The Audeze Sine is a special headphone. At $450 it's one of the least expensive headphones that use planar magnetic drivers, which tend to sound very coherent and spacious, with low distortion. If "planar magnetic drivers" sounds Greek to you, you're in good company. Ultimately, what matters is that it's a totally different technology than what you find in nearly all other mainstream headphones. If you want the technical details, check out Inner Fidelity.
But what you should know it that what makes this headphone (and the Oppo PM-3) special is that -- in a world where most planar magnetic headphones have open-back designs -- the Sine has a closed-back design. In fact, it's one of the few planar magnetic models that's optimized for mobile use -- it's being marketed as the world's first "on-ear"planar magnetic headphone.
Open-back models generally offer more open, airy sound, but they also leak sound, which makes them less than ideal for use in the presence of other people.
While it doesn't it sound as rich or open as Audeze's higher end open-back over-the-ear models -- some of which cost in the thousands and are audiophile favorites -- it's one of those headphones that sounds so good you want to go back and listen to your music collection to hear the little details that lesser headphones don't reveal. It's just a great-sounding headphone.
It's worth mentioning that although Audeze calls this an "on-ear" headphone the earcups fit around my ears -- barely anyway. But I don't have a big head, so the earcups will indeed sit on some people's ears.
The Sine is very attractively designed, with a leather covered headband and earcups and sturdy metal parts. It folds flat into an included storage pouch. The thick tangle-resistant flat headphone cord detaches and iPhone users can swap out the standard analog cable for Audeze's Apple-approved Cipher Lightning cable. That creates an all-digital connection and has a digital-to-analog converter (DAC) built into the headphone's remote and overrides the iPhone's internal DAC. It slightly boosts the sound -- and sound performance -- while drawing a little power from your iPhone.
That means if -- as many suspect -- the iPhone 7 that we expect to be announced in September drops the standard headphone jack, the Audeze Sine will be one of the first wired headphones to be compatible with it.
That Lightning cable is included in the $500 bundle of the headphones (along with the standard cable with a 3.5mm plug). Along with the inline remote, the Lightning cable has an integrated microphone for making calls with your iPhone. However, the standard cable with a 3.5mm plug does not have an integrated remote or microphone, which is too bad.
We compared the Sine to a couple of headphones: Oppo's $400 PM-3 closed back planar magnetic headphone, which we also like a lot, and Beyerdynamic's T51i, one of our favorite on-ear headphones. (Steve Guttenberg, who writes CNET's Audiophiliac column, and home audio editor Ty Pendlebury also listened to the headphones.)
Let's start with the Oppo, which is slightly less stylish than the Sine, has an over-ear design and is little more comfortable to wear over long periods. The Sine is comfortable but not supercomfortable and -- at 8.1 ounces or 230g -- it's got some heft to it. But the Oppo and Sine do a decent job passively sealing out ambient noise.
The Sine is a little bit more forward and revealing than the Oppo, which means it'll make well recorded tracks sound even better but bring out the harshness in badly recorded material and make it sound even worse. So it goes with really transparent headphones. And the clean and natural sounding Sine is just.
A a result, it works better with some types of music than others. For instance, it's not ideal for listening to rock tracks (and I don't mean rock ballads, which it's well suited for). It's great with jazz, classical, R&B, and bands like Beach House, a "dream pop" band. The Sine's open qualities bring out the ethereal qualities in tracks like "Myth" and "Elegy To The Void."
Compared to the Beyerdynamic T51i, the Sine is the more revealing, more transparent headphone, but the T51i is smaller, arguably more comfortable, and costs less at around $250 online. The T51i is more forgiving and would be better with rock tracks, but overall the Sine is the better, more open-sounding headphone.
As far as the Cipher Lightning cable goes, don't expect to get a high-quality headphone amp for the extra $50. Using the Lightning cable does act a little like a headphone amp, boosting the volume and the bass (it also draws a little bit of power from your phone). However, a true headphone amp -- a good one anyway -- would improve the sound more significantly. I preferred the sound slightly using the Lightning cable, but depending on your tastes, you may prefer using the standard 3.5mm audio plug.
For instance, while the bass sounded bigger with Beach House's "Myth" using the Lightning cable, we felt a touch airiness was lost. And obviously, if you don't plan on using this with an Apple iOS device there's no reason to get the optional Lightning cable. (We also tested the Sine with a few portable high-resolution audio players.)
It's great to see Audeze bring planar magnetic to a smaller, more mobile oriented headphone. We liked this headphone a lot and would recommend it to anyone looking for a truly high-end sounding headphone that isn't incredibly expensive.