It's time for another review that I've been sitting on for a while. Writing a review of a vintage headphone is difficult at the best of times, and there are some strange features of the AKG K340 that are even more difficult to deal with. Nobody is sure whether there are several different runs of the headphones with different sonic signatures. They are notoriously difficult to drive properly, and many of them have now been modded to various extent. All of that in mind, I suppose this will have to be a review of MY K340s. Others will probably be at least somewhat different.
 
I know precious little about the history of my pair. I know someone has been under the hood, because the pleather pads have been replaced with velours, they have been recabled and terminated with a 1/4" Neutrik plug. A quick peek under the pads reveal that the screen mod has been done as well, because there is no plastic mesh between the pads and the driver. The elastics still have a bit of pull as well--enough to keep them relatively stable on my head. These changes have likely made minor changes to the sound.
 
While the K340 is a bit heavy, they sit quite comfortably on my head. I really like the self-adjusting system that AKG has, because I find it keeps the right amount of pressure on the top of the head and the ears. I can wear these for quite a while without them being uncomfortable. The new nylon-covered cable is slightly microphonic, but I don't see that as a huge problem since these are hardly headphones I wear while on the go.
 
All reports about the K340 being hard to drive well should be respected. I am not impressed by the sound I get from them out of most of my sources. They only really shine through my Musical Paradise MP-301 tube amp. For the purposes of this review, I am using FLAC in Foobar bitstreamed into my M-Audio Delta 2496, with RCA cables feeding directly into the MP-301. For those who care, I've got NOS Jan GE tubes in the preamp, and Tung-Sol 6V6GT as amp tubes. It's a good combination with the K340.
 
Now that all that's out of the way, I can get talking about the sound. To be up front right away, these are not my best sounding headphones from a technical standpoint. My DT990/600s dance around them in just about every area, as do my DT150, Kees modded Pro 750s, and maybe even Fostex T50RP.
 
Here's the thing, though. The AKG K340 is a fantastically easy headphone to listen to. They are so musical and so well-rounded that they've gotten quite a bit of head time lately, and never fail to get my feet tapping. They are truly incredible all-rounders, once they are fed the kind of signal they crave.
 
I suspect I have the bass-heavy version, as they have proven time and time again that they are capable of delivering plenty of low-end grunt. Massive Attack's Angel remains my primary bass test track, and while the K340 doesn't dive quite as deep as some of the headphones in my collection, it creates a delightful sense of space at the low end, which doesn't diminish as the rest of the song develops above it. It lacks some of the punch of my Beyerdynamic cans in the low end, and I understand the criticism that some have that the K340 tend to have flabby bass. That softness is emphasized more in Rock and Soul, where the low end has a tendency to get a bit muddled. It's not a deal-breaker, but it is probably the weakest point in the sound. What the bass lacks in tightness, however, it makes up for in quantity. It's very easy to follow bass lines with these headphones.
 
The slightly slower speed of the dynamic drivers persists a bit into the midrange. I can't complain too much, though, because it's all so incredibly musical. Vocals, guitar, and piano all sound spectacular on these headphones. It's what AKG is known for, and they really nail it here. I played a few tracks by Fiona Apple, Jeff Buckley and Sharon Jones to focus on vocals. In each track, the vocals are emphasized nicely, and are emphasized without being too forward. The K340 seems to add very little coloration to the midrange, as some vocals sound warm and cool depending on the source. Overall, the signature is quite warm, though.
 
The treble in the K340, for those who don't know, is handled by an electret driver that functions along with the dynamic driver. This is a bit paradoxical, because while the bass and midrange aren't especially fast, the electret driver delivers lightening quick treble. This is an odd effect in tracks like Angel, because the high end speed exists in opposition to the slightly slower bottom end. It creates an illusion of speed throughout the sound spectrum, and it really is awesome treble. It is fast, bright and sparkly, without ever threatening sibilance or sharpness. It's great for electronic music, but also adds quite a bit to rock music. I could never really get into the sound of the AKG K240M that I had, which was similar through the rest of the spectrum, because of the rolled off highs. The electret driver adds a magical top end to the K340 that makes it much more appealing.
 
