For anyone who has read any of my previous reviews on the KRK-KNS 8400, Shure SRH-940, Sennheiser HD448 or Sennheiser PX360, this beginning piece may seem redundant to you.  However, I think it is important to include.  I like to start off by giving the reader a tidbit about my previous audio experience in an effort to put my words into a useful perspective and empower them as a consumer.  Describing my history gives the reader the ability to place a personal value on my impressions and best utilize the information.  With that piece said I hope you enjoy the following and also find it useful.
I’ve appreciated good sound since a relatively young age, and I have my family to blame for it.  I was raised in a household with parents who had a passion for home theater.  Once I started going to school and hearing stuff from other people—and grew older—I began to realize I had been spoiled.  As a result, my standards have been set a little higher and I find my tolerance for low-fi reproduction lower than most.  Naturally I got into car audio once I started driving. I started joining communities like this one, testing and swapping out gear while eventually moving into DIY projects which resulted in a system I still use today.  As the years went on, I then ventured into home audio and landed myself a system through hard work that I am once again proud of and probably won’t modify for some time.  I now find myself in the land of headphones, with just as much curiosity as I had when venturing into the other niches of audio. I find myself building on my knowledge and experience.  Now on to what you came to this page for: the Torque Audio t103z

 
I have been given the privilege to review a pre-production model for the t103z from a new startup audio company, Torque Audio.  Unique to what this unit offers is the ability to adjust the sound to the user's preference.  This seems to be becoming a more popular trend among headphones lately... with the Beyer Custom One and AKG K267 coming to mind.  Torque Audio seems to have approached the idea differently, and in my opinion, more effectively.  The t103z has small filter like pieces which unscrew from the main unit so they can be swapped out.  Torque Audio calls these "TorqueValves", each of which are tuned differently.  The t103z comes with 3 different TorqueValves (Red - Reference; Yellow - Deep Valve; Black - Clear Valve) and Torque Audio has expressed that more TorqueValves will be released later on.  For the sake of this review, I will be addressing the comfort, durability, sound quality of the included TorqueValves.

 
 
Comfort: Look, I'll be straightforward about one thing: I tend to have a bias against buds.  I can't seem to ever get them to fit right and I never find myself preferring them to a full size set for anything other than convenience.  The one exception for me has been the Shure SE535, because that unit fits securely without causing pain, isolates superbly, and sounds pretty impressive.  So take that for what it is involving my comments on the comfort of the t103z.  As is the case with just about any bud, I had to play around with all of the included tips to find out which ones fit best.  Torque Audio includes a small, medium, and large version of a standard tapered cone shaped tip as well as a double flanged tip.  I couldn't get any of the standard tips to feel right or stay in very securely.  I ended up going with the double flanged set, which was strange for me as I usually find those tips useless with other earbuds.  For whatever reason, those were the tips for me with this particular set.  Since fit is everything for buds (regarding sound quality too), all of my notes from here on out involve the use of this particular tip.  Honestly, the t103z doesn't feel so bad in my ear.  I don't start to have any sort of ear canal irritation or pain until roughly the hour and a half or 2 hour mark--in which case a 10 minute break or so would remedy the situation.  They aren't the lightest buds I've tried by any measure, but the cable and inline volume controls don't feel heavy on the ears at all.  Speaking of the cable, Torque Audio did a really good job to make sure it isn't microphonic.  It's a flat style cable that splits in a fixed location into a Y at the inline remote.  As far as I can tell, there are zero microphonic issues, which is a huge plus for those of us that like to strategically run cable.  Anyways, to stay on task... the buds might be adequate comfort wise but they do not fit that securely, at least for me.  This will of course vary from person to person, but in any situation where I am moving quickly in different directions I find myself having the re-secure them.  Therefore, I wouldn't recommend them for highly active situations, but I'll take the comfort they offer in relatively low motion activities like riding the bus or walking.  Overall, considering my experience with other buds, these do a pretty good job but still have some classic earbud issues.

 
 
Durability: Overall I'd give these guys a good prognosis on longevity.  The flat-style cable is of a decent gauge and really only gets flimsy at the output of the inline volume control.  The termination at the driver is well coated with a silicon like substance which feels quite secure when I tug them out of my ears.  The driver enclosure is made of hard plastic and metal--at least I think metal, which goes to speak of the quality.  The TorqueValves are solid pieces and should survive the inevitable dropping.  The screw-in mechanism is tight nit and secure.  Overall I'd say the build quality and durability is quite noteworthy and maybe even outdoes itself a bit for this price tier.

 
 
Sound Quality: This is likely the part of the review you care the most about.  If you've read my past reviews, you'll know that I separate my subjective analysis of the sound into the three logical parts: the highs, mids, and lows.  Since this IEM offers 3 TorqueValves that all offer a unique sound, this section will be a little bit difference from my past reviews.  You'll see a highs/mids/lows section for each TorqueValve and a quick sentence or two summing up how it all ties together for that particular TorqueValve.  Keep in mind that these are subjective impressions that are all done with the double flange tips.  Also worth noting: since many users at this price tier will likely want to utilize these IEMs straight from a standard DAP, I will be driving them from a 160 GB iPod Classic and nothing more.  That fact is something you enthusiasts who read this should most definitely keep in mind.  I felt the iPod Classic is a nice "control" if you will.
 
REFERENCE VALVE (RED)
 
Highs: After listening to several tracks on other headphones and audio equipment and then switching to these, the first thought that immediately comes to mind with the Reference Valve in the highs is "controlled".  The extension is indeed lacking as a result, but the highs are certainly polite which can be a plus.  If my highs are not neutral, I would much rather have them err on the polite/controlled side than the shrill side--even if at the cost of some treble extension and energy.  Energetic highs almost always lead to listener's fatigue in my experience.  There is nothing razor sharp in accuracy or tone with the high frequencies... but let's be honest, how often do you really analyze the high notes all that closely?  If you answered "frequently", then this TorqueValve may not be for you.  For those of you who had an extra cup of coffee today and are listening to jams at 250+ beats per minute (yea we've all had those moments) this is not an ideal setup. On the contrary, there is nothing offensive about the highs and nothing that sounds particularly unnatural either. This leads to a decent experience when you're doing much calmer activities such as indoor household duties.  I might like a little more sparkle on my strings, but I know plenty of people who would not complain--or may even prefer-- what these offer in the high notes.  Symbols are reserved and echo dissipates quickly.  I'd say the highs match well with tracks that do not rely on a lot of musical information in the upper frequencies and with warmer tracks.  If you're going to pick a John to listen to, I recommend Mayer over Coltrane because of how this TorqueValve handles the highs
 
