I was initially hesitant to purchase the Beyerdynamic T90 given their frankly misreported reputation as bright and peaky, but taking a little bit of inherent risk paid off a large dividend in the end. As I was planning on buying a pair of headphones as a reference set for my upcoming review site, I was initially drawn to the Sennheiser HD 800 and Beyerdynamic T1. To acquire either, I would have been required to sell off my desktop computer to obtain the necessary funds for purchase. However, I noticed the price on the T90 had dropped by half of what I had seen over two years ago when I was considering purchasing the T90 refurbished for $399 from ProAudioStar. Back at that time, I backpedaled on that deal later on when I saw the HD 700 drop to around $450 on SonicElectronix and, as it turned out, the HD 700 was far too dark in the upper midrange and in the uppermost treble for my tastes.
Fast forward to about a month ago, I noted in passing that the T90 had dropped considerably in price, going for around $200 or less used and around $229 to $299 new with the introduction of the
Chrome Exclusive Limited Edition model. I was completely--and ignorantly, as I would later find--content with my DT 880 Premium 600-ohm but I decided to bump up the plan of getting a serious set of headphones for my review site to now. The reason being was by a stroke of luck, an observant Head-Fi'er noted my otherwise stray dangling post in a For Sale/For Trade listing where I indicated there I had acquired the DT 880 from the seller, and expressed his interest in buying them from me. After accepting his offer and selling off the pair to this individual, I had sufficient funding for a pair of headphones in the $200 to $300 price range. I was faced with two decisions: (1) sell off my desktop and buy either the Sennheiser HD 800 or Beyerdynamic T1; or retain it and (2) buy the T90 blind and see how that would fare, for better or for worse.
Quickly, I read, read, and re-read reviews and I found quite a few reviewers raving about it online and then the few who said it was a bright, piercing experience and was best avoided. What stood out to me were the comments on its excellence in demonstrating excitement, presenting realistic soundstaging and the high level of detail retrieval. Realizing that the positive comments seemed to be far more persuasive and also noting that I had enjoyed the DT 990 Premium 600-ohm, I reasoned I would never truly know what these headphones sound like unless I acquired them to try them first-hand. After all the complaints and trashing of this headphone even by a couple prominent members of Head-Fi, I am so glad that I took the risk and bit the bullet!
I have been missing out on so much and if I could describe these headphones as the product of two other headphones, I would say these take the excitement and fun factor in the Denon AH-D5000 minus the minor annoyance of its very slight lower bass boost and combine that with the extreme detailing and refinement of the HD 800. One thing I recall the HD 800 being very proficient at–and previously the only headphone that I thought could do this–was allow me to clearly and immediately see the individual sounds in recordings as their distinct separately recorded parts. This is analogous to an overhead projector (or recording) and being able to make out each of the individual transparencies (or tracks) on top of one another as they are being placed, removed and adjusted (or panned in and out, having equalization applied, and so on) as the presenter (or recording engineer) sees fit.
With the T90, I was instantly reminded of this quality in the HD 800 when I had demoed it and I also get this same mixing room-level access to real-time transparency-like detail-mongering of all my music. Only unlike the HD 800 which came across as a tad reserved and contemplative at times, T90 is extremely dynamic and fun-filled as if I had become the microphone there on the day of the recording with all the soul and fervor of the player or singer performing right there in front of me still intact.
Listening at 85 dB, the film industry's calibrated reference level which is predominately used in the music industry as well, the T90 sounds like heavenly perfection. As such, listening at lower volumes of 70-75 dB, my standard listening zone, the T90's definition and finesse does not diminish.
On a side note, I am also quite surprised at how the midrange is no longer ever-so-slightly recessed like it was on the DT 990 Premium 600-ohm and, to a lesser degree, on the Denon AH-D5000. I was also afraid given all the complaints about the highs and treble in general and the reported U-shaped nature of these headphones that the midrange would be restrained to some degree dynamically. I have found there are dynamics in the entire sound and this translates to every portion of the frequency range, including the midrange. When I listen to older recordings including some from the big band genre, the midrange is very expressive and detailed unlike on the Denons or the DT 990 Premium 600-ohm which have a tendency of making the midrange seem slightly distant and reserved at times. Additionally, several tracks that I use specifically to test for brightness and that I know for a fact had minor treble issues on the DT 990 Premium are actually, by virtue of the T90's improved drivers, smoother, more dynamic and far better extended.
Much to my satisfaction after testing around a dozen or so devices, I will say these headphones can be bright but
only if you pair them with an underpowered or bright distortion-ridden source. If I plug them into a Lightning to 3.5 mm Headphone Jack Adapter connected to my iPhone SE, its highs can be piercing with a few modern brightly produced music but only due to the fact that the bass is quite underpowered and underrepresented, thereby pushing the treble and midrange forward. If I plug them into my iPhone SE's built-in 3.5mm headphone jack, they are a teeny bit bright but the lower midrange and bass has filled in by a very noticeable amount and I am never bothered. However, if I plug them into my Surface Pro 4 or–to a very slightly higher degree of improvement–into, say, a LH Labs Geek Out V2 or an Objective2/ODAC combo (which was bright with my DT 990 but not the T90), the T90 achieves an otherworldly level of clarity and naturalness without any brashness or brightness to speak of.
These conclusions come after having carefully demoed many headphones including several flagship or top-of-the-line models, such as:
HiFiMAN HE-1000: possesses great frequency extension but is reserved dynamically even with the most powerful of desktop amplifiers/DACs
AKG K812: has a weird resonance combined with an inconsistent, peaky treble response
Sennheiser HD 800: possesses incredible soundstaging and pinpoint detailing, yet lacks ever so slightly in engagement though nothing like the HE-1000
JPS Lab Abyss: has great lower midrange and bass along with a very strange lower treble and upper midrange hole that reminded me of the HE-400 (original release; not S or i)
Grado PS-1000: has a soft distortion which clouds the inner detail, and its upper bass and low to middle treble are noticeably boosted in an effort to remedy this only making them sound even more off
In short, unless I ever get the chance to demo the T1 and it can prove compelling enough over my T90 without being too analytical, I can safely say the T90 is my official end-game pair of headphones. For the measly sum of $200 which I paid for them, I almost feel like I did something morally wrong because their current going price on the open market has to be the greatest steal in Hi-Fi to date! I am extremely proud and quite enthusiastic to be the newest member of team T90!