While I said it would be a few days, I think I got a good feel of these...so here is a full review:
Pros: Bass, clarity, transparency, imaging, comfort,
Cons: Treble, build quality for the price, price
Introduction
I should start off by describing myself, experiences, among other things. The term "audiophile basshead" fits me well. I like bass, but also appreciate great sound quality. Give me bass and a good soundstage and I will be a happy camper. With that being said, I tend to look for open headphones that have good bass...which this definitely fits. I have only had/tried three other headphones. Those being M-Audio Q40s, Numark Electrowaves, and Beyerdynamic DT990 pros. The Q40s where my first "real" headphones other than gaming headsets that I have used for music and gaming. They were quite nice, but died within months, which lead to the Numark Electrowaves which were a replacement to the Q40s as InMusic (the parent company) didn't have any replacements for the Q40s. The Electrowaves were the same thing as the Q40s basically, except for more quality oriented which leads me to wanting quality over quantity...thus leading me to the DT990s. I had the DT990s in February ´15, but returned them within a month as they couldn't handle much bass. They did have quite a bit of bass...but a boost was out of the question which limited the bass I could get form them. After months of researching, this leads me to today and to the T90s.
Burn-in so far: about 10 hours.
Equipment: FiiO E6 + Behringer UCA222 cheap, but will edit once I get a better amp or amp/DAC.
Ergonomics
These are basically the same as the DT line, except with a different design. Not much to add here other than they are stylish, yet simple. 10/10
Build Quality
I would say this is a significant con. For $650 (I paid $549) these have okay build quality. They have the same generic build quality as the DT line which makes no sense. For $650 I would expect more metal, but instead...there is plastic. Had the mesh been metal, I wouldn't be writing this, but it's plastic. I certainly don't think this will be falling apart or breaking any time soon, but I expected more. I could just be picky here, but I really do expect a premium feel for a premium price. 8/10
Sound
Overall, this is a quality oriented pair of cans. These are not neutral by any means. They are hot, and they can be sibilant to some. The treble on the DT990s only bothered me slightly on some tracks. For these, they tend to bother me a bit more in general, but it's nothing to complain about. The biggest thing about these cans are what you put into them is what you get. They are extremely transparent, and will give you what you want, this is a massive pro as you can do what you want with the sound to make it sound a certain way.
Treble
As previously stated...these are hot. The treble can be harsh to those who are sensitive to it. With a little EQ drop in the treble, this potential issue is fixed. Upon being fixed, the treble is airy, and crisp. It does exactly what it should. I cannot really go much into it as I really don't pay attention to the treble, but I would say it does treble well and that listening to it without an amp/DAC or whatever else, the treble is going to be the most present. 8.5/10
Mids & Details
Mids...I really don't pay much attention to these, nor am I familiar with many terms, but from what I can hear these are very present. No matter what situation I have put these cans in, the mids were definitely there, which I assume would make them "forward". As far as vocals go, this pair doesn't do as well as the DT990s, but vocals are still done very well. I think the 990s had an artificial boost to the mids that gave vocals a better sound, but I am unsure. The vocals seem very natural and as they should with the T90s. The mids are just behind the treble when just listening to them and nothing else. 9/10
Bass
The reason why I love these is that they can take a massive boost to bass. If you don't want a whole lot, they can do that, if you want a lot, they can do that. They can't go to an XB1000 level, but they can definitely do bass. Out of the box, they have some thump, but it depends on the song. As I said before, what you put in is what you get out, and that is definitely true for the bass. Compared to the DT990s, they have less bass overall, but can handle a lot more. There really isn't much to say here other than it can handle a lot. It really depends on what the song has in it and what you want out of them. I can say these are not basshead cans out of the box, but can be if you amplify and EQ them to act like basshead cans. Although, don't expect anywhere near the same bass levels as heavier basshead cans. 9/10
Soundstage (& Imaging)
This is where I was a little disappointed. The DT990s has a wider soundstage, but these have a deeper soundstage. Personally...I prefer a wider soundstage. That being said, these do not lack soundstage at all. They are wide to the point where they need to be, but sadly, not any more than that. There's really not much more to say in regards to soundstage. As for imaging, I am not familiar with imaging, but I can say it definitely is there. I personally think the DT990s did a better job of this, but you can definitely tell where things are with these, that's really all there is to it. 8/10
Leak
Open headphones leak...that is fact. In comparison to the DT990s, they leak more. I could put a more dark EQ on the 990s and put them on 50% volume and have them not leak much at all. These won't do that, but it will help. I wouldn't advise listening to these in public since they leak quite a bit, especially considering the treble is higher on these. These are definitely more open than the 990s, that is apparent. At 25% volume with just my DAC, I could hear the music from about 1 meter away. Where as, with DT990s I kind of could, but not as much. They aren't really loud and obnoxious, but people could hear and maybe make out what you're listening to. 8/10
Isolation
Again, these are open, so isolation won't be great on these. With my DAC, amp, and EQ on 25% volume, I could hear my TV and make out what what being said when set to a volume of 10. That is slightly louder on my TV, so the isolation is definitely not great. With that being said, don't expect isolation from these unless at volume where leak is an issue. 7/10
Drivability/Impedance
These are rated at 250 ohm, so that means they're harder to drive...right? Not these babies. My Note 3 was able to drive them with more than enough volume very easily. The Note 3 may have an amplifer (not sure) but they can be driven with a cheap amplifier such as an E6 like I am using. 10710
Final Thoughts
Overall, I greatly enjoy these headphones. There really isn't much else to add that I haven't already said. These headphones are like a little soldier. They do what they're told to do, and I think that's how the Tesla driver is designed. Beyer says they're "precision" magnets, and I definitely agree with that. They deliver the music how it's meant to be heard by default, but are more than open minded as to EQ and amplification. They lean heavily towards enjoyable rather than analytical. From metal to rap to pop to EDM to screamo there wasn't anything they couldn't make sound amazing, I am impressed.
I would highly recommend giving these a try. While they are expensive and not everyone will have the pleasure of trying them (which is why I listed price as a con) they are worth every single penny I paid for them. I am extremely happy with these, and am excited to see what else Beyer can do with the Tesla drivers.
Overall rating: 9.5/10
TL;DR - These are a very transparent pair of cans that can make anything sound amazing. They do what is asked of them without compromise. They may be expensive, but they take music to the next level.