Mids: Okay, I might get a little picky here.  The mid ranges are a little dry.  They do not sound recessed in any way, just a bit dull.  That isn't to say everything isn't well articulated however.  Without the high frequencies getting in the way, the detail level in the upper mid range is actually pretty solid.  Layers of instrumentation and vocalists are easily separated.  Low mid ranges are not interrupted by the low frequencies and are also decently detailed.  I do not think the frequency curve as a whole is U shaped, but the mid range frequencies themselves might be a bit U shaped.  I can hear upper and lower midrange just a bit more clearly than the dead-center mids.  I generally prefer a little more mid-forward presentation and these are not that.  I'm also definitely pretty picky with my mid range.  I really recognize a place for these mids though.  I hate to toss the word neutral around, since it might be one of the most abused words on head-fi... the mids really do feel neutral in terms of stage positioning.  What I mean by this is that the mids are not recessed/take to the back stage, nor are they the center of attention and upfront.  My perception of dryness may be a result of my tendency to own mid-forward equipment and I think the aforementioned perception is a good indicator that the presence of the mids sits somewhere potentially more natural.  The mids are not dark by any standard that I am familiar with and they're certainly not forward.  If middle ground was Torque's aim with this TorqueValve, congrats.  It is achieved here, maybe at the cost of some lushness.  Lush mids have their own associated costs though... like loss of separation and potentially soundstage/details.  The imaging in this frequency range is well enough for an IEM and soundstaging is classic left/right IEM stereo (meaning I have nothing really to say about it either way).
 
Lows: The bass notes are also very controlled.  I'd even say they are recessed a bit, at least in the sub 100Hz region.  The junction of the mid range and the mid bass seems relatively linear to my ears, but at some point near the sub bass region there is most certainly a roll off.  It isn't a cliff by any means, but it is noticeable.  This might be an effort by Torque to preserve the lower mid range and to minimize the well-known bass bleed.  Don't read that as a recessed mid bass however.  I think the mid bass sounds pretty natural and not emphasized as heard quite often in IEMs and closed headphones.  Sub bass notes are much more tonal than impactful, and the lack of extension does make the bass sound like "one-note" bass at times.  I'm probably being too harsh here, but I do not think this TorqueValve reproduces bass levels that are neutral, at least at the sub bass level.  I do enjoy the mid bass control very much and its seamless yet distinct separation from the mid ranges.  Overall, not enough extension... but really dodged the "smeary low mids/mid bass" bullet.
 
Bottom Line: After going back and reading my notes, I realized I described a very clinical sound overall.  To me it sounds like I am complaining a bit about a clinical sound coming from an audio device dubbed as "Reference".  Reference should sound clinical to some degree, so maybe Torque hit the nail on the head with this TorqueValve.  I like natural sound with some mid forwardness and these are definitely not my TorqueValve of choice--but they most certainly have their place as a well rounder.  It is a decently flat sound with a noted lack of extension at both ends.  For the price tier, the sound this TorqueValve offers is adequate
 
DEEP VALVE (YELLOW)
 
Highs: The balance of the overall spectrum has shifted and this seems to give the effect that the highs have tamed even more.  Upon listening more closely, I have realized that this is not the case and that there are likely some psychoacoustics at play here.  Symbols have the same bite (or lack thereof) and the same polite nature is portrayed.  Since little to no effect is experienced when isolating the highs, I'll refer you to above, under the reference valve section, for my thoughts on the highs.
 
Mids: Unlike the highs, the mid ranges do take on a new form; they lose some grain and gain some cream.  The mids seems to have gained a semi-silky nature albeit are capped off with a bit of veil.  It makes the overall presentation darker and I think this is what initially made me think the highs were sounding different.  As a whole, the interaction of the highs with the mids is different.  The definition in the upper mids is less clear but somehow the added smoothness is very welcome.  I'd almost sacrifice a little upper midrange dexterity or the added smoothness here.  The mids lose that dry character I was describing earlier and despite the subtle veil really gain character.  The mids take a step back, and even though I said earlier I like forward mids I really like how they interact as a whole with this TorqueValve.  As expected, the low mids take in a little more life and the distinct separation found with the red valve between the bass and low mids takes a hit.  Everything in the low mids is bigger (and slower).  I want to emphasize that the difference in the mid range presentation is NOT subtle.  It truly sounds like a different IEM because of this change, even with the similar representation of the high notes.  The new mids almost make this IEM feel more comfortable, as silly as it sounds.  Not perfect by any means, but it reminded me of just how dry the mids in the red valve are.
 
Lows: The bass notes are a lot rounder than before.  This adds a lot of warmth to the overall character and sound presentation.  This is a complete 180 degree turn from the previous valve, which I described as having some bass extension/presentation issues.  The extra weight does well here and the "one-note" feeling is better managed here.  I hear a few more layers to the low notes and everything just sounds slicker down low--bass guitar and electronic bass.  Mid bass is ballooned a bit as expected and is less punchy and more rounded.  Again, this adds warmth to the overall tone which blends pretty well with the new creamy mid range.  This change is not as drastic as the midrange in overall tone, but once again the change is NOT subtle.  The character of the bass is different... better layered, better extended and just bigger (which isn't always a plus but a nice option).  I think it is important to note that it isn't a very tight bass, but rather a slick and warm bass.  This will still not meet bass-head standards, which is a plus in my personal book.
 
Bottom Line: I straight up like this valve better, and I don't generally favor bass.  I know this is supposed to be the bassy valve, but my ears really heard the biggest difference in the mid range.  The added cream (or maybe just the loss of the dryness?) really made this a pleasurable listening experience.  Very warm and weighty overall.  Songs requiring speedy and impactful bass should still be treated with something a little different perhaps, but just about everything else sounds fine!  The characteristics of the controlled highs with very subtle graininess is still retained, but it matches so much better with the other two spectrums in this TorqueValve.
 
CLEAR VALVE (BLACK)
 
Highs: Any grain that was in the highs is gone for the most part.  The highs gain some energy here but retain the soft qualities found in the other two TorqueValves.  I was honestly expecting a little more grain and potential harshness as a result, but even with some of the more symbol heavy tracks I tried I couldn't get this TorqueValve to misbehave.  Instead, symbols sound more crisp than before.  Surprisingly, the added dB in the high frequencies did not harm the previously capable separation between the upper mid ranges and the high frequencies.  This intersection is boosted but not smeared.  I give a big thumbs up to the added energy without any real acoustical costs to my ears.  Perceived clarity is up and grain is mostly gone.  I have nothing but positive things to say about what this TorqueValve delivers in the high frequencies
 
Mids: The previously mentioned veil and creaminess are gone now.  What has surfaced in the mid ranges in this TorqueValve is not as grainy as in the red valve however.  The mids sound a bit more reedy now and definitely more forward--which as you know by now is a plus in my book.  It complements the higher energy upper frequencies very well to add a lot of energy overall to the presentation.  Once again, there is nothing subtle about the changes in the midrange from the other two TorqueValves.  This is the only one of the three that brings the mids forward and makes detail retrieval undoubtedly easier.  Whether you consider this an actual increase in detail level is a topic up for debate on many threads in this forum, and that is where I will leave it.  Just know that the high frequencies are elevated and the midranges are brought front and center while the tone of each is cleaned up quite nicely when compared to the red valve.  Because of this, the clear valve is easily my favorite of the bunch.
 
