Introduction
The Koss ESP/95X is a (now discontinued) collaboration between Drop and Koss to produce a cheaper, nonportable version of the latter's electrostatic ESP-950.
The ESP-950 is a long-enduring headphone system with a stock energizer, having existed for decades and remaining unchanged in price and design to my knowledge. I've long considered venturing into electrostats through those cans, but for $1000 (sometimes $600) and the need to purchase an adapter before getting into that esoteric world I never pulled the trigger. Once Drop released them in 2020 or so, however, I paid the $450 and was both pleasantly surprised and disappointed. On one hand, for $450 I was getting a unique sound and old school estat plastic build I find very charming. On the other, the left driver has squealed and caused significant channel imbalance not long after buying them. Koss repaired them for nothing more than the cost to ship them and they haven't had trouble since, but getting anything done in the summer of 2020 was not easy.
I listened to the ESP-95/X through the stock energizer from June of 2020 until March 2022, at which point I bought a modded Sr-006tA from Mjolnir Audio. The sound upgrade was substantial and I'll be using that experience as reference.
Build and Comfort
Very lightweight and comfortable, but the plastic creaks a lot and there are frustrating driver issues. I've dropped them from desk height without any damage or affect but I wouldn't want to repeat the experience. I understand Drop collabs usually mean a lower price tag and slight style changes, but this would have been a great opportunity to improve on an old design. Koss has a legendary warranty with these cans so I'll call it a wash.
Bass
Through the Mjolnir amp, the bass is really special. It doesn't thump like the LCD-3 and it's not as tight or well controlled as the HD-800S, but it strikes a balance of being warm and always very fast. The speed on these cans means bass notes are always distinct and their presence makes every note feel natural. Planar dynamics are more euphonic, but they don't seem as natural. Overall the lower registers are not the strongest suit, but certainly a contender. The ESP-95/X punches well above its weight.
Mids
Vocals are much more ethereal than they are intimate, but very pleasant and satisfying. Jazz can lose some of the euphonic character that makes it intimate and enjoyable, but is made up for by the texture and presence. The FR isn't quite a smile, but the mids don't have the same exciting or sparkling quality that bass and highs do. That said, the ESP/95X provides a unique and enjoyable experience.
Highs
Sparkly and never sibilant, no matter the song. "Combat" by Heaven Shall Burn and "Good Bait" by Coltrane are my litmus test for a headphone's ability to present bright music as bright but not unpleasant or sharp, and the ESP/95X passes the test. Watain, a Swedish black metal band, hasn't updated their rough recording style much but it doesn't become grating as it might on bright headphones such as the Q701. Unlike the Q701 or even the LCD-2 (as compared to the LCD-3, at least) which can be dry with such tracks, the highs are energetic and well done.
Soundstage and Presence
"Ethereal" doesn't really tell you much until you've experienced an electrostat. Imagine instead that instruments are presented as in open air rather than a stuffy room, and play naturally. The presentation of these cans is definitely their strong suit and makes every track a fun experience. They don't achieve the LCD-3 or HD800S ability to present every song uniquely. That is, the ESP/95X injects some of its slightly bright and energetic character, but for $450 ($1750 with the Mjolnir amp) you can't complain a lot.
Conclusion
The Koss ESP/95X has phenomenal bang for your buck, scales extremely well with better amplification and provides a solid entry into the electrostat world. The build quality could use work but as long as you keep them covered (I use a Stax stand and plastic cover) and take care of them you'll do fine. You'll want to upgrade from the stock energizer and will need to buy/make an adapter for Stax-compatible amps. I purchased one from Mjolnir Audio for $100 with my amp and haven't had any issues.

The Sennheiser HD800 is a legendary headphone, even 11 years after its release. It's long been considered the last word about imaging and detail and the quality of an amp can be judged by how well it handles the HD800. It certainly had issues: the treble at 6k is sinfully hot, it's exceptionally amp-picky and the presentation is clinical and brighter than neutral.

The HD800S was released around 2016 with a tweaked black aesthetic, more Vader than USS Enterprise. More importantly, it came with a Helmholtz resonator in the driver enclosure to tame that 6k (There's a DIY mod - the Super Dupont Resonator - which attempts to address the issue, but as Tyll points out it's made of foam and may deteriorate with sweat) and a balanced cable.

