Verdict
The iSine 10 sound very impressive for the money. Just remember they’re open-backed headphones in a different form factor and you’ll be fine.
Pros
- Great mid-range resolution
- Spacious out-of-head sound
- Lightweight and comfortable
- Unique looks
Cons
- Only really suitable for home listening
- Treble can be harsh
Key Features
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Review Price: £349.00
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Open-backed in-ear design
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30mm planar magnetic drivers and Fluxor magnets
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Optional Lightning cable with inline DAC
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3 eartip sizes
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Replaceable 3.5mm cable
What are the Audeze iSine 10?
The iSine 10 are a real oddity – and not just because their styling brings to mind TIE Fighters or that window in Return of the Jedi. These are the first earphones to squeeze non-hybrid planar magnetic drivers into what’s still (just about) an in-ear design.
In addition to a standard 3.5mm cable, the iSine 10 can be bought with a Lightning cable as well (for £399/$399), meaning iPhone owners don’t miss out. In fact, the Lightning cable’s inline 24-bit DAC (digital-to-analogue converter) actually gives the iPhone an audio boost.
However, these earphones feature a compromise that rather limits their appeal…
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Audeze iSine 10 – Design
Yeah, so… These are weird, eh? But they’re a good weird. Geek chic, if you will.
The 30mm planar magnetic driver in each earbud means the bulky outer part of the iSine 10 is pretty big and sits just outside your ear. A stem with a rubber tip just protrudes inside your lughole like you’d expect from any standard noise-isolating ‘phones.
You get three sizes of tip in the box, which is probably all you need, since these don’t rely on achieving such a precise fit as proper noise-isolating earphones do.

Two pairs of plastic earhooks are supplied – although the only difference between them seems to be that one is clear plastic and the other black. These just clip around the base of the stem and can be rotated to get the right fit. There are also two different sizes of rubber in-ear stabilisers supplied as an alternative to the hooks. These fit the same way but nestle into the upper part of your outer ear.
However, the iSine 10 are almost light enough (20g per side) that you could happily choose not to bother with either. I used the plastic hooks just because I get paranoid about in-ears creeping out.
Another side effect of the huge drivers is that they need room to ‘breathe’, and so the iSine 10 are open-backed – they have an open grille behind the drivers. That grille has been turned into a real design feature, though, with a healthy dollop of sci-fi panache. It really does remind me of a TIE Fighter.
The open-backed design, of course, means these aren’t noise-isolating. They leak like a leaky thing. As such, they’re really only suitable for the same sort of listening situations in which you’d use open-backed over-ear headphones – so mostly just in the comfort of your own home, with no one nearby to be annoyed by the tinny music whispering out.
There’s also nothing at all premium about the feel of the iSine 10 – they just seem very light and very plastic. But that’s completely intentional, in order to keep that weight down and ensure they’re as comfortable as possible for long listening sessions.
The optional Lightning cable with built-in DAC costs an extra £50/$50
Two cable options are available, with a 3.5mm ‘ribbon’ version as standard, plus a more sophisticated Lightning cable with an inline 24-bit DAC for use with iPhones and iPads if you pay the additional £50/$50. When using the latter, there’s also an iOS app that enables you to tweak the EQ during listening.
Audeze iSine 10 – Sound Quality
I did the majority of my listening with an Astell & Kern AK70 feeding files through either a Chord Mojo or Chord Hugo DAC headphone amp. Most of my digital music library is still made up from CD-quality FLACs and 320kbps MP3s, although I threw the odd Hi-Res Audio track at the iSine 10 too.

The first thing you notice about the sound of the iSine 10 is that wonderful spatiality you get from true hi-fi headphones. The open backs and large drivers combine to send the soundstage out beyond your ears and fizzing and shimmering around your head.
The only other in-ears I’ve heard that offer this sort of experience are the outrageously expensive Noble Audio Katana, which cost around five times the price of the iSine 10.
Starting with the delicate acoustic touch of Joe Purdy on his ‘Canyon Joe’ album, the iSine 10’s upper mid-range and extended treble gave a tremendous sense of realism to that gentle guitar and haunting harmonica. It had mostly the same effect on his drawling vocals, although the treble proved a little harsh and fatiguing at times.
Possibly because of the single small-ish driver, the iSine 10 tended to get particularly hard-edged around vocals when there was a lot going on. With something like ‘Slapped Actress’ from The Hold Steady’s ‘Stay Positive’ album, Craig Finn sounded more strained than he should.
However, resolution and transient-handling through the mid-range is outstanding, and the bass is reasonably tight if not particularly deep. That rumbling bassline at the back of Gorillaz’ ‘Clint Eastwood’ doesn’t make your gut tremble like it does with the very best headphones, but you certainly know it’s there.
The longer I listened to the iSine 10, the more I appreciated one particular aspect of them, though: comfort. Where I might wear over-ear headphones at home for an hour or two before needing a break and fanning my sweaty ears, I could wear the iSine 10 all day without a problem. That’s a surprisingly big deal, and definitely helps make up for some of their sonic deficiencies.

Should I buy the Audeze iSine 10?
The iSine 10 are a marvellous feat of engineering on one hand – cramming true planar magnetic drivers into (kind of) in-ear monitors is a real achievement. On the other hand, the need for those drivers to be able to breathe through open backs really limits their appeal.
Don’t come to the iSine 10 thinking they’ll be your commuter or office earphones. Not only do they leak sound that’ll annoy people around you, but they let so much external noise in that you’ll barely hear the music if you’re riding a busy train.
However, if you do most of your listening in the privacy of your home, and are sick of extended listening sessions with over-ear headphones getting you all hot and sweaty, these are the solution. There’s nothing else quite like them – apart from the more upmarket iSine 20 and the top-end Audeze LCD-i4, that is.
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