Bass: So... you just read that the highs and mids are boosted, the lows must be left in the dust?  I'm not entirely sure how, but the I feel like there is more bass levels in this TorqueValve when compared to the reference (I'm beginning to see the usefulness of the reference valve).  There is nothing clinical about its presentation.  It is definitely a step backward in dB from the Deep Valve and it loses almost all of its roundedness.  The bass moves toward a more snappy timbre with layers when the music calls for it.  The bass is a lot tighter than in the previous two TorqueValves but still not any faster.  It loses a lot of warmth as a result.  Overall, the bass layers are existent and the separation from the low mids returns to capable levels.
 
Bottom Line: This is hands down my favorite TorqueValve of the bunch.  It brings a lot of life to the music and fills in a lot of what I thought was missing from the Reference Valve without overly coloring the timbre like the Deep Valve does.  The timbre is very natural to my ears all while sounding less clinical than the Reference Valve.  I know that valve has its place, but it isn't really for pleasure listening in my opinion.  The truth doesn't always have to be presented brutally and I think the Clear Valve gives a hint of character to the natural yet clinical sound that the Reference Valve presented.


 
In a Nutshell: I think at the price point Torque is shooting for (at least when I last talked with them over a month ago) is around the 200 mark.  There is certainly some stiff competition in this tier, but nothing at this level that I have heard of or experienced offers the flexibility of changing the sound easily this effectively and drastically.  The technology is implemented very cleverly and with very solid acoustic results.  You'd essentially be paying 200 dollars for 3 different headphones, and I know many of us are guilty of having multiple sets of IEMs/headphones to cater to all of our listening moods.  With the t103z, you get some pretty different characters to suit more than a few of your listening preferences and needs.  The fit is a bit unique as the bud needs to be inserted at a bit of an anteriorly pointed angle, but once it is in the right position the comfort is fine.  At 200 dollars for a case and three headphones essentially, you're getting a deal in my opinion.  No it is not a giant killer and yes it will have flaws in the sonic presentation but I think it is competent at the 200 dollar tier and offers a ton of flexibility.  I seriously recommend trying these out if you're constantly finding yourself reaching for a different headphone every time you sit down for a listening session, or if you're one of those people that travel and can never decide which headphone you want to leave the house with.  This is an acoustic toy for the indecisive and light packing audio enthusiast as an all-in-one solution.  The t103z is the swiss army knife for the casual audio enthusiast.  With more TorqueValves likely on the way at the time of the release of this headphone, the ability for the owner to expand their arsenal will only increase.  I hope to stay in touch with Torque Audio and review new TorqueValves and products as they arrive to keep this community updated.  I hope you found this review useful, and feel free to contact me with questions about the product and I will do my best to answer them for you.

 
As per standard, I will give a bit of a background to premise this review.  I do this before all of my reviews just to give the reader an idea of my experiences.  This allows the potential consumer to best judge my opinions and ultimately decide what kind of bearing my words have with them.  My reviews aim to express my thoughts with the main intention being to arm the reader with the knowledge to make the best purchasing decisions.  Knowledge is power, and I say power should go to the consumer in any market!
 
I come from a family of audio hobbyists/philes/enthusiasts/whatever.  Hi-fi has been part of my experience from the time of a child, and thus my standards for audio reproduction are naturally higher than that of your average individual or consumer.  I’m not making the “golden ears” argument, I am saying I have been around many different niches and types of hi-fi reproduction and my ears have received some training in the process.  My first exposure involved home fidelity, but I first started becoming adventurous in the car audio department when my teen years hit (naturally).  I found myself buying, selling, demoing, and modding consistently until I eventually completed a final project of building an entire audio system from the battery up.  I haven’t had to touch it for years, and probably won’t for a long time.  From car audio I moved back into the home theater/hifi scene and did some projects of my own, once again.  I have recently found my audio nirvana in the home, and don’t plan to touch that for awhile either after much testing/tweaking.  Naturally, my next move was the headphone world.  I’m currently diving into cans, learning as much as I can until I find my “heaven” in this realm too.  It is helpful reviews that help pave the way for those who want that ultimate experience, so I plan to contribute and pay back in the process.  I hope you find the following review of the KRK KNS-8400 helpful.
 
Comfort: The fit of these headphones is certainly above average to me.  It was one of the first things I noticed when swapping from other headphones of similar class like the Shure SRH-840, SRH-440, Sennheiser HD-25 I-II, HD280, HD380, HD448… even against higher tier models like the SRH-940, Beyer DT-770, Senn HD-650, CharterOak SP-1.  These headphones are comfortable overall because of the soft memory pad filled leather-esque pads utilized on both the headband and ear pads.  Even with this super padding, they are very light.  The clamping force is enough to be considered secure, but at the same time the soft pads do not apply much force around the ear.  I usually rate comfort on a secure fit to a loose pillow fit spectrum, and let the reader judge how “good” the comfort is based on what they prefer.  These fall in the middle of this spectrum somewhere; they have enough clamping force for you to move your head around without fear of slipping but do not have zero pressure at the ears.  I really find the balance fit to be quite nice, and certainly one of the nicer ergonomic designs around.  They won’t be as comfy to me as my SP-1 or HD-448, but they certainly will fit more securely which is almost a must for a portable.  I feel like whether you’re a pillow fit or secure fit person, these can’t let you down in the very least.  They’re just fine for multihour listening sessions and actually don’t warm your ears up a ton for being a closed back model.  Solid job, KRK.
 

 

 
Durability: Since I feel like these fit best in the portable niche, I’m force to elicit a higher standard.  The durability is fine.  They certainly won’t fall apart in your hands or crumble in your backpack, but they might have a weak point or two.  Anytime there is a swivel joint, a chance of weakness is introduced.  I’ve seen swivel models implemented in poor fashion and in nearly indestructible fashion.  These KRKs fall somewhere in the middle again.  The swivel joint in the headband that allow them to fold flat is pretty solid and protected in all direction.  The screw isn’t visibly exposed from any angle, which is a good thing.  It also doesn’t utilize a spring to snap back into place like I’ve seen before, which could be a good thing from a durability standpoint, as it is well known that springs can wear out.  The joints at the ear cups that allow the cups to tilt would be more prone to breaking that the aforementioned joints.  Honestly though, the only way I could see that happening is if there was a downward pressure pushing the cup further from its yielding point and causing it to snap (I could see this potentially happening at the bottom of a backpack, for instance).  The cable seems durable, yet still small enough for convenient portable use.  It is indeed detachable, although the locking design isn’t the slickest.  Once it is locked in I don’t think it is going anywhere as it utilizes a turn-to-lock system, AFTER being snapped into place (semi-forcefully too, I should add).  Could this mechanism wear out?  It wouldn’t particularly surprise me either way.  I’m probably splitting hairs in this section, but I think it is well to consider everything.  On the plus side, the headband is reinforced with lightweight metal and a plastic beam, and the pads are mounted really well on the headband.  It even seems as though this may be replaceable by unscrewing a panel and swapping.  I’ve certainly seen less durable portables, so I think these will hold up just fine through the battles of travel with just a little care and caution.  Don’t be stupid and they shouldn’t break.
 