I bought my own used pair about three weeks ago, and I've spent quite a bit of time with them since then.

Build Quality and Presentation
They're exceptionally built and feel like a very precisely designed headphone. It's light and made ofplastic but doesn't feel cheap in the slightest. Movement of the D-shaped cups is very smooth and tight, and once you have them placed they don't move. The connectors are a little lower than the center of the drivers, which relieves stress on the cable when they're hanging and reduces the footprint a little. Headband adjustment is smooth and sure. Position marks and "Sennheiser HD800 S/N XXXXXX Made In Germany" are etched on the metal. An extremely minor gripe is the balanced cable: it's way longer than necessary unless you need to walk across the room without taking off your headphones. Further, the mesh covering just makes plugging it into a locked XLR port harder.

Comfort and Isolation
Comfort is a little tricky on the HD800S: they're much, much lighter than the LCD-3 and have little clamp force, but the velour pads are harder and the effective headband area is smaller. If placed slightly off, the headband creates hot spots and the pads are uncomfortable. Once properly placed, however, the HD800S is superior in comfort to the LCD-3. Maybe someday we'll get Denon D7000 comfort in a TOTL can, but not here.

Sound
The HD800S has an analytical, bright-side-of-neutral signature. As with the LCD-3, I've been using the Audio-GD D27 as my amp/source which has a very neutral and flat response. A warm tube amp might make them a little more euphonic, but I don't believe in equipment or EQ that 'fixes' a headphone. The HD800S may be a tweaked version of the HD800, but from others' impressions of the latter it's not fixed. It doesn't have the romantic, laid-back character of the LCD-3 but it has the unique ability to make every piece of music sound unique. As if the headphone sounds like the music, rather than the music sounds like the headphone.

Soundstage and Imaging
Wide, expansive, realistic soundstaging and highly precise imaging are the biggest draw of this headphone. No matter the quality of the recording or the genre, instruments are astonishing in how precisely they're placed. String music is somewhat lacking in body compared to the LCD-3, as if the cello is a clear white line rather than an off-white line with resonating dust. Percussion is really something special because it has such clear body and place in every track, so much so that focusing on drums can immediately clarify chaotic music. Jazz music is my favorite genre with the HD800S; the soundstage has just enough width and separation to transform the experience. Diana Krall's 'Night and Day' is perfect. The LCD-3 handles Coltrane and powerful heavy metal much better, but nobody can touch the HD800S for Diana Krall.

Bass
The HD800S doesn't have the sub-bass energy or body of the LCD-3, but it has tightness and quality in the mid-to-upper bass region in spades. Slam can provide a euphonic character and I prefer the Audeze bass presentation, but the HD800S flavor makes classical music and more intimate vocal music balanced across the spectrum. Bass-heavy music is still fun due to their speed and punchiness even though it lacks a little in quantity. Case in point: Morbid Angel's album Illud Divinum Insanus has a lot of groovy bass rhythms that can get lost in the a powerful bass presentation.

Mids
The mids are accurate and have excellent clarity but don't have the body or naturalness of the LCD-3. Planars have better mids than regular dynamics in my experience, but the clarity and imaging of the HD800S makes them a close second. Vocals are balanced and clear but could stand to be more intimate on vocal tracks. This doesn't detract from their quality, however; it's a matter of unity between technical performance and sonic character. Classical music, especially with heavy cello presence, opens up quite a lot in the mids region. Opeth has an airy, ethereal quality that I appreciate very much.

Treble
Hot treble is never pleasant and it's certainly more emphasized in this headphone than Audeze, but the HD800S doesn't necessarily artificially enhance high notes. Heaven Shall Burn's album Iconoclast Part III is sinfully bright. On the Grado SR-80 and AKG Q701 it's just shy of a mess and may even be grating on even slightly bright sources, but the HD800S stays on the side of honest. The LCD-3, by comparison, is somewhat shelved down in the treble region which may explain its romantic character. With the additional clarity and imaging of the HD800S, saxophone and higher guitar notes aren't competing against a bass-heavy signature. I dislike bright headphones but find these a great complement to the LCD-3.

