Panasonic RP-HJE900

Review is here: http://www.head-fi.org/forum/thread/502289/panasonic-rp-hje900-zirconia-review

These headphones are very unique, both in construction and sound. They are built of Cubic Zirconium, making them extremely durable, and have detachable cables. A jogger literally ran over mine, on concrete, and they aren't even scratched. The finish changes color from a gunmetal grayish color, to a bluegreenish hue in bright light. The cables, though having a slight memory character, are very thick and sturdy feeling, although they can add a bit of uncomfortable weight to already hefty earphones. Nevertheless, I've never had an issue wearing these cord up or down so long as I have a proper fit. They are shallow insertion, and comfortable enough to sleep with. Most earbuds/IEMs tend to die through cable failure, since they are constantly being put into stress because of their portablility, so it is a huge relief to see these have detachable cables which are compatible with Sleek Audio cables. One of my dogs chewed through the original cables(which miraculously still work most of the time, but sometimes the sound cuts out), so I was glad I was able to pay 15 dollars for new cables instead of 100+ for new earphones. However, they do suffer from one issue where the thin nozzle filters seem to fall off when doing a lot of tip changing, which pretty much 90% of head-fi IEM users do. This is not a big deal though, as many prefer having them off, and the issue is easily managable by taking a tiny piece of thin foam from some cheap earbuds and placing them into the nozzle(which also lets you comfortably modify the treble to your own liking)

Soundwise, the first thing to note is that these aren't for everyone. They are by no means neutral; but this doesn't mean they don't sound natural. Whether they do or not will depend on your ears and preferences. I am, fortunately, one of the many to whom these seem to sound very "natural", what with it's U-shaped sound signature presenting clear highs and (very) punchy lows. These extend powerfully all the way down to 20hz, while presenting a surprising amount of detail in the treble. Detail which rivals that of many balanced armature IEMs, by several accounts.  Though they have a pleasant decay at the bottom for realistic bass, they maintain necessary speed throughout the sound signature to provide ample detail in all the frequencies. Textured bass, clean mids, and detailed highs.

Though their soundstage isn't the widest, they seem to give the illusion of a large soundstage because of how transparent the sound is, and how realistic the timbre is. Separation and imaging/position is truly great, especially for a dynamic. One would think the Cubic Zirconium is just marketing, but not only does it provide these with outstanding durability, but also really reduces resonance to less than any HP I've heard. It's as if my brain feels that the sound emerging from these is so realistic, it artificially expands the soundstage so that it feels larger than any of my full size headphones. It is an intimate presentation that is able to expand accordingly to the music's demands. As a fellow head-fi member once described, their sound is seemingly "holographic".

I must emphasize again, however, that they simply aren't for everyone, but such is the case with pretty much every headphone. What make these headphones great for some may be what makes them lackluster for others, and viceversa. For those who need something with pristine detail to bring out the nuances in classical music, but still want the bass to get you moving through your Hip-Hop tracks, these are a great candidate. I bought them when they were available for 109 dollars earlier in the year. At 120, they are still an amazing value.

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I really like these IEMs.  The casing is almost indestructible, they have detachable cables, and the sound is great and very clear for dynamic drivers.

The casing is made from Zirconium.  They're advertised as being related to diamond, which isn't true and a little too much marketing speak, they are indeed very very hard.  

The sound is a little bit V-shaped with too much emphasis on the bass & treble.  It can be fixed through the use of an equalizer, but it'd be nice if it were more neutral out of the box.  But the clarity is fantastic, the bass extension great, the treble very lively. 

The cable is very high quality.  My only qualm is that it is a bit on the short side.  If I use these with my iPhone in my pocket the cable barely reaches and will tug  if I turn my head while wearing them over the ears.  It really could be about 6" longer, but you can fix this easily through the use of something like the iLuv EA15, an iPod/iPhone remote that adds 7".  Or you can just replace the cables with Sleek Audio SA6 replacement cable, the port is the same.

Durability anecdote:  My Corgi likes to eat my IEMs and he got a hold of these once.  The earbud came unattached from the cable, he chewed on and he swallowed it.  I made him throw up with some hydrogen peroxide per my Vet's advice.  5 minutes later out the missing earbud came, covered in foam but absolutely scratch free.  I cleaned it up in some rubbing alcohol, let it dry out and put a new tip on it.  Much to my surprise it worked fine!  The screen mesh on the nozzle kept all moisture out and the driver was undamaged.  Can't say that about any other IEM - surviving 30 minutes inside a dog's stomach.