 

 
Sound Quality: The comfort and durability may be the bread, but we all know it is what is in between that makes or breaks the sandwich – even if the bread is essential.  Just so you can get an idea just what kind of sandwich this is, I will break the sound up into the three logical categories of high, mids, and lows.  I will comment on each, likely referencing each within my comments to help you get an idea of how it all blends together.  I spend a lot of time before writing this section of the review, and it is always done separately from the rest of the review.  I listen to many tracks from many different genres and report my SUM experience here.  If you want an idea of the types of tracks I used, feel free to PM me or something and I can tell you some of my favorite evaluation tracks.  I will preface this section of the review by reminding you of my background in audio (see intro if you wish).  My honesty can come off a bit harsh sometimes, but I will attempt to help you understand my subjective experience to the best of my language abilities.
 
Highs: This certainly isn’t an emphasized aspect of the spectrum.  Cymbals in rock tracks that are notorious for getting out of control seem reasonably sustained.  The level of control in the highs is quite nice actually, and it is my guess that this control is what makes the sound of these headphones not so fatiguing.  Cymbals seem to have more of a “sss” sound rather than a “shhhapp” or “shhhh” sound, if that makes any sense or is helpful at all.  I guess the highs sound thin, in a sense… but not in a negative way necessarily.  While this does wonders for avoiding a fatiguing nature, it also means that high string notes are a little duller than I prefer.  Detail retrievable is a bit hindered in the highs because of this.  The sparkle that should be there on certain tracks can be a little laid back (for sparkle that resides in the highs, at least).  I will say that I do find the highs (8-10kHz and up) to be quite linear in sound, even if masked a little bit by their laid back nature… and maybe even a bit rolled off.  The roll off is actually a bit disappointing considering their potential as a monitor due to this linear presentation in the highs.  If someone came up to me and said “the highs are a little veiled in this headphone” I couldn’t really disagree with them.  I don’t think the highs are veiled in the sense that they are dark, I think they are veiled in the sense that they lack some sparkle and detail (not suggesting sparkle = detail).  Listening for details and separation is always more challenging in the highs anyways, so this potential handicap really doesn’t take away from the sound of these headphones too much… I just don’t think they are the best for doing tracking in the highs.  If that’s something you need, look elsewhere because these are not honest/revealing enough up top.
 
Mids: When compared to the highs you could say the mids are emphasized, but I certainly don’t think there are emphases within the mids themselves.  It is common to hear a midbass emphasis in a closed set of headphones just because of the inherent design of the sealed enclosure.  These do a good job at taming that potential by producing a pretty neutral midrange.  I know it seems like everyone and their mother is reporting this and that as “flat” recently, but I honestly think the mids here sound quite unemphasized and neutral.  From my experience neutral presentations are much more rare in the headphone world than in the loudspeaker world, and this makes sense because of the design.  Compared to the loudspeakers I’ve had the pleasure of spending decent time with that are neutral sounding, these KRKs do sound neutral to me in the midrange.  I don’t get a sense of “cold” or “warm”, and I don’t notice any part of the midrange shouting at me for attention.  This makes it easy for me to choose part of the midrange sound and focus on it, and even easier for switching from one instrument or sound to the other within the midrange to focus on.  To me, this is indicative of little to no emphasis on any particular section within the mids and therefore a subjectively perceived flat sound in the mids.  Notice my careful language here.  I find the highs a bit recessed, so I can’t say the overall sound is flat, but I can say the mids do sound neutral.  The flatter response certainly favors detail retrieval in this part of the spectrum when you’re looking for it.  I don’t find anything to jump out at me, but I do find it easy to find any part of the music in the midrange when needed.  This seems super useful for monitoring/tracking purposes.  The mids are true, and I really like that about this set.
 
Lows: Bass always suffers it seems like.  It is like the sauce, you better pick the right one to compliment the rest of the sandwich or it could ruin it all.  Getting a sauce right adds texture to the sandwich.  A dry sandwich is better than one with the wrong sauce, yet everyone generally sauces their sandwich because without it, it just isn’t the same.  A well liked, but conservative sauce was used here… something far from mustard or hot sauce and closer to something like mayo or bbq.  I have hardly any complaints about the bass.  My only real complaint is that is it unspectacular, which is kind of a cheap shot in itself.  The bass is really shed in a similar light as the mids are to me.  There is no midbass punch, no grumble, and no real low growl.  The bass lacks significant in-class emphasis.  Just like the highs though, I wish the extension was just a little better.  The bass is a pretty linear to my ears but once it gets to the 60Hz and below region it seems to start rolling off a bit.  Usually the trade off in bass is impact versus texture, and once again I find the KRKs to fall somewhere in the middle.  The impact isn’t bland, and the texture isn’t muddy.  I can hear tonal changes in the bass fairly coherently, and I hear some punch when the track calls for it.  The bass isn’t as fast as I’d like; the recovery could certainly be better.  That being said, I don’t think the speed in the bass is bad… just average.  A good fusion band like Chicago which utilizes electronic and string bass will show you what I am talking about.  The slick string bass responds pretty well, but isn’t as swift as it could be.  Usually bass that can keep up with strings like that lack some impact properties, so I guess that is just one extreme example of what I mean when I say bass texture. Overall, you put this sauce on my sandwich and I’ll rarely complain.  I won’t go home thinking it was the best sandwich I’ve had either.
 
Additional Notes: The isolation is just fine.  Nothing to ride home about but it won’t disappoint (I feel like this sentence has been the theme of this review).  It appears that parts like the pads, headpad, and cable are all replaceable and purchasable.  The headphones are easy to drive, although modestly enjoy even a simple amplifier like the FiiO e7.  It comes with a threaded 6.3mm jack that is removable to be a 3.5mm mini.  The headphones do fold flat, but do not come with a hardcase but rather a drawstring pouch for portable storage.  These also come with a removable inline volume control, which is cool if you’re listening out of a shared source and the other user isn’t using a volume you prefer, or for a fast kill switch.
 

 

 

 
Nutshell: These headphones lack a glaring weakness sonically and are ergonomically very friendly.  The asking price is quite reasonable (I got mine for 120, and it was going at that price in many places at the time of this review).  I think these headphones would be most useful for tracking/monitoring in the midranges.  In fact, these wouldn’t do horribly as a monitor at all considering their fairly neutral overall presentation and their especially neutral midrange.  For music listening purposes, I feel like these are a great well rounded set.  I don’t they will be spectacular in any specific genre, but I also don’t think they could disappoint either, and that versatility has to mean something.  This set is like a turkey melt; a safe go-to sandwich that is hard to mess up, guaranteed to taste fine no matter the time of day.  It almost seems like the perfect entry level headphone for a new comer to hi-fi, yet could be easily enjoyed by the audio veteran.  Kudos KRK, for a great value and well-rounded “plug and play” set!
 
