uniform, laminar airflow past the magnet array as the diaphragm moves back and forth. MrSpeakers calls this TrueFlow.

Second, the diaphragm is pleated rather than flat, in which respect it resembles the foil of many (true) ribbon drivers, a feature which MrSpeakers calls V-Planar. Pleating the diaphragm in this way significantly reduces its tensile stiffness, allowing it, it's claimed, to displace more air at low frequencies while simultaneously improving dynamics and treble frequency response, and generally lowering distortion. It is also certain to affect the resonance behaviour of the diaphragm. (It's sometimes supposed that PM diaphragms don't resonate because they are, notionally, driven across their whole surface – but this is delusional. They do!)

All told, then, the Ether 2 is a technically and practically novel PM headphone, distinct from the herd.

Talk Show
Before these arrived [writes CB] I had been listening to a new recording of Vaughan Williams's Sinfonia Antartica [Onyx ONYX 4190]. The five superscriptions are spoken by the actor Timothy West – whose voice everyone recognises. Unsurprisingly with the Ether 2s straight out of the box it could have been any old narrator, while the orchestral music tended to be thin, recessed and flat. But after a 20 hour burn-in, things improved...