The interesting and unique sonic qualities of the K340 has a side benefit that I've quite enjoyed. These are my most forgiving headphones, once they are connected to a good amp. I've been listening to quite a bit of garage rock revival music lately, thanks to the The Like's Release Me, which is a pretty awesome rock record. It's also not that well recorded. This makes it almost impossible for me to listen to the album with the other headphones in my collection. The DT990/600, even on a tube amp, emphasizes the sibilance and becomes quite unpleasant. I don't even want to talk about how this album sounds on the Ultrasone Pro 750. Meanwhile, the Fostex T50RP lacks the raw energy to do justice to the album. It sounds awesome on the K340s, though, because the bass gets a nice boost, the mids are emphasized without getting ugly, and the brightness helps keep the energy going.
 
It's also a sounds that works with a wide range of genres. Jazz sounds pretty good on them too, though things to have a tendency to get a bit mucky. Mingus Big Band's Moanin' sounds awesome on them, though Dave Brubeck's Time Out asks for a bit more clarity and precision. Orchestral music is stunning, revealing a slightly wider soundstage than expected, and an overall dynamic signature.
 
And, in the end, I think that's what the AKG K340 is all about. If you have a tube amp and are looking for a pair of headphones that will be musical, fun, and completely unfatiguing, it would be hard to do any better than tracking down a pair of this unique vintage oddballs. They won't deliver you razor-sharp clarity or studio-use neutrality, but I find myself getting lost in the music, and that's what this hobby is really all about, right?
 
Right.

As the Ultrasone Pro 750 arrived, I really wanted to like them.  After all, these headphones embody just about everything I've claimed to like in the past few months of acquisition and experimentation with various headphones.  They have a very balanced sound signature, they are detailed, and bright rather than dark.  I was waiting for that Ultrasone bass that I kept hearing about, and I was prepared to give them enough time to really get a sense of them.

Well, it's been over a week, and I've put quite a few hours on the 750s.  Do I like them?  I'm still not sure.  There are a lot of things I like about them, but there are some troubling areas as well.

I really like the build quality and packaging.  It's great to have a choice between the coiled and straight cord, the headphones themselves are well-built without feeling bulky, I find I can wear them comfortably for hours, they have the right amount of clamping pressure, and the replacement pads are a nice touch.  The hard case will definitely keep them safe when not in use, and I'd really like to see more companies include a good transportation option.

On a first listen, though, I was a lot less impressed.  As I've already said, I like bright headphones.  I got rid of the Shure SRH-840 because I found them bland.  I like the Beyer DT-990 Pros and never found them too harsh.  None of this prepared me for the sharpness that is Ultrasone treble.  My first impression was that sharp glass was being jammed into my ears.  I gave them some time, because I knew it might just need some further breaking in or that perhaps I would just need to spend some time getting used to the overall sound signature.  For a few days, I kept trying, and was getting increasingly frustrated.  I couldn't begin to understand why anyone would like this sound.

One afternoon, I was in the basement with my laptop, and I didn't have my usual amp setup--just my humble Hotaudio Bitperfect.  Although it's not the best amp in my inventory, it is significantly warmer than my other sources, and it made a huge difference.  The warmth of this amp cut the edge off the treble, and brought a bit of warmth to the midrange.  Suddenly, the 750's sound signature started to make a bit more sense.  The rest of the review is written as the headphones sound out of a warm source.  I still can't listen to these cans out of my custom DAC/Amp, which sounds better for all of my other headphones.

There's no question, these are still treble-heavy cans.  What consistently impresses me is their detail retrieval.  Even when stacked up against the DT990/600, the DT150, and Fostex T50RP, the Ultrasones consistently reveal details that the other headphones obscure.  I've never heard cymbals like this, and they create a truly impressive feeling of sparkle and space around instruments and vocalists.  When I use Massive Attack's Angel as a test track, it's always the bass that stands out.  With the Pro 750, the bass is there, but what really stands out is the clarity and punch of the drums.  That clarity and punch is true of other instruments as well.  I used to play trombone in jazz bands, which means I stood right in front of rows of trumpets.  Loading up tracks like The Mingus Big Band's Wednesday Night Prayer Meeting reminded me exactly how that used to sound.  They make trumpets and alto saxes sound spectacular.  These are hugely energetic headphones.

Detractors of the Ultrasone sound always talk about the metallic midrange, and it's a fair criticism.  That brightness that creates such clarity and punch in the high end also draws warmth out of the midrange, where it's needed most.  Jeff Buckley's Lilac Wine is one of my other test tracks, and while the Ultrasones do a great job of creating space between the instruments, it doesn't showcase his voice as well as some of my other headphones.  This is a bigger problem for female vocals.  Fiona Apple's voice should sound rich and warm, not sharp.  Ironically, what isn't perfect for vocals proves to be excellent with both piano and guitar, though, and it makes me wonder if I'm not just used to warmth being added by most headphones.