 
 

It has started to become a trend that when I review equipment here on head-fi I give a small background regarding my audio experiences, in an effort to provide the reader of the material a better idea of my opinions to ultimately aid in objectifying such a subjective category of audio.  For those of you who have read my other reviews you may find this repetitive, but I still feel it is of importance to the quality of the review and for what the reader takes away from it.  So... here goes:
 
I am a young audio enthusiast who is relatively new to the headphone scene.  I may not have years of experience with headphones specifically as many of the other members of head-fi have had a chance to have, but I am certainly not new to the world of quality audio playback.  Audio fanatics run common in the family, so even from a very young age I have had a vast exposure to high end loudspeaker systems.  It is this exposure that I blame for my audio-snob like qualities today, as hearing music played back sloppily frustrates me to the point of frowning or even sometimes removing myself entirely from the situation.  Most of my experience comes with external setups, whether it be my exposure to family members' hi-fi loudspeaker systems or my own custom built extensive car set-up (soon to go all out on a home hi-fi system).  I am diving into the unrealized headphone niche of audio... being a college student and moving from place to place frequently has made headphones one of the most feasible options for enjoying beautiful sound for the time being.  I may be less than a year old in the headphone world, but I am certainly not new to audio in general.  I also think it worth noting that I listen to many different types of music for these reviews, and although I usually don't mention the song genres specifically, I think it should be known that I listen to as many genres as possible for these reviews, whether I find such a genre enjoyable or not.  Regardless of whether the genre is of my taste, I try to pick out the strengths and weaknesses the headphone offers up for said genre and write based on the sum of all strengths and weaknesses.  My best realized sonic experience comes from the Sydney Orchestra playing in the main hall of the Sydney Opera House.  With that disclaimer said, I will do my best to draw comparisons from other headphones I have heard as well as make comparisons to external setups for perspective's sake.  I hope you find this read informative, and do not hesitate to ask me specific questions if this review did not answer your question.
 

 
Comfort: Compared to other headphones I have owned and demoed, I have to say these are probably a notch below average unfortunately.  While I have not tried the SRH-840 for more than a couple minutes, I can safely assume that these are probably more comfortable overall, but certainly still have some issues.  The clamping force and overall comfort on the ears is just fine.  My complaint comes both from the weight of the headphone and from the pressure of the headband.  Shure makes quality products, but on their Studio Reference Headphone line it just seems they have struggled in the headband department, as many complaints regarding this physical piece of the headphone are out there for the SRH-840 as well.  I find that they are much less comfortable than both my Sennheiser HD448 and CharterOak SP-1 because of the pressure the headband applies on the top of the head.  It takes frequent adjustments after as little as a half-hour listening session.  On the upside, the velour pads are very comfy and protect against sweaty ears for multi-hour listening sessions, unlike my SP-1 or HD448, despite being closed and offering some isolation (more on this later).  Unfortunately I have to report that the comfort on these headphones could be much better.
 

 
Durability: Don't let the plastic material choice cause you to draw erroneous assumptions about the build quality of these headphones.  They might be on the heavy side, but they're certainly built like a tank.  To actually break these things would take some effort, and the hard case that comes with them renders them likely candidate to physically last as long as you want them to.  As mentioned earlier, they may not be the most comfortable, but they make up for it in durability.  The swivel joints on the Shure aren't even exposed.  I really think the only way to damage these without smashing them against something would be to twist the joint the wrong way with some hearty effort.  An extra set of pads are even included in case you ruin your current set.  Absolutely no worries here.
 

 

 
 
Sound Quality: Since this is arguably the most important aspect of the review, I will spend the most time on this section and break it up into the logical three categories - Highs, mids, lows.
Highs: Airy, detailed, extended and controlled.  Wow, what a combination!  For my experience at least, it seems that when the upper registers have the lightweight feel to be as nimble and detailed as I am looking for, I have to pay for it by tolerating a brighter feel.  I am okay with a subtle brightness if it does indeed provide the detail in the upper mids and highs, and it usually has to roll off a tad early just so it doesn't provide too much listener's fatigue.  These SRH-940s do an incredible job of keeping the highs airy and detailed while never becoming bright.  The control of the highs is even more impressive when you hear the upper register extension these have to offer.  I haven't quite heard extension like this in a headphone... in fact these SRH-940s maintain high frequencies like many of the loudspeaker setups I have heard do, which is quite impressive considering the external setups I am speaking of have a dedicated driver for the highs.  The extension reminds me a lot of some dedicated MB Quart car tweets I have, but the Shure's don't require the rest of the frequency to have ton of juice to keep up.  Even more so, the highs remind me of an external setup in the sense that it seems they have a volume sweet spot.  Since external setups often have dedicated drivers for specific frequency ranges, it is not uncommon to hear the balance of the setup change slightly as you increase or decrease the input power.  Often each set of drivers will have slightly different sensitivities to the input power and thus turning the volume knob can generate changes in balance.  Usually there is a volume sweet spot for which the system in tuned for.  I notice these balance changes as I up the volume outputted from my FiiO e7/e9 combo, and that these headphones have a sweet spot.  The presence of the highs seems to become extreme passed this sweet spot and there seems to be a slight emphasis on the mids below said sweet spot.  This, of course, is somewhat subtle but still worth noting as I don't observe these balance changes as drastically in my other headphones.  This intrigues me since the headphone only uses one driver per ear cup, and is most likely indicative of an impressive soundstage.
 
Mids: Always my favorite part of the spectrum... if it can't do midranges it isn't for me.  In my opinion the mids are very neutral in this Shure.  It seems as their purpose is just to tie the highs and lows together, and this gives it a very natural feel.  The vocal ranges certainly aren't as juicy as they are in my CharterOak SP-1 but are far from veiled or colored.  Just like the highs, this range is very well controlled and imaging is superb for a headphone, especially a closed one.  The upper mids definitely contain more detail than that of the lower mids, and overall I find the detail in the midranges to be ever so slightly behind the SP-1.  The imaging however in the Shure is quite impressive, giving you more a "room" (wide) feel than the "hall" (direct) feel the SP-1 does.  The SP-1 puts you a little closer to the music and the Shure makes you take a step back.  The SP-1 presents the music more athletically while the 940 gives it more of a laid back feel, while both sounds still remain "analytical".  I also find my SP-1 to be very mid-forward, so that may have something to do with it.  Honestly, because of the nimbleness, increased detail, and clinical feel in the midranges from the SP-1 I would probably dub it a better "reference" studio monitor than the SRH-940 (SP-1 was also more money), but I'm finding I prefer the Shure when I just want to listen to the music and not think about it.  When extension is the most impressive aspect of this headphone, it shouldn't be surprising that the mids have less to comment about.  That being said, I have no real substantial complaints about the midrange - they are very natural and "fair".  If anything they swim in the large sonic space the SRH-940 offers without feeling empty or gapped, and give one more bullet point of evidence towards the above average soundstage.
 