Conclusion
The HD800S is airy, revealing, detailed, fast, and very nimble. It pairs well with a dead-neutral amp like the D27, is built fantastically and provides an excellent complement to warmer or more intimate headphones. I haven't heard the HD800, but its tweaked younger brother embodies much of what I hoped it would. Comfort is iffy and the presentation (especially the mids) lacks warmth and romance, but the soundstage, imaging, and clarity are absolutely top notch. I recommend them very highly for someone who enjoys jazz and classical music, and even moreso to someone who enjoyed the Q701.

I've been a Head-Fi'er for almost 10 years now, and during that time I've seen orthos explode in popularity and variety. When the LCD-3s were released, Hifiman, Audeze, and Fostex seemed to be the only manufacturers of planar magnetic headphones I heard about. Now we've doubled the offerings, both in what models manufacturers produce - look at how Audeze has expanded their line - and the price range and no. of manufacturers (Rosson audio, Monoprice, Empyrean, etc.). Nonetheless, my heart has always belonged to Audeze - the LCD-2's timbre is just that well-suited to my tastes. I've always wanted an LCD-3.
The LCD-3s had a troublesome start: the price was twice that of its brother; there were an unsettling number of driver failures; Head-Fi'ers were reporting cracking at the XLR connection and a noticeable veiled upper midrange. I'm pleased to see how much Audeze has improved since then: angled metal connectors, the Fazor mod, pre-treated wood, vastly improved balanced cable quality, to name a few.
I purchased an Audio-GD D-27.28 in August of 2019, which had been my first major upgrade since I bought the NFB-10SE in February of 2012. Not long after, I saw a pair of like-new Audeze LCD-3s for $1245. I haven't seen that steep of a discount before or since, so I 'had' (read: I had lots of disposable income at the time) to pull the trigger.
Presentation and Build Quality
The presentation of these headphones is beautiful: soft brown leather pads, luxurious wood, in a very sturdy travel case (I miss the black glossy wood cases, but engineers are a practical breed too). They're heavy in the hands, much like their predecessor, but the suspension headband mitigates that well. The LCD-3s exude craftsmanship, like an antique wooden chair. The leather on the pads is kind of flimsy for a headphone of this caliber - I'm getting wear after 7 months of gentle use. There are no nitpicks for a headphone that retails for $2K.
Caveat: the braided cable is lightweight and stylish, but Audeze could definitely learn something from Sennheiser in designing balanced cables. Every time you take the headphones off, the cable twists slightly and it doesn't take long for it to be a tangled mess. I wouldn't mind a stiffer, heavier cable if it means I'm not constantly unplugging my headphones to fix the tangle. I have to take off a half star for the cable and pads.
Comfort and Isolation
They are ~450 635 grams, which is quite heavy for most cans. The suspension headband mitigates the clamping force somewhat but they're not as comfortable as the HD800S (which I will be reviewing in time). That said, the leather pads are excellent and earn their praise. There's no isolation, but that's to be expected with completely open headphones.
Sound
I've been listening to these through an Audio-GD D-27.28 so I can't speak to how they'd sound on a lesser amp but I've heard they scale extremely well. The overall sonic character, even with a no-nonsense unit like the NFB-27, makes the LCD-2 sound dry and uptight by comparison. Everything feels so effortless and relaxed it makes the most complex and chaotic passages a joy to listen to. I was in shock the first time I listened with them to The End by Demon Hunter - a song I thought I was intimately familiar with. Cannibal Corpse feels like someone turned on a blast furnace in your skull (in the best way possible) while Coltrane is like a relaxing summer day.
Bass
Wow. The power, precision, and depth of the bass on these cans is phenomenal. It can handle slam, but it's also got speed and refinement. It is somewhat behind the HD800S in terms of precision, but it wins by a great margin in musicality. Hate Eternal feels like an elder god shaking the Earth, while Takuya Kuroda is liquid and refined. The bass is just right.
Mids
Vocals, male or female, are mind-blowing. Voices are natural, pristine, and musical. Diana Krall is an angel and the male vocals in Heilung are haunting and gripping. The LCD-2 seems dry and edgy by comparison, and I previously crowned them king of mids. The HD800S is analytical and precise in its vocal presentation, which has its own merits in very well-recorded music, but the LCD-3s are so much more euphonic. One minor caveat, however, is a troublesome loss of clarity at around 6k. Certain string notes and cymbals lack the definition and presentation that's clear in the HD800S.
Treble
The LCD-3 have much improved treble over the LCD-2. It's more relaxed,sparkly, and well-executed than the LCD-2 and certainly not as bright as the HD800S. Higher registers on classical music remain pleasant and listenable. The LCD-3 does everything with impressive ease and competency, even though the treble is the weakest.
Soundstage and Imaging
Like the LCD-2s, the LCD-3s are very intimate headphones. They work best with well-recorded jazz and metal because they lose some of the coherency and separation required for orchestra once the soundstage gets wide. They aren't terribly far behind the HD800S in the size of the soundstage and they're notcieably superior to the LCD-2 but the former might be a reflection of diminishing returns. Most importantly, they work extremely well for the music I typically enjoy. Instruments are well-defined, well-textured and present themselves in a realistic manner by and large and it's not a forceful or grating presentation. The sonic character of the LCD-3s is so pleasant that you can simply relax into any music and enjoy it. I wouldn't call the presentation laid-back or relaxed like the HD650, more that the headphones have achieved mastery and everything feels effortless.
Summary
The LCD-3s are a welcome upgrade to the LCD-2s in every single way. They aren't the last word in imaging and detail like the HD800S, but they have a liquid and euphonic presentation appropriate for every genre and mood. The pads still need work and the cable is frustrating, however, and the dip around 6K can make some string passages lose definition. Can we get Audeze on making detachable pads? I'd pay extra for the pleasure of not using those applicator rings when I inevitably replace the pads.