The Pro 750s have exceptional bass, but it's also very balanced.  That means these are definitely not the Ultrasones to recommend to serious bassheads.  In tracks with lots of bass, the Pro 750 delivers with ease, diving as deep as the track demands.  They lack the muscle of the Beyerdynamics at the bottom end, but deliver some of the tightest bass I've heard.  Even with low electronic bass, individual notes are always clear.  They pass both the Angel test and The Chemical Brothers' Under the Influence test with ease.  Still, with both these tracks, by the time the bass is up where I want it to be, I find myself overwhelmed by the bright treble.  The bass is a reminder that these are meant to be studio tools, not DJ headphones and not for casual listening.

The other big question with Ultrasones is whether or not the S-Logic works.  For me, the answer is "sort of".  The effect is surprisingly subtle, and does place the sound slightly outside the skull, but certainly doesn't perform any magic.  I think people go in expecting the S-Logic to live up to the marketing hype, and it really doesn't.  It's just another way to create a slightly more open sound from a closed pair of headphones.

I have a few other things I want to make sure make it into this review for people who are curious about the 750.  First, their ability to resolve detail makes them extremely source-dependent.  They sound like total crap on tracks that were poorly mastered, and they reveal compression in low-bitrate MP3s better than any other pair of headphones I've ever put on.  These are a bad choice for anyone who is unwilling to commit to seeking out high quality copies of well-mastered music.  Pop music that suffers from the loudness wars are particularly painful--keep these headphones far away from contemporary radio pop.

In addition to being source-dependant, I've already pointed out that they are quite amp-dependant.  They sound unbearable out of my custom DAC/Amp, unpleasant out of my Cute Battery II, and completely wrong out of the Musical Paradise tube amp.  I had high hopes for that combination because of the warmth of the tubes, but no luck.  They sound better from my Yamaha Home Theatre receiver, but best out of the Hotaudio Bitperfect, which I can't say is true of any of the other cans I own.  I also usually hate software sound modification.  I almost never use equalizers, dislike crossfeed effects, and always find software virtualization just muddies up the sound.  Strangely enough, I find that the Izotope Ozone plugin for Winamp really improves the overall tone of the Pro 750s, which means they respond quite well to equalization.  I'd be interested to know what percentage of Ultrasone owners use software mods compared to fans of other brands.

They also don't isolate particularly well for closed headphones.  Even at moderate listening levels, these leak quite a bit of noise, especially when taken off.  They don't leak as much as Grados, of course, but I wouldn't use these if you need to wear headphones next to someone that's trying to sleep.

Again, the Pro 750s make for a tough recommendation.  It's taken a week, but I am starting to hear what makes these headphones so polarizing.  I understand why Ultrasone spawns rabid fanboy enthusiasm, because I've never heard clarity quite like this, especially from dynamic headphones.  They are bold, brash and uncompromising, and I suspect that getting too used to this sound would spoil you for most other brands.  I also understand why some people have described these as the worst headphones they've ever heard.  They are sharp and icy cold, and I find they take getting used to every time I've been listening to other headphones.  After listening to them for an hour, though, they make most of my other headphones sound muddy and flabby, which is actually pretty impressive.  I'm not trying to say that either side of this debate is right, but I will say that we won't see this argument go away any time soon.

For now, I'm going to hang on to the 750s.  They do some things stunningly well, and even though they are never easy headphones to listen to, they are magical with certain tracks.  I'm not sure yet whether they will be a permanent addition to my collection, but I at least admire how uncompromising Ultrasone were when they designed these.  Will you like them?  Your guess is as good as mine.  Do everything you can to hear a pair before you drop the money on them, though, because there are definitely no guarantees.
 

---

I am doing a quick follow-up.  Last week, I completed the well-documented Kees mod on the Ultrasone Pro 750, and I'm pleased to say it has made an absolute world of difference.  The bass has been brought out a bit, the mids have been sweetened, and it tamed the highs nicely.  They are still very cold headphones, but are now genuinely enjoyable with almost every track I've tried them with.  They have maintained their analytical qualities and balance, and could now be used for professional monitoring and mixing if needed.  Because of the ease of modding these, I have adjusted my score accordingly.