Lows: This could be the most difficult aspect of the headphone to asses for a couple of reasons.  It doesn't help that I am very picky with my bass, and I feel that it is the first to go as you work your way into cheap options.  Bass presence usually is never the problem, but bass quality almost always is.  It seems so common that bass is overdone and spills into the mids, drowning it out.  I prefer bass that carries some impact, but more importantly carries tone and recovers promptly.  The first thing I notice when equipment is underpowered... whether it be headphones, car components, or speaker towers is the bass becoming sluggish and lagging behind.  Obviously amplification makes huge differences throughout the spectrum, but in the bass is where I generally hear the most substantial difference.  I noticed the same with the SRH-940s.  Straight out of an iPod classic I noticed that the mids and highs were hardly affected, but the lows lost a lot of texture and layering, most likely due to bass notes not recovering fast enough and leaking into each other...leading to more drug out than separated notes.  These sound fine unamped, but MAN if you throw some real juice behind them the bass just tightens up and becomes layered, fast, deep, and noticeably impactful at least.  The low end extension of these headphones is nearly as impressive as the extension in the highs, effortlessly hitting very low notes with more volume than other headphones I have tried or owned.  The bass reminds me a lot of the bass in the Senn PX-360 but with WAY more control to it and no bleeding into the lower mids.  In fact, if anything they have a slight recession in the low mids/midbass region which help with this bleeding effect.  Do I prefer this recession?  Not entirely, as I feel my SP-1 seems to love this range while still preventing the "bass bleeding" into the mids.  The Shure certainly makes a nice sonic compliment to the SP-1 for this reason.  This ever so slight recession in the mid bass is probably my only true complaint of the Shure SRH-940 with regard to sonic signature.  All the rest of my mentioning was more comparison and appreciation of difference rather than dislike.  I will conclude this section by saying the bass extension, layering, and texture are all very excellent while the bass impact is fine and the recession in the midbass region is mildly frown-worthy.
 
Additional Notes: The "extras" that come with this headphone are excellent.  Shure includes a nice hard zipper case that should protect them quite well if you are a frequent traveler.  Inside the case are an extra set of velour pads (which are removed from the headphone very easily, yet still remain secure during use), a removable straight AND coiling cable (very nice of you Shure), and room for a portable player/amp if you want.. my iPod and e7 fit just fine.
Isolation is fine/average - better than my loose fit SP-1 and slightly worse than my HD448... I'm guessing due to the velour pads.  I will say that for how big of stage and the imaging they provide.. it is impressive these offer the level of isolation that they do.
I will say that it is subtle but nice that they quantified the notches on the side of the headband so you can get the extension of both sides of the headband right the first time to allow quick fitting.   If I let other people use the headphone and they adjust the band I can remember "if I set both sides at setting 3 that it will be comfortable" and that is nice.
Both cables come 3.5mm terminated with the ability to utilize the threaded 6.3mm adapter.  Both cables attach into the left ear cup via a twisting lock.
 

 

Nutshell: Most definitely a treble lover's headphone.  It does well with instrumental and string oriented music.  They sound fine unamped, yet utilize an amp very well.  This means that if you're looking for a headphone that will run out of a portable device or anything unamped and know you may upgrade to a better amplifier later, these are safe bet.  Just remember that these (to my ears) seem to have a volume sweet spot and you may have to do some tinkering to find that once you amp them.  For 300 dollars, I would say you're getting what you paid for.   The sonic signature is gorgeous and really the only hiccup is the slight midbass recession... but the control and extension in the highs and lows combined with the large soundstage and solid imaging make this headphone easily worth 300 dollars.  Value wise, I think it would be tough to say these are anything other than "solid", especially considering all the goodies you get with them.
 

 

Usually before writing a review, I give a little background to give the reader an idea of my perspective and experience so the evaluator can best utilize the information provided.  I also start out with a small disclaimer, saying that any analysis regarding sound is of subjective nature, and other ears may disagree with my findings.  Despite the subject nature, I try and provide a fair analysis with objective notes.  I am also open to respectful criticism and responses as well.  Enjoy!
 
My entrance to the audio world began as a child.  My family is scattered with audio enthusiasts, so it is only natural that I was exposed to hi-fi at a young age.  This early exposure has forever ruined my tolerance for the abundance of subpar audio equipment that other non audio loving people may find themselves enjoying.  Now a college student, I find myself having to remove myself from the room when someone decides to play music through their laptop speakers, or are satisfied with the stock speakers while watching a movie on their television.  It is not in disgust that I leave... the shrill noises honestly make me uneasy and can give me a headache.  Call me a snob, but I blame the folks   My teenage years brought along a niche for car audio, and I wound up educating myself, talking to others, joining forums, and eventually moving into DIY projects and eventually constructed a fairly extensive system as a final project.  I won't be touching it for awhile.  I know it's easy to think "Kid with a knack for car audio, must be one of those who likes giant muddy lows, shrill highs, and has no care for the mids".  I'll inform you that's far from the case - I built the car system with a home audio spirit in mind.  Anyways, maybe that'll serve enough for the background.... on to what you came here for - The Sennheiser PX 360.
 

 
Comfort: I have some mixed feelings with the comfort here, but that being said... they certainly aren't uncomfortable.  The headband is padded quite effectively, and are very lightweight on the head.  The only real concern about comfort here is their firm fit on the head.  Some may find the fit too firm, while others may describe it as secure.  I am somewhere in between, acknowledging both.  I appreciate the firm fit for traveling purposes, because if I decide to lean my head back against a headrest it won't push the cups around on my ear... but a firm fit certainly loses that pillow-like feel that is ideal for multi-hour listening sessions.  I will say the adjustment settings will fit anyone, from pinhead to giant dome.  I will also mention that the ear cups are the smallest on a set of circumaural headphones that I have seen.  I have average sized ears and they just fit - it takes a little bit of strategy to fit my ears inside the cups, but once I do the comfort is fine.  I find the comfort of these headphones difficult to judge, so I will have to rate it as "mediocre".
 

 

 
Durability: The build quality of these headphones is solid.  Don't let the lightweight nature of these headphones fool you, these guys are meant to withstand some hours at the bottom of a full bag.  The headband is reinforced with metal and wrapped in a nice pleather material - etched with a slick "Sennheiser" branding on top.  The rest of this headphone is plastic, but not the cheapo kind.  The cups are made of a very sturdy plastic, and the joints are a hybrid of plastic and metal hinges.  Quite honestly, either something intentional or unusual would have to happen to break these headphones.  Really the only point of weakness is the puny cable, which I am sure was in an effort to maximize portability.  While the cable is ultra thin, it isn't like the termination at the cup is going to get stripped out without some effort.  They're solid while remaining lightweight... the end. 
 

 

 
Sound Quality: Arguably the most important aspect of the review, I will break it up into the logical three sections - the highs, mids, and lows and talk about each.  I'll preface by reminding you of my background, and also letting you know that I can be somewhat harsh at times with what I expect.  At the same time, I will keep things in perspective (like price) and attempt to give an objective-esque analysis while still acknowledging the subjective nature of sound perception.
 
