Let’s get the basics out of the way first: the iSine 20s cost $549 with a regular detachable cable or $599 with an additional Cipher cable that provides a Lightning connection for iOS devices and a built-in 24-bit DAC and amplifier. My review is based on the experience of listening to them without the extra Lightning jazz, because that’s the fairest way to judge the performance of the headphones themselves. The process of getting set up with the iSines is... well, it’s a process. You have to discard all your usual expectations of easily portable in-ear headphones, because that’s not what these are. The vast protrusions emerging from the iSines house a 30mm (1.2-inch) planar magnetic diaphragm, which is basically an ultra-thin sheet that dances back and forth, generating sound waves that are then funneled into your ear. There’s no getting around the bulk of such a large sound driver, and Audeze hasn’t really figured out a design that makes the iSines easy to strap to the sides of your face. In the box, you get three sets of almost identically sized silicone tips, one shirt clip, a cleaning tool, and a 128MB USB drive with the iSine user guide. Two sets of over-ear hooks are provided, but I find myself most comfortable with the alternative plastic inserts that fit inside the ear cavity to stabilize each headphone. The over-ear stuff eventually makes my ears hurt, whereas using the headphones without anything holding them in place is an unstable proposition that leads to them falling out of my ears. With the plastic stabilizers, the iSine 20s rest lightly and easily inside the ear, and they can be worn for hours at a time, provided you don’t need to move around too much. To minimize unwanted resonance resulting from reflections within the housing, the exterior of the iSines is semi-open — meaning they don’t insulate you from exterior noise very well and they leak some of their own sound out. Audeze provides a nice and rugged nylon case for these, but it’s quite bulky and doesn’t provide the same sort of impact or water ingress protection that a hard shell case would have done. Without the Cipher cable, you also don’t get an in-line mic. Basically, every