 
The orthodynamic club at Head-fi probably feels a little outspoken at times. They have a less common headphone technology that they believe very strongly is fundamentally superior to the traditional dynamic drivers that we see so often. The dauntingly enormous orthodynamic roundup thread is a testament to the dedication and passion of this Head-fi subculture. To make matters worse, there are very few companies still producing orthos. There are some hugely expensive offerings, but only one brand making affordable offerings. That company is Fostex, though many consider the new flagship T50RP to be inferior to some of the vintage orthos from the '70s.
 
I am not an expert on orthos by any stretch of the imagination, but I was intrigued by the discussions in that thread. The Fostex T50RP are not really that cheap, so I decided to give them a shot.
 
I'm glad I did.
 
Some of the rumours about the T50RP are true. They don't have strong bass, and they are very neutral and balanced. Anyone who is really into the Grado sound or any other hi-fi sound signature can just stop reading now. For those who like a more neutral presentation, however, these really do offer something special for a bargain price. I've been putting mine through their paces for a few weeks now, and I'm driving them from my Yamaha Home Theatre receiver, and custom built Texas Instruments DAC/AMP.
 
Ask any ortho fan what makes them better than dynamic headphones, and they will talk about the smooth, beautiful midrange and an incredible transient speed. This is the paradoxical mystery of the T50RP, because they manage to be capable of enveloping warmth, but also painstakingly detailed and precise. Jeff Buckley's Lilac Wine is one of my main test tracks for vocals, and I've rarely heard him sound better. The T50RP brings out the tone of his voice beautifully, and places it just where it should be in the soundstage. That midrange does stunning things for guitar and piano as well, where the speed and accuracy create some truly beautiful music.
 
Of course, at this price we expect some compromise. In this case, that stunning midrange comes at the cost of some extension at both ends of the sound spectrum. With the new earpads (replaced in the lineup a couple years ago), I wouldn't call these bass light compared to a few of my cans, but they lack the punch and depth I've found in my DT990s and DT150s. Massive Attack's Angel does have a reasonable amount of bass, but it is genuinely balanced and never threatens to overwhelm. It lacks definition, though, and doesn't have the velvety texture of the DT990s.
 
The same is true of a rolling off at the high end. Treble is certainly present when it's found in the recording, but cymbals don't have the sharp sizzle that Beyerdynamic cans demonstrate. For people who hate sibilance more than anything else, this is a good thing. It takes away some of the space in recordings, though, and although Buckley's voice sounds spectacular on these cans, the track doesn't have the air around it that it does on some of my other headphones. It's overall fairly forgiving on harsh recordings, though, which is more than I can say for my Beyerdynamic cans. As a side note, the same is not true of low bitrate recordings, which sound terrible on the Fostex headphones.
 
On Head-fi, we often talk about headphones that melt into the background. The Fostex T50RP are the best cans for this I have ever owned. If I feed them with bright Queen recordings, that brightness comes through with speed and energy. If I toss some Chemical Brothers at them, they push out a bass sweep that never stops dipping lower. Rock music has punch, Soul is laid back and groovy, jazz recordings are light and airy... these work pretty well for almost anything. The first time I put these on, everything felt strange and a bit different. After some time adjusting, though, everything feels just about right.
 
There are times that I'm in the mood for other things, and that prevents the T50RP from being my ultimate headphones. Sometimes, I want more bass than I can get from these things stock. There are other times that I want something a bit more musical and aggressive. Still, if I want to hear what a track really sounds like, the T50RP is the headphone I reach for every time.
 
Of course, there's more to a pair of headphones than just the sound. These are also some of the most comfortable headphones I own. Once I found the right adjustment with the headband, I find the fit of these is just about perfect for me. There's a point of contact at the top of my head that holds them in place, and since it's rubber, it never slips out of place. There is very little side pressure, just enough to get a seal over my ears. I can wear these for hours without any discomfort, which makes them even better as professional audio tools.
 
With the T50RP, it is important to talk about driving them as well. These are not easy cans to drive. Looking at the specs (50ohm impedance and sensitivity in the high 90s), these shouldn't be especially hard to drive, but they sound terrible without plenty of juice. Portable players are right out, and they don't sound good out of my Hotaudio Bitperfect, either. The good side of this is that they will take an astonishing amount of power if plugged into an amp that can supply it. Another peek at the specs reveals that these are rated to handle up to 3000mW, which is borderline absurd. While you would never actually want to put that kind of current into a pair of headphones, it means that these drivers will not distort, even when pushed past what any headphone should be asked to dish out. Of course, that doesn't mean I recommend playing these at 130dB, but apparently they can do it if your ears can.
 