The Highs: My initial impressions of the highs were not good, but this may have been due to break in (or psychological "getting used to"...whatever you may or may not believe in) or just the semi-strange nature of them.  The presence of the highs are definitely more substantial than in other Sennheiser models I have heard (HD 428, 438, 448, 595, 280, 380, 238, 228).  The symbols are still controlled in all types of music, yet the highs seem to have a very particular emphasis in a specific frequency range.  This emphasis lies in the low-highs or high-mids...more so in the vocal ranges than anything else.  This gives these headphones a bright type of feel.  While I do not necessarily mind a bright sound, I do have a problem with it if it does not offer up the upper ranged detail many bright setups do.  I'm okay with bright IF the brightness is subtle and it carries a fat vocal range, lots of detail, and has a nimble sound to it (much like my SP-1).  The detail in the highs of the PX 360 is mediocre at best, and the vocal sweet spot on these headphones is extremely narrow and this causes an effect that is twofold in my opinion.  Firstly, the treble ranges are much more alive and exciting, maybe too exciting in a very specific range.  This emphasized sub-highhat treble can really be for the better in certain tracks, especially those that target giant perceptions in the dynamic ranges of vocals to reach "piercing" levels with purpose... but for those tracks that target a more laid back vocal range the PX 360 tend to try and give it extra life which may hinder the overall effect of the relaxed sound.  I would also say the transitions within the highs are almost a little sluggish and certainly not as smooth as I am used to.... maybe even a tad choppy.  The spacial resolution of the highs are just fine despite the aforementioned oddly specific emphasis.  With female vocals, I find a very bimodal effect with this emphasis.  Certain female vocalists are extremely controlled while still retaining body and life, and certainly unstranded and not overly lightweight and airy.  Other times, I find certain female vocal ranges to be way overdone, almost harsh sounding, and uncontrolled.  It really just depends on whether or not her voice falls within that strange vocal "bump" in the sound Sennheiser packed into the PX 360.
 
The Mids: Speaking of vocals, when the lyrics start diving down into the mids they clean up real nicely.  They suddenly smooth out and remain true to the intention of the artist, whether that be alive or more relaxed.  The space in the middle ranges is also much larger, adding more space to the music despite being a (very) closed setup.  The midranges are a little colder than I prefer, and maybe just a little too empty.  The mids are usually the strongest aspect of a Sennheiser headphone (with my experience) and I must say these do not live up to the rich Sennheiser midrange I am accustomed to.  Regardless, I wouldn't say the mids are bad.  The detail exists in the wider space of the midrange, and everything sounds a bit more uncolored.  Unfortunately, I feel the mids to be a bit recessed, and that is the opposite of what I prefer.  Some argue an emphasis on the mids slows the music down a bit and that emphasizing the lows and highs makes for a more exciting sound.  I would have to agree with them, but with that same breath mention that present midranges make the music more enveloping, natural, and real.  Whether these midranges be rich and silky smooth or lean and accurate, their presence is an important aspect to quality sound... and I'm afraid that the PX 360's mids do not have enough life for me despite some of the positives within this frequency range I recognize.
 
The Lows:  Just when you thought I was hating on this headphone, I come bursting in with some good news: the lows in this headphone are superb.  These have the richest low end of the Sennheisers I have heard, and have a more preferable low end response to me than the beloved ATH-M50, Ultrasone HFI-580, 680, and 780 (from the limited experience I have had with these headphones).  The lows are definitely emphasized here, and while I am usually against it, it adds a great foundation to the music in this case.  The semi-hollow mids and overdone highs are at least complimented with solid low end.  Ideally I could take the low end in these headphones and give them to my HD 448 - that would make a real nice sound.  As always, the lows aren't perfect by any means.  Without amplification I find the bass a little bloated and "loose", but I really realized the potential of these drivers once I amped them with first the e7 (decent results) and furthermore the e9 (good results!).  Even with the e7 the bass recovered much faster, packing a punch and then withdrawing when needed.  The bass is much different than my HD 448 in that the response is not very tonal, but alive and punchy.  It makes for a good partner to any type of music that is proud of its lower frequencies.  Additionally, the PX 360's lows are very sensitive to a bass boost function or EQ adjustments meaning you can play around with the lows a lot and tune them to how you like.  These might fringe on the edge with bassheads as far as having enough impact, but I wouldn't be surprised if you could juice them enough to get there without sacrificing the rest of the spectrum this headphone offers.  I will say the robust bass as opposed to tonal bass means it is bulkier in both volume and speed... just something to keep in mind... the lows are not nimble.
 
Additional Notes: The isolation on this set is quite impressive for a passive system.  They have little to no leakage and do a great job of keeping unwanted noises out.  I really feel like these headphones are built for the frequent traveler, and more specifically the frequent flier.  The bag they fold up into is a soft case and stows away while taking up minimal space - really nice for packing around on a bus, train, plane, or even just to the library.
 

 
These headphones are easy to drive like their ohm rating suggests.  I say this because my experience with other 32 ohm headphones (DT770, HD448) have suggested differently. The PX 360 barely benefited except in the lows a bit (tightened up) when moving from DAP to e7 to e9.  If you're looking for a solid portable set without having to drop more cash on an amp, these sound close to their potential without an amp.
 
These terminate on the RIGHT earcup.
 
The small L-plug makes for a nice termination in regards to space.
 
Nutshell: While these have some strange sonic characters, outside of the sonics they have a lot to offer as far as functionality is concerned.  These are great for flying, especially since they take up very little space when traveling and isolate quite well.  They may not sound as silky smooth as some other sets, but they certainly have the impact and lively type sound.... so the question is this: are you looking for a smooth, rich, natural sounding set or a punchy, alive and exciting set?  Don't let my tastes turn you away if the robust lows and accentuated highs are what you're looking for, these have it, no amp necessary.

As a young audio enthusiast with most of my knowledge base centering around car audio, I found my appreciation for sound begin translate across into the home.  Audio nuts run in the family, so between knowledge obtained from relatives and my own satisfaction of curiosity, I have come to learn much about the extremely complex niche of home loudspeakers.  Being a college student makes living situations far from ideal to venture (as a consumer) into the large, lovely loudspeaker market.  Naturally, the right avenue to achieve beautiful sound seemed to be headphone Ave.  While not related to the product I am reviewing, I feel as though to really deliver accurate information to the reader - and essentially give you, the reader, what you're looking for - I should give you a background to better understand my role in the sound community.  With this understanding, it will be easier for you to judge the accuracy of my writing and the validity pertaining to your needs or wants.  I hope to deliver useful, indicative information to you - not to necessarily persuade a purchase.
 
With all the background aside, let's focus on these phones.  These Sennheiser HD 448s are a closed circumaural headphone, with an impedance hanging around 32 Ohms , SPL ~114dB and a frequency response from 16 -24000Hz. 
 