Introduction:
  I purchased the Q701s in September of 2012 after thoroughly enjoying an audition with a friend of mine's about a year earlier.  I had heard a lot about AKGs beforehand: polite, analytical, cold and detailed.  I wasn't prepared for how exciting and energetic they could be even through my relatively weak Nuforce Icon HDP.  After a little more than two years of owning them (and purchasing a pair of V-Moda M100s for mobile use), they had become my main headphone after the left driver of my beloved LCD-2s went kaput.  
Design and Comfort
 I thought the green Q701s were a little silly looking so I chose black.  They are elegant, high-tech looking cans with clean lines and excellent symmetry.  Not quite as high-tech as the HD800s, but they're definitely more space-age than my robust M100s or my luxurious LCD-2s.  The headphones are otherwise very light, both on the head and in the hands.  I've always thought suspension headbands were the way to go both for stylistic reasons and ergonomic considerations, but AKG did well in removing the bumps in future offerings.  As well, the cushions are still firm and slightly uncomfortable after years of frequent use.
Equipment: Audio-GD NFB-10SE, Foobar 2000, pain-in-the-rear 20ft cable
Highs
 Being a cold headphone, the highs can be very sibilant on some progressive and electronic albums.  Even on upper mids listening can become fatiguing for albums that aren't well recorded.  Bright recordings are headache inducing and electronic music can be painful.  That being said, orchestral music is always a pleasure.  Despite being polite relative to the M100s or LCD-2s, the highs can make the Q701s seem very aggressive.
Mids
 If you like mids, you will love the Q701s.  Vocals are intimate, textured and clear.  Female vocals are beautiful, smooth and engaging while male vocals have forced and engagement.  The Q701s are by no means at the level of my LCD-2s but I don't feel I'm losing a lot by switching from the latter.  Even tracks like 'Where the Hood At' have an excellent sense of engagement, and string music will make you shed a tear or two.  Mids are, by far, the best part of the spectrum with the AKG Q701s.
Bass
 This may sound eerily familiar from other reviews, but the Q701s have very weak bass.  It is, however, capable of producing insanely fast bass for death metal tracks ("Failure in the Flesh" by Through the Eyes of the Dead, "Ora Pro Nobis Lucifer" by Behemoth) and tight, punchy bass for jazz (Good Bait by Coltrane) and blues ("Played Twice"). 
Soundstaging, Transparency and Detail
 The Q701s are an excellent pair of headphones for all three.  Be it intimacy for violin and cello duos or vast halls for Gregorian chant, the Q701s handle soundstage well.  I prefer the consistent intimacy of the LCD-2s, but a wide-open soundstage definitely has its place for the music they do especially well.  
 Transparency is another excellent trait of these headphones.  While they sound artificial - my LCD-2s do spoil me - there is nothing between you and the music.  Every note feels very crisp and well-articulated.  Detail plays into this transparency as every note is well sculpted in space, almost to the point of making heavy metal hard edged or almost plastic-like to the point of discomfort.  The need for quality recording with these headphones cannot be stressed enough.  Even slightly critical listening will make poorly-recorded music an exercise in masochism. 
Conclusion
 The Q701s are cold, detailed, energetic and sometimes sibilant.  Comfort is okay, but you get a lot for your money.  If you love classical music, jazz and female vocals and have some SACDs or a sizable FLAC library you'll love 'em.  If you have a more varied library, you'd do well to have a fun, bassy headphone (say, the V-Moda M100s) to pair with the Q701s.  Either that, or keep the Q701s as a bit of extra flavor with a lusher pair when you're feeling more critical or really want to hear John Coltrane sweating in 'A Love Supreme'.
 

