Crack open your current on-ear headphones (actually don’t, just take our word for it) and you’ll find a dome-shaped dynamic driver. Crack open Oppo’s new PM-1 headphones (again, don’t, they’re very expensive) and you’ll find something quite different: a flat disc.
This is known as a planar magnetic driver (hence the PM in the name), and Oppo claims it offers less impedance and less distortion, which allows for a very faithful, ‘high-resolution’ response. Oppo showed us many, many graphs to demonstrate this. But what are these babies like on the ear?
Oppo isn’t the first company to make flat-driver headphones. In the early 90s, some engineers from Sennheiser were asked to design the best possible, money-no-object cans possible. The result was the Orpheus system, a set of headphones with flat, electrostatic drivers and their own special amp (which could only be unlocked with a special key, because those are Daddy’s headphones). Since then, electrostatic ‘earspeakers’ and their accompanying amps have sat at the top of every chin-stroking audiophile’s wishlist, but they’ve remained a niche product - delicate, heavy, useless without a power source, and furiously expensive, they’re for indoors listening.
Oppo intends to change that, with headphones that use a flat driver but are light, stable and durable enough for day-to-day use. They plug into phones and tablets, too, without the headphone amp required by other electrostatic headphones. At £1099, though, they are still expensive enough to make you wish you’d tried harder at school.
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When you're trying to explain to your family why they won't be eating for a month, you can point out that your new headphones are built to last. Each headband is stretched 20,000 times and then fully extended and closed 20,000 times, and then the earcups are rotated, you guessed it, 20,000 times. The headband and cushions are made from lambskin, although you can use velour ones if you’re a vegetarian or just prefer a softer thing pressed against your face.
And actually, you don't actually have to spend all that much: the £699 PM-2s (available June) use different materials - some of the metal is replaced with plastic, the lambskin is swapped for synthetic pleather, and you don’t get a fancy wooden box - but the disappointment of not having lambskin on your face will be tempered by the fact that they use the same drivers, so they will sound the same.
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Let’s be clear, though: these are not headphones you should wear on the bus. Even if your fellow busketeers don’t realise that you’re wearing a grand’s worth of hi-fi on your head and decide they’d like to own them instead, you won’t make any friends wearing the PM-1s because, like all flat-driver headphones, they’re leaky. Very leaky. This is deliberate - they’re open-backed, many high-end headphones. But despite their more normal construction and their compatibility with phones and tablets, these aren’t walking-around headphones. These are for sitting in your Special Chair, sniffing carefully at a bulb of vintage Cognac that you’ve purposefully chosen to match the smell of your rare vinyl.
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So how do they sound?
In the busy room where we first tried them, the fact that they allow a fair bit of external sound in got in the way of proper judgement, but it was immediately obvious that the PM-1s offer a majestic listening experience. They’re a little heavier than your average cans, but they’re as comfortable as sloth in a bag of warm feathers. For most headphones and speakers there’s little point (in this writer's opinion) in playing higher bitrate MP3s or 24-bit FLACs, but the PM-1s are a different kettle of bits, because they have the flat golden tongues to enunciate all that extra information.
And are they worth the money? Well, they're very expensive, you can't wear them on the train, and they let in noise. But these aren't for everyone. They're for the audiophile who wants to spend evening after evening swimming in a warm, dark womb of high-resolution sound. And if you want to do that, £1100 (or £700) isn't that crazy: large hi-fi systems can easily run to five figures. Stay tuned for our full review.
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