 
Comfort:  Technicals aside, these are a super comfortable phone. The earcup is large enough to indeed be circumaural, although those with over-sized ears may find this a tight fit.  These aren't the smallest cups I've seen on a circumaural headphone, but they're smaller than the pictures show initially.  The photo below (even though a bit is cut off) shows the cups to be around 3.5 inches on the outside but only about 2.5 for the ear itself.  My ears are of average size, and I have no problem fitting into them for a seal.  Pads are mildly stiff to create a seal, but the pressure on the head is barely noticeable. The headband rests nicely with an additional pad included to reduce pressure.  It is easy to forget these cans are on your head.  This is barely worth mentioning, but hours of listening does lead to a pair of warm ears.  With headphones that have any isolation at all, this is to be expected.   The comfort and weight give a distinct advantage for traveling.  The included bag is pretty standard (black, cloth, subtle Senn logo with drawstrings) but is nice for packing around a portable device in addition to the phones.  All in all, these give a comfortable, semi-loose fit on head - isolating quite well despite the low clamping force.  I will say if you prefer a secure, tighter fit as opposed to a more loose pillow like fit you may find these to not be as secure.
 

 

 

 

Durability:  This is where the 448s are probably the weakest.  To be honest though, anything that isn't fragile can be taken care of with just a little conscious effort.  For a 100 dollar headphone, they're about what you would expect - adjustable plastic headband and exterior with above average padding, and a small cable (diameter) w/permanent one sided connectivity.  I do like the jointing system included here for limited swiveling and rotation, but improper care might render these plastic joints a weak point.  Bottom line: I think with some care these should be durable enough.  I've had them for over a year now with no issues and have taken them on numerous trips.. planes, trains, automobiles.
 

 

 
 
Sound Quality:  I'm quite picky when it comes to sound, so I may tend to err of the harsher side (although not always).  I will do my best to offer a perspective here with my experienced ears outside of headphones.  When I started my consumer research with the goal of obtaining my first set of solid headphones without destroying my wallet, I ran through some options hovering in the $150 range.  While I found some nice options, I absolutely made the right choice by backing off price-wise to obtain these HD448 (ehm, ATH-M50 - greatly prefer the 448).
 
     I'll start with the highs:  I'd say for ~$100 you're getting more than what you paid for.  Symbols are present, yet not harsh.  Higher frequency female vocals sound controlled and accurate with no distortion.  The presence of the highs is significant enough in that you won't need to seek them out, but do lack the excitement to raise the hair on the back of your neck.  I would describe the highs as natural, and very relaxing.  Some may accuse the highs to be a bit boring, and if they did I wouldn't be able to tell them they're wrong.  I do thoroughly enjoy the emphasis on how organic the highs are in these cans however, almost like a sense of refreshment.  While the highs lack the excitement you might find in a Grado, I promise these headphones won't generate the listener's fatigue you'll find in brighter setups.  In fact, even against much nicer headphones, I could argue that these are one of the least fatiguing in sound signature.  The overall dark presentation could be considered favorable for long plane rides.  The highs are well controlled here, without hiding too much.
 
     The Mids:  I tend to enjoy this part of the spectrum more than the high or lows, and I feel a good mid-frequency is what separates the nice from the poor.  Mids are absolutely underrated in the untrained ear.  That being said, mids add an unrealized dimension to those who have been listening to less than ideal sonics.  The mid-range frequencies produced in these are absolutely unmatched for headphones I've heard in this price range.  The mids alone in the 448s make a Bose price tag look like even more of a joke than it already is.  The vocals are wonderful, and way beyond what I expected for this tier of can.  Guitar string recoil is refined and separation from the vocals is definitive.  Piano mid-notes are true.  The foundation of the sound can tangibly be associated in this range of the spectrum. The quality mids add a body to the music that compliments the neutral highs quite nicely, avoiding an airy, empty sound which strands the highs as sound lacking mid-range does.  These cans avoid the mudding together of mid-notes, which is more common than it should be for a lot of audio equipment.  The aforementioned makes these headphones ideal for vocal and acoustic based sound.  Sennheiser outdid themselves with the mids here in this price range - I was impressed.
 
The Lows:  Overall, I would have to say quite disappointing at first, and still lacking a bit.  Running these 3.5mm and no amplification really causes the 448s to draw a blank here.  They lack the enjoyable thump in fast paced rock and certainly don't have the balls for any hip-hop oriented music.  These seem to have trouble with a specific mid-bass note, it almost comes out "fuzzy" at times.  This could be my picky ear speaking, but after logging hours on another (more expensive) headphone I really notice it.  However, this isn't to say they can't hit the lows.  These Senns reproduce them quite accurately in fact, just in a muted fashion.  Mid-bass percussion and bass guitar strumming sound articulate, just muted.  This is where a better sound source or amp can drastically improve these cans.  I ended up amping them (FiiO e7), and while I did notice a mild positive difference in the highs and mids, the assistance in the lows introduced a substantial improvement.  I was able to get some thump out of them with some bass-boost assist on the amplifier (low setting on FiiO e7).  Generally, I try and steer clear of bass boost, given that I am far from a basshead and it usually just skews the spectrum - but here it really was necessary.  To be honest, I found these headphones a surprisingly difficult 32 ohms to drive.  I know impedance isn't tell-all when talking about ease of drive, and the HD 448 are an example of that.  They sound just fine unamped, but amping them helped quite a bit - even more so than amping a set of 32 ohm Beyerdynamic DT 770 in my opinion.... surprising, right?  I guess the take home message here is this: don't expect much of anything from the lows (below mid-bass) unless you're listening for it, but know you can improve these later on with amplification if you're tight on money at the moment.
 
Additional Notes:  Just like any headphone worth owning, it will require some burn in time.  Out of the box these sound quite harsh with noticeable crackling.  I recommend at least 30 hours of burn-in, and wouldn't be surprised if more was needed.  Don't be fooled by their sound out of the box!
 
Also, these isolate quite well as a closed can - making these even more ideal for traveling.  They have no problem reducing background chatter, but do not completely block outside noise (not active noise canceling).  They leak very subtly despite sounding quite loud off the head.
 
As with most closed cans, imaging is inferior.  The sound quality is great, but the soundstage is limited by the closed back design of the headphone.  That being said, it isn't all that narrow... just not as favorable as some of the open models I've experienced.
 
I would also consider these cans aesthetically pleasing, if this is of significance of you.
 
 
In a Nutshell: these cans are a steal for the money.  I had no hesitation giving these 5 stars in the value department.  I am happy I went with these over some more expensive models I was initially eying.  Highs are fine, mids are glorious and lows are disappointing (unamped).  A ton of sound for 100 bucks, and operate fairly well right off a portable device.  These still represent one of the best "values" I know of.  I find myself recommending them to many people who are on a tight budget and appreciate a natural response that isn't necessarily bass dominant.  If you don't plan on amping these right away, I suggest you do so in the future.  Most headphones of higher quality than these will require amplification anyways - these flirt with the line of amplifier necessity.
 
If you have any questions about the Sennheiser HD448s, reply with a post and I would be glad to answer!