After about a year of owning the Nuforce Icon HDP, I decided to upgrade my Amp/DAC to a unit more suited for the LCD-2's needs.  Having combed through the Amp Recommendations thread for the LCD-2, I decided upon the NFB-10SE.  Once everything with Paypal cleared and I finally got it from China, I was treated to musical bliss.
Design:  This amp is fairly large.  It's (WxDxH) 9x21x3 inches (22.8 x 53.4 x 7 centimeters), so you should have a good bit of space cleared for it.  For being quite large, it's surprisingly light.  This doesn't mean it feels dainty, mind you, it's very solidly built of metal.  It's all black with silver buttons on the front panel, which has some clear LEDs.  There's 9 filters (the last few are limited to 16/44), and I've found 3 to be the best for the LCD-2.  You can select high or low gain, three data inputs (USB, Optical and Coax) and a digital volume from 00 to 48.  It has balanced as well as single ended inputs, which can push 10W and 3.3W for 25 ohms respectively.  I've not used the balanced option, but the SE works just fine.  
Sound:  It's very slightly on the bright side of neutral, but nonetheless quite smooth and musical.  Every single detail in the music is revealed but not forced on you, and the instrument separation is fantastic.  With this much power on tap, it can really bring out the potential of the LCD-2.  The bass is less prominent, albeit much more refined and articulate.  The mids are smooth, well-defined and have excellent texture.  As it's a very slightly bright amp, some highs might be a little harsh on poor recordings, but otherwise it's 100% groovy.  In general, it's best to have a lot of good recordings, because it is manifestly not a forgiving unit.  The NFB will make it very clear what quality you're giving it. However, if you feed it well-recorded material and don't use Grados (which can be sometimes sibilant), I can guarantee musical bliss across the board.  These are a perfect match for dark, laid-back headphones.  I don't recommend using Grados or Ultrasones, since bright + bright = pain.  But if you have a pair of LCD-2s and want world-class sound without dropping a grand, the NFB is your best bet.
Value: The amp/DAC itself costs $500 before shipping, which is nothing to scoff about.  It is nonetheless an incredible value.  I tried a Lyr/Bifrost combo with my LCD-2 and thought nothing could be better.  The NFB proved me incorrect, and for $300 less.  A quality amp for quality sound.

  Early this year I saw what I thought must have been providence: A pair of Denon Ah-D7000s for $600 from a reputable dealer.  I had been doing a fair amount of research into the upper-tier of flagships: LCD-2, HD800, T1, Ed 8, etc.  When I saw the Denons, I knew these would be the headphones for me.  And after opening the box and viewing my new mahogany headphones, I was 100% correct.  For 8 months these headphones spent several hours a day on my head, giving me musical bliss.  Note: these were fed with a Nuforce Icon HDP DAC, which I highly recommend for them.  And here's why:

 Comfort and Design: The Denons disappear on your head like no other headphone can.  I've never once encountered a pair of high-end cans that were so comfortable to wear, especially for somebody with a big head like me.  Not only are they comfortable, they're gorgeous: piano-glossed mahogany wood cups with leather pads and headband.  They're very simple, but also very elegant.  If the LCD-2s - which replaced the Denons - were this comfortable, I would be permanently satisfied with my headphone set-up.
  On to the sound!
 Highs: Being bright and warm, the highs on the Denons are actually very good.  They're natural and focused, and sound amazing for pretty much any good recording.  Female vocals and electronic music are smooth and pleasant.  Although the highs aren't the highlight of the headphone, I can definitely say if you listen to music with a lot of the high-range, you won't be disappointed.  String music is lifelike, detailed and all around incredibly enjoyable.
  Mids: If you're coming from a pair of mid-tier headphones, you won't notice how recessed the mids are.  However, after comparing them to the LCD-2s, the mids are definitely recessed.  You can see this on the FR graph, but how good are the mids?  I would say they occasionally suffer with music that also incorporates a lot of low-range music, since that seems to be their focus, but on their own the mids are excellent.  Vocals are sweet and intimate, and everything feels real in vocal-intense recordings.
 Bass: Oh the sweet bass.  If you love electronic music, the Denon will be your go-to headphones.  The bass is smooth, impactful and sweet.  Percussion music is wonderfully refined and in-your-face, dubstep is otherworldly and heavy metal is beautiful.  I cannot recommend these headphones enough for a bass-head.  Out of the entire spectrum, this is the range the Denons do best.  It reaches extremely low and provides some great texturing.  One might expect this with fun headphones, but I definitely don't regret the Denons being fun.
 Presence and Transparency: One of the things the Denons also excel at producing is presence.  Every note feels distinct, clear and powerful.  This may very well come with the Denons just being powerhouses for the highs and lows, but overall I think the Denons have a very special flavor concerning presence.  As I stated in the bass section, percussion music is phenomenal with these headphones.  If you love hard-hitting music, you can't possibly go wrong with these.  However, when considering presence, one must also consider transparency.  Being fun headphones, transparency doesn't seem to be as much a focus, and (may) have something to do with a closed design.  I'm not an audio engineer, so I don't know.  But coming from the Denons to the LCD-2s, there seems to be a very thin space between the music and the listener.  It's almost unrecognizable until you actually do a thorough comparison between the headphones, but the transparency certainly suffers from the flavor of the headphone.
 Soundstage: The headphones are of a closed design, so the soundstage simply won't be as good as other open flagships.  However!  The soundstage is still very good.  Music has a brilliant intimacy, and everything is defined very clearly in space.  There's no 'blob' with the Denons by any stretch, so long as you don't expect them to be soundstage-focused.  I can't really expect a pair of fun, closed headphones to compete with the HD-800s or T1s, especially considering that they do everything else very well.
 On a comparison with the LCD-2: As I stated in my review of the LCD-2s, when buying the LCD-2s I intended to make a decision between them and the D7000s.  I eventually chose to sell the Denons, but I must add how difficult it was.  The problem in choosing between either headphones arose in a very strange manner: they're simply different.  The D7000s are excellent headphones, and had been my absolute favorite for 8 months. I've heard the 600 models from Sennheiser, the Thunderpants, DT880 and Dt990s, but I didn't love any of them like I love the D7000s.  It was merely that the LCD-2s don't have any faults concerning SQ.  When switching between the D7000s and LCD-2s, it became increasingly apparent that they were both excellent but nothing - excluding naturalness, transparency and soundstage - was starkly better or worse in either.  That being said, I still find the LCD-2s as the natural upgrade for somebody who loves the D7000s.  I must still recommend a degree of scrutiny when choosing which stays or goes, since the LCD-2s are several hundred dollars more expensive and scale much better with more power.
Conclusion: The D7000s are an excellent pair of flagship headphones.  They're elegant in design, amazingly comfortable, and provide an extremely pleasant listening experience.  The bass and highs are wonderful, but the mids and transparency leave something to be desired.  However, they are definitely affordable in terms of flagships, and if you're somebody who loves fun headphones and doesn't have the scratch for a pair of LCD-2s or T1s, go for the D7000.  You won't be disappointed.