I can see how many people have been unimpressed with these headphones during an initial audition. They didn't sound right to my ears, and I find I still have a five minute adjustment period every time I put them on. Once my ears adjust, though, I really enjoy these headphones with almost any music. That, alone, makes them well worth the asking price. If you haven't yet dabbled in the fringe Head-fi experience of orthodynamics, it just might be time you did.

 
I have been recommending these cans quite frequently over the past month or two on Head-fi, but I have yet to get a review of them up. This is my attempt to rectify that situation.
 
Ordinarily, if you want a pair of DBI Pro 700, you need to shell out about $200 directly from the company. They are primarily designed for use in music store listening stations, and one looks explains why. The cable is reinforced with rubberized steel, the entire casing is coated in plastic, and the driver is covered with a metal plate with holes. They are the same casings that German Maestro uses in their indestructible line, but DBI pro puts in their own copper-plated aluminum drivers, which gives them a very different sound signature.
 
When my pair first arrived, I noticed a few things. First, these are actually quite light. The cable is heavier than the headphones themselves, and they are unexpectedly comfortable. This comfort has increased as they've settled in, and they managed to get a decent seal with minimal discomfort. The cable is long enough to use with a portable player, or at a desk. I did find the pads were fairly shallow, which meant my ears pushed a little against the dustproof fabric. I have since replaced them with Beyerdynamic DT770 softskin pads, which haven't affected the sound significantly, but are more comfortable.
 
I have listened to the DBI Pro 700 quite a bit now, since they are my primary work headphones. I can throw them in my bag without worrying that they will be damaged. They isolate as well as any headphones I own, and they have a quite interesting sound signature, which I think is thanks to the metal drivers.
 
Coming from a pair of German Maestro cans, I was expecting a similar sound signature: light accurate bass, a wide airy soundstage, and a delicate midrange. Evidently the drivers make a big difference, because the DBI Pro 700 are almost the polar opposite of my German Maestro 450 Pros. The first thing that jumped out at me was bass. Lots of bass. Deep, rich, powerful bass. DBI claims that the difference between the 700 and 705 is that the 705 has increased bass response. I assure you, that doesn't mean that the 700 is bass light in any way. These handle Massive Attack's Angel with ease, with silky yet punchy waves of bass. They do just as well with The Chemical Brothers' Under the Influence, a song that forces many headphones to give out on those bass sweeps. Of course, monstrous bass is only good if it's under control. I also use Damien Rice's The Blower's Daughter to test bass, because uncontrolled bass hits much too hard when it arrives in the second verse. Here, there is not too much trouble, yet I wouldn't recommend these for people who primarily listen to jazz and classical.
 
Often, the real sacrifice with bassy cans comes in the midrange. Vocals and instruments get drowned out by a wall of bass that impresses at first but quickly becomes fatiguing. This is where the metal drivers really come into play with the DBI Pro 700. These cans do wonderful things with vocals. They manage to be quite balanced and accurate, while remaining quite aggressive. Jeff Buckley's Lilac Wine is almost always my first test track with new headphones, and his voice is incredible through these cans. They aren't as prominent as they are through some of my other headphones (especially the DT480), but astonishing for such aggressive headphones. A quick spin of Fiona Apple's Tymps shows that they handle female vocals just as well. Great piano and guitar as well.
 
As far as highs are concerned, I'd call the DBI Pro 700 nicely balanced. I don't like warm headphones, and I don't find these too rolled off at the upper end. At the same time, these don't display the same brightness as the Beyers I own, so there is never a hint of sibillance. As much as I love my DT990s, they get pretty harsh on poor recordings. That never happens with the DBIs.
 
"But wait," you say, "are these perfect headphones?" Well, not necessarily. Everything comes with a cost. In this case, there are a few things that will turn off some listeners. First, the bassiness can get a bit overwhelming. I wouldn't hesitate to recommend them for rock and electronic genres, but they just don't sound natural for jazz and classical. Like Grados, the DBI Pros have a fairly narrow and aggressive sound stage. I did listen through Miles Davis' So What, though, and aside from a bit too much bass resonance, they sound pretty good. It also means they aren't especially refined. They rock hard, and refuse to apologize for it.
 
