Pros: Bass extends very low and has great clarity, sounstage is wide, comfy phones, quality build, packaging and accessories are excellent.
Cons: Mids are slightly recessed, not very portable but has cable for it, it LOOKS like beats, somewhat heavy, full MSRP
The Denon AH-D600:
First thing you notice when getting the headphone is it's fantastic packaging. From the outer sleeve sleeve to the actual fold box, everything speaks quality from a reputable company. In a world of packaging having as much importance as the actual product, Denon does not disappoint. Opening the package displays the beautifully crafted headphone on a silk bed, something you'd expect Sony to do and something of a throwback to the yesteryears. The cables, adapter, travel bag, and documentation are underneath the bedding and are also as pleasantly packed.
The actual headphones themselves scream quality made. The cups, the leather headband cushion along with the super premium ear pads with white stitching. The feel of the headband might seem similar to one juggernaut headphone company that sells mostly hype and a bass-heavy sound but everything else is a clear step up, by a mile. Putting the headphones on, you feel your ears wrapped by the pads and the comfort of the leather against your skin. You also notice that it isolates the outside world very well and this would be something you can wear in loud surroundings like public transportation, albeit a bit showy for the more reserved but isolation wise it's fantastic. And for those that don't mind showy, you'll separate yourself from the rest with the words clearly marked DENON.
Taking out the cable from the packaging, you notice the custom looking thicker cable made for home use is something most head-fi members will paying upwards of $150-$200 for, if not more. No need spending as much as the headphone to have a nice cable here and really something all headphone companies should catch on. The thinner mobile use cable has the Apple product controls built-in and is shorter in length, perfect for the traveling audiophile!
Now the important stuff, sound:
The Denon AH-D600 has a V shaped sound, making it a fun headphone. The bass is absolutely tremendous and well executed. It has great impact, presence, and extends LOW. 20hz on the new Chesky sound bites? No problem and well presented! On the heartbeat bass test the D600 outperforms the HE4 out of the Project Ember and that's saying something. I would say bass quality is of the HE400 if not better (although this comparison is from extended memory).
With the prominent bass, the mids are are untouched albeit being recessed in the V signature. Not to the point where you are missing parts of your music but enough to notice it is a step back in the stage around other instruments. This might not be the go-to headphone for music that is meant to have pronounced vocals but for movies where vocals are very important it works fine and well audible. If a V signature puts you off, read the brief source pairing below that might change your mind. The highs are well extended without sibilance, airy but presented a bit on the thin side. It has great detail and clarity.
Something that strikes me on this headphone is it's great amount of clarity. Coming from a good source of music and chain it really presents above the level of mainstream headphones while having that mainstream sound signature. About the recessed mids, when I plugged this directly into the NFB12 the highs seem more level with the mids and now you have basically a warm phone with excellent bass extension. The highs still extended well but doesn't have that thin sound when coming from a neutral or bright source. It could be the way Denon has tuned this headphone, which is for for Apple devices and their warm signature.
Conclusion. If you like a mainstream headphone, something that has excellent build and sound of an audiophile company but has the popularity and fashion to back it, these are the go to. They're great for anything that calls for good bass. I wouldn't call them bass-head levels as they do the bass gracefully even if it's prominent but for those looking for a flat or something with a more reference bass probably should keep looking elsewhere.