I would like to preface this by saying I've not had the kind of time I had with my Denon AH-D7000s - which were my favorite headphones that got almost 100% of head-time and hundreds of hours of use - as I have with my LCD-2s.  However, I shall be using them as the basis of comparison since I found - and still find - the D7000s to be an amazing pair of headphones, especially for their price point.  I bought these headphones at the beginning of September with the intention of getting a sample of their sound and perhaps even making them my top choice of headphone.  For the sake of reference, I was using a Nuforce Icon HDP as a DAC and amp.  At this point, I can definitely say they are now my go-to headphones.  On to the review!
Revision: After having spent six months with these headphones, I've come to a few new conclusions that I think are worthy of sharing.  These new conclusions will be based partly on my experiences with the LCD-2s and the Audio GD NFB-10SE - a combo I am loving - and the much extended listening time I've had since the original review.  The revised sections will be marked as such.

Packaging and Design 
   This was the most over-packaged headphone I've ever bought.  It was in the beautiful wooden box, with foam, inside of another cardboard box, inside of a larger cardboard box.  The box that carries the LCD-2 itself is a dark, polished wood with the Audez'e logo on the bottom right of the lid.  Inside is red silk(?), and some foam on the inside of the lid to protect the LCD-2s.  The LCD 2s smelled strongly of Oak - due to the wood polish, I presume - and leather.  The headphones themselves are extremely sturdy and heavy (this will be discussed further in the 'comfort and use' section).  These won't be breaking anytime soon.  
   These are completely open, and although very attractive and stylish looking off the head, look absolutely foolish while on the skull.  The headphone jack is a large, silver 1/4 inch (or 6.33 mm) plug with a bit of black rubber that screws on.  Overall, these headphones are sturdy and well-made, but I gave them a half-star less because of the weight and how ridiculous they look on the head.

Comfort and Use
  This seemed to be a point of contention on the LCD-2 thread before it was locked.  I will admit it's a bit of hit-and-miss in terms of comfort, but I found having the large back end of the leather pads sitting at the point where the jaw meets the neck is prime.  These aren't nearly as comfortable as my Denon D7000s - which disappear on the head without question -, but for somebody with an enormous noggin' (I have to adjust it almost all the way up) it's not so bad.  If you have a small head and/or neck, you'll have to get adjusted to the heftiness of the LCD-2s.  The clamp force is a measure greater than what I expected or am used to, which may become an issue depending on the music you're listening to or how long you use them.

