Pros: Comfort, Build quality, Pleasing warmish neutral sound signature, Easy to drive, Not source or amp finicky(also a con)
Cons: Grainy and veiled sound, Limited scalibility, Lacks refinement, Not the most coherent
Sony MDR-MA900 Review
In the past I compared the Sony MDR-MA900 to the then similarly price AKG K612 Pro. I'm doing this review because I have the MA900 in my possession for a certain amount of time and I came to a better understanding exactly why I felt the way I do about the MA900 compared to the K612. I currently use the K712 as my main headphone but it is quite different sounding than the MA900 and I feel the MA900 is better compared to my HD 545 and K612 than the K712. The systems I am reviewing the headphones on is the HRT Music Streamer II+ as the DAC and both the Hifiman EF2A(with stock tubes, RTC tubes, Siemens tubes, GE tubes, and RCA tubes) and the FiiO E12 as well as many other sources such as my laptop, iPod Touch 5th Gen, etc. This is going to be a relatively short review as I'm going to get to what I like about the headphone and what I think it does well and what I don't like about and what I feel it falls short at.
I'm going to state this now while the amps have minor impact on the sound, it's not really going to make or break the sound like it does on my other headphones. The sound does get cleaned up some with better systems but nothing that drastic as say what happened to my now dead Sennheiser HD 555 which honestly outclasses the MA900 when amped well, the HD 555 has since been replaced by the superior yet older HD 545. As long as the DAC is good enough quality it sounds relatively similar on anything. This likely has to do with the impedance resistor and in fact most of my issues with this headphones sound may be related to it. The problem with the lack of scalability is that the higher you scale up the gear the worse this headphones sounds comparably to other headphones.
Comfort: This is the standout benefit of this headphone, it's just a featherweight with very mild clamp but is also secure on the head. There is an amazing sense of breathability and they can be worn for hours easily. Some minor quibbles with the comfort is the pads take some getting used to, the headband is sort of small so it may bother some at first, and it needs to be adjusted so the ears don't really touch the drivers.
Tonal Balance: I think one of the best things about this headphone is it's tonal balance, it has a very nice tonal balance, neutral and laid-back with a slightly warm touch to it, which makes it an pleasing and musical headphone that does well with most genres of music and it's a bit on the forgiving side so this makes it good for a variety of recordings.
Build Quality: Contrary to initial reports and suggestions I find the build quality of this headphone to be really good from the actual housing design to the cable itself. The lightweight build suggest heavy cheap plastic use, but this headphone felt well-built from when I first had it in my hands, it also has a good amount of magnesium alloy in the outer grills and yolks, the headband pad area also seems to be reinforced with metal. The cable was a concern for actual worry at first and it does seem to lack some strain relief on the plug but the cable is far sturdier than it appears and it retains no memory, the pair is about a year old and has had the cable run over numerous time with a computer chair and the cable shows no marks of scuffing, the headphone has also been dropped a few times with no marks or anything. These things seem to be built to last.
Soundstage Presentation: This headphone has an amazing soundstage presentation, it has one of the most speaker-like soundstages I've ever heard from a headphone and that's something truly special about this headphone. If someone is looking for a speaker-like sound, it doesn't become much more speaker-like than the MA900.
Easy to Drive: This headphone takes very little work to make it sound how it should or it's best because it sounds relatively similar on just about anything with the biggest improvements seeming to come from the DAC. This is a wonderful headphone for those who don't want to fiddle with amplification.
Transparency & Clarity: This is what I found to be the headphone biggest and most notable flaw and it's what led me to let it go. All other flaws are relatively minor compared to this one, so I'm going to just focus on this con of the headphone in the review. I'm just going to state it simply this headphone is veiled and grainy. There is a veil and grain throughout the entire sound. This wasn't a big deal when I first got the headphone, but after a while and especially after getting other headphones and upgrading my system more this problem became a bigger and bigger deal. The constant grain that seems ever present in the range, mostly midrange prevents this headphone from having a black background and seems to mask some of the more subtle musical cues and details in a recording. Once I started appreciating and grasping refinement and things such as transparency, a black background, musical depth, etc. better; I started to like this headphone less and less to the point where I have trouble listening to it. I believe it's simply a case where my standards and preference of sound causes me to stop being able to appreciate this headphone much anymore.