For $200, the DBI Pro hit a lot of right notes. They are punchy, accurate, fast, and aggressive. They have a nicely balanced signature and a pretty unique sound. They aren't perfect, but they are some of the best closed all-rounders I've heard. They benefit from some amplification, but they sound decent coming out of a portable player as well (a bit of that bass and clarity is lost)
 
But here's the crazy thing: When they pop up on Ebay, they don't sell for $200. They usually sell for around $40, which is not just a good deal--it's an insanely crazy good deal. These are headphones that sit with pride on the same table as my Beyerdynamic DT150, DT990/600, and Fostex T50RP. I would listen to these over my sold Grado 125i and Shure 840s on just about every recording. In fact, I'm pretty sold that $40 for these is the best possible bargain to be found in the headphone world. Grab a pair, and set up your own personal listening station.

I'm really only half a year into my serious headphone journey, which began when I got a pair of Shure SRH-840 and Grado 125i at around the same time, along with a solid custom headphone amp (which never ceases to amaze me) from my brother-in-law.  Both of those original headphones are gone now, but the journey has taught me a lot about my own tastes, pushing me ever closer to a pair of headphones that I would be happy with for the long term.
 
That pair is the Beyerdynamic DT-150.
 
Before starting, I'll go through a few things that I've learned in this journey, and how the DT-150 fits into those lessons:
 
1. Professionals know what they're doing.
I have found myself increasingly gravitating towards studio-driven products, and now all of my headphones are geared for professional use.  I believe strongly that this is where the deals are, and the DT-150 fits into that category.  All the money you spend goes into sound quality and build quality, and none of it is wasted on bling that most people would laugh at anyway.
 
2. Balance is important.
I am not a basshead, but I do like impactful bass.  Midrange is where the real magic is, and it shouldn't be sacrificed.  Highs are what gives music brightness, speed, and sparkle.  That's why the Grados are gone, and that's why the Beyerdynamic DT-990 Pros don't get much head time anymore.  The DT-150s reveal exactly what's in the music.
 
3. Musicality is even more important.
In theory and on first listen, the Shure 840s do a great job with lesson #2.  They just weren't that engaging, though, and a level of aggressiveness, responsiveness and musicality is just as importance as balance.  This is the danger with studio headphones, and it's one that the DT-150 avoids with ease.
 
After a month of listening to these headphones, I find myself a bit amazed that they haven't gotten more positive attention around here.  The buzz has been positive overall, but it's been awfully quiet.  
 
The headphones themselves are big, bulky, and feel like they could take a bullet.  All of the cables and parts are possible to replace, which is nice in an industry with so many stories about cables that disconnect, wood that cracks, and ear cups that fall off.  They do clamp fairly tightly, but I don't find them horribly uncomfortable.  I can certainly wear them for hours without problems, but I know a lot of people have found them less comfortable--definitely rule them out if you have glasses with thick frames or frames that stand out from the sides of your head.  Thanks to all the pleather, they do get sweaty as well.
 
Thankfully, the sound is absolutely sublime.  The DT-150s were originally made to build on the design of the classic DT-100, but with added bass response.  The design team definitely succeeded on that front.  I wouldn't necessarily call the DT-150s bass monsters, but they are happy to supply whatever level of bass recorded on music tracks.  They create an impressive sense of pressure on Massive Attack's Angel, which means they have both powerful and deep bass.  Even when the song gets more busy, the bass is still there as well (it gets buried on many other headphones).
 
The mids are equally excellent.  Many Head-fiers with studio experience claim that the DT-250s reflect voices and instruments more accurately, and I can't really comment on that.  What I can say is that the DT-150s showcase vocalists beautifully. They do a great job with guitar and piano as well, revealing minor details and depth that I had rarely heard previously.  The midrange doesn't quite have the sweetness of the GMP 450s, but it's much meatier.
 
The high end also exhibits the signature Beyer brightness, without ever threatening to ascend into harshness and sibilance.   If there is harshness in the recording, the DT-150 will reproduce it faithfully, but it definitely doesn't have the overbearing highs of the DT-990 Pro.  Even though the bottom half of the sound is so rich, it's the high end that prevents them from becoming too dark (I've definitely found that I like a brighter sound, though).
 
I wouldn't describe the DT-150s as either aggressive or laid-back, but they are definitely musical.  The soundstage is nice and wide, and they're highly responsive.  They do a great job with rock, easily wiping the floor with the Shure SRH-840.  They also do a great job with electronic music, movies, and games.  I don't listen to much jazz and classical, but they sound not bad on those genres either.  In the end, it's really the flexibility of the DT-150s that I've been so impressed with.  I wouldn't quite call them a chameleon, because they do have a distinct sound, but they largely stay out of the way of the music and deliver exceptional, well-balanced, engaging sound.  And that's more than enough for me.