Sound
     
     Highs:  The highs on the LCD-2s are brilliant.  The Beyer Dt990s up until hearing the LCD-2s had the best highs I had ever heard, especially paired with a warm amp.  However, once listening to Dream Theater, Rush, and various classical music, I have found a clear winner.  Sibilant is not even in the same building as these headphones.  Cymbals and hi-hats are perfectly crisp, high vocals are engaging and wonderful.  There is absolutely no artificial tonality to these headphones.  It feels as if the singer is in the room with you as the music plays.  I used to think the Denons had natural-sounding highs, but the LCD-2s are far superior.  A word of advice, though:  these headphones, like most, shine when given proper recording.  Give it a 128 kbps, and you won't feel the magic.  I can definitely say the mids and bass on these cans are definitely their strong point, but the highs are certainly no slouch.
     Revision: The highs are heavily dependent on how well textured the amp or source is.  My Nuforce is a bit laid back, at least in comparison with my NFB, so the highs weren't as articulate as they could be. With the NFB, the highs are distinct and well-articulated, but it seems to bring the highs themselves closer to an in-your-face Grado signature.  The strengths of the LCD-2 highs - natural, non-sibilant and engaging - were amplified, but very occasionally the highs were striding the fence on sibilant.  
     Mids:  The crown prince of mids has earned his title.  The vocals are never harsh, or artificial.  Every note is sweet and perfectly executed.  "Spanish Harlem", a song I've noticed thrown around a lot as a benchmark for engaging mids, sounds mesmerizing on these headphones.  It's like Rebecca Pidgeon is whispering into your ear the entire song.  Voice has a very live, natural quality to it.  I had never realized how recessed the midrange had been on my Denons or M50s until having heard these.  Listening to the song "Autumn Serenade" from "Standards" is stunning.  The Denons have sweet, engaging vocals, but the LCD-2s bring life and naturalness to singing in a way no other headphone can.  Another song by Livingston Taylor, "Grandma's Hands", is conveyed with a natural energy that I've yet to hear again.  There is no negative to the mids.  If you enjoy mids, go for a pair of LCD-2s.  You will not be disappointed by any means.
    Revision: The mids are, and remain to be, the strength of the LCD-2s.  In general, the NFB provides a lot more power and articulation than the Nuforce did, which lends better distinction to the vocals.  This shouldn't be mistaken for emphasis or edginess.  Mid-range clarity and naturalness is merely enhanced, as if the singer cleared their throat and gave it some extra oomph.
   Bass:  The bass of the LCD-2s does not have the impact of my D7000s, by any stretch.  That is something you will notice immediately coming from a pair of fun and bassy headphones to these.  Although it doesn't have as much impact as a pair of D7000s, it certainly has plenty of impact to spare.  With the song "Slam" by Pendulum, the first minute or so of the song can be a challenge for a headphone to really deliver the kind of 'Slam' for which the song is titled.  The LCD-2s do so perfectly, and with a refinement that trumps the Denons.  A very good test of bass is the song "Failure in the Flesh" by Through the Eyes of the Dead, which can also be challenging for a headphone to do properly.  On the LCD-2s, the drum notes and vocals have a beautiful union of force and refinement.   There is no muddiness whatsoever, no matter how low or how strong the bass goes.  The bass on these beauties is liquid, refined and extended.
    Revision: As with the mids, the bass isn't necessarily emphasized over the rest of the frequency range.  Everything in the lower end is just better articulated, textured and powered over the Nuforce's performance.  I would also compare the change in signature from the Nuforce to NFB with leaning towards the AKG, but the bass proves this not to be.  Bass notes are tighter, punchier and faster, but still fast and natural.  
    Soundstage:  Oh yes, soundstage.  Most closed headphones simply can't compete with open headphones in terms of soundstage, and the LCD-2s don't make me disbelieve this.  The soundstage is much wider than my Denons - which I believe is again from the open design -, and much deeper.  All the notes feel as if they're placed accurately and distinctly in space.  Listen to any drum-heavy song, and you'll understand what it really means to feel the music.  "Festival De Teum" feels down right ethereal through these cans.  If that choir is 10 feet above you, and thirty feet forward, you'll definitely know it with these headphones.
   Revision: Not much to say here, but I definitely feel like soundstage was improved.  This might be because presence and transience are far improved, so each note feels distinct in space, but I do believe depth is noticeably better.
   Presence and Transience:  One of my problems with choosing which headphone stays or goes was how different the presentation was between the Denons and LCD-2s.  The D7000s have, hands-down, some of the best instrument separation and presence I've ever heard.  However, after a lot of listening to the LCD-2s, I've decided I prefer them.  Everything is transparent and clear through these headphones, which was a caveat for the Denons.  As with soundstage, any drum-heavy track will reveal just how well these headphones do Presence, and how quickly.  The Dt990s are the fastest headphones I've ever heard by far, but the LCD-2s aren't too far behind.  Cymbals have a crisp, clean quality, and every note feels distinct.
   Revision: If you had a problem with the LCD-2's presence and transience, the NFB will fix it in kind.  Every single part of the music is distinct, clear and clean.  This might be the largest improvement I heard from the NFB, and generally brings the LCD-2s closer to the Grados or AKGs in this respect.  Heavy metal, rock and classical all benefit extremely well from this enhancement.  It's almost as if the LCD-2s were veiled with the Nuforce, and now it's being set free by the change in source/amp.
 Conclusion:  These are all around the best headphones I've ever heard.  Nothing sounds bad on them, and everything feels natural, transparent and liquid.  According to the FR graph, these headphones are reasonably neutral, and I have to agree.  They're not bottom-heavy like my Denons were, or too focused in the mids and highs like I find my Grado Sr-80s.  They're not as comfortable as my Denons by a large margin, and might cause some fatigue after extended listening.  When properly amped, they can deliver sweet musical bliss.  I only have experience with the Meier Opera and Nuforce Icon HDP, but the Amp Recommendations thread has impressions for every amp under the sun with these.  Overall, I would definitely recommend this to any headphone user (if you have $1000 to drop) with a proper amp and a large cranium.
  Revision: The LCD-2s are truly chameleons in the way they respond to changes in amps.  The sound signature remains slightly dark, and their strengths are the same - transparency, clarity, midrange, naturalness, etc. - but each amp seems to add its flavor to the headphones themselves.  I wouldn't say it's drastic, as with the Paradox t50 mods, but it's certainly noticeable.