Exceptionally good sound and build quality for the price!
356669
I'll be the first to admit that I didn't know what to expect from these...
I use them with a Quality Turntable (Audio-Technica LP120) and with my LG 4K TV through the optical input.
My musical Tastes: Heavy Metal, Rock, Blues, and Classical.

PROS:
- These sound exceptionally good for the price! (Sound is so subjective, but The range and 'headroom' were very nice)
- They get 'Uncomfortably' Loud without noticeable distortion.
- The bass response is also very good.
- All the inputs are useful and worked flawlessly... TIP:  The two RCA input pairs have different input sensitivity, check the booklet.
- The Fit and Finish was far better than expected.

CONS:
- The Remote is a TINY IR Remote, which feels very cheap.
- The indicator LED (in some modes) is difficult to see with the Dust Covers in place.
- No Sub-woofer Line out option for an additional powered Sub.

I'll be buying an additional pair soon.  Powerful, compact, and very affordable!
3155029
I just received these magnificent closed back works of art today and was blown away by the size and build quality of these headphones. After unpacking them from the "cool" box they came with, It was time to take them on a test run using the Samsung Galaxy S4. First impression, the sound quality was very good but not the best I've experienced. The bass was a little flat, the mid-range was non-existent but it has nice crisp highs. I use "Google Play Music" which has an equalizer,bass boost and a surround sound feature. Once I got the sounds tailored to my preference,all I can say is Wow!!! The equalizer took the sound quality from being very good to dynamic! The 2" (50mm) drivers can handle all types (genres) of music and the closed back design keeps out most annoying outside noise so that you are basically in your own little world. As for the in-line microphone and remote feature, it's made to work with
iOS devices (iPhone,iPad,iPod etc..) but can work with Android OS. When using this model with my Samsung Galaxy S4, I was able to make and receive calls with no problem but the volume up/down did not work even when listening to music. That's the only trade-off. The fold flat design comes in handy when transporting these huge headphones but it would have been great if they came with a carrying case of some sort. I guess you can't have everything. Overall I find these AKG K551's to be a sound investment that should last for years to come. AKG has an outstanding reputation. Enjoy!
1845582
These earbuds are an unbelievable value for this price point.  My husband was reluctant about this purchase because he had never heard of the brand, so naturally I went ahead and ordered them.  They surprised me with their ease of use (pairing with my Samsung Note 3 phone could not have been easier!), the rich sound quality (deep, booming bass), and overall sleek, comfortable design.  I must have small ear canals, because the default size rubber ear domes would stay in my ears but be very painful to remove (and I have to pull them out of my ears quite often because I wear them at work, and my bosses are constantly stopping by to yap with me about something or other)  I solved the problem by simply switching out the domes with a smaller size that came with the earbuds.  Now they are quite comfortable.  I love the fact that the volume controls and power button are located on the neck strap, and that the buttons are large enough that I can push one without having to remove the whole thing to see what button I want.  My music sounds incredible on these, I really am amazed at how great they sound!  I can get about 4 hours of continuous use before having to recharge them.  The included charging cable has only a standard USB port on the end, so you will have to find or purchase one of those ac wall unit prong things that a USB can mate with.  Overall I am very satisfied with this purchase.  Even my husband has to admit that it was money well spent.
1255094
Very impressed with sound quality. This is definitely what you would call a high value purchase!
4058825
Being sort of an audio-aficionado (won't go as far as calling myself an audiophile) I got these for my girlfriend.
I used as comparison a set of Sennheiser PC360's. She uses them to listen to ASMR videos and listening to music.

These are definitely well built, slightly on the heavy side for my taste. The finishing and build quality is higher than I would expect for headphones in this price range, they feel sturdy.

As far as comfort: Other than the weight, I think they sit perfectly on both head and ears.

Sound quality:
BREAK THESE IN! Just plug them in and let them play for a couple of hours, repeat. These guys are the perfect example of how much of a difference it makes when you 'break them in'. Plug them in, put them on, play a song, listen to it... remember all the stuff you had to 'complain about'... boomy bass, lack of definition on higher mids and highs.... listen to other stuff an hour or two, go back to your first song. It makes a WORLD of difference.
Overall, I believe the sound quality is excellent. I think they deliver a very 'full' sound. If I had to pick something to complain about it would be that the mids sound full and encompassing but not as well defined as the highs and lows.
I don't think I have ever heard anything like this in a similar price range.

A big plus is the portability, they fold nicely, come with a case and have a coiled cable.

Definitely buy!
4125125
I wouldn't say I'm an "audiophile," but I certainly appreciate good sound and have heard dozens of good headphones and speakers and can easily tell the difference between good and bad sound. I've been on a search for a great pair of, hi-fi like, sounding wireless "on the go" headphones for a while and nothing has met my expectations until I got these. I've had the Harman kardon bt's for a couple years, which sounded pretty good and natural but weren't comfortable at all. Recently I got the highly regarded sennheiser momentum 2 wireless with noise cancellation. For $400 I wasn't impressed at all with the sound quality and don't understand why the reviews are so good. They sounded "good" but nothing special for the price with just average mids and highs (although great lows), but no where near as good as a pair of good hi-fi cans connected to a good amp, such as my akg q701's connected to my nuforce icon hdp. I decided to pick these up on prime day (for $300) and I have to say I'm very impressed. I know making buetooth headphones sound like a pair of good wired headphones is a big challenged, but bang and olufsen nailed the sound to me, it's nearly perfect. Great blend of highs that aren't harsh, mids and lows that don't blend together, overall they sound fairly true to the track. They really do sound more like a great pair of wired hi-fi headphones and I think are definetly worth it for what I paid (maybe the retail price of $450 is a bit steep). They're also extremely comfortable and I feel like I could wear them all day, even the touch controls on the side work fairly accurately, except for the volume control which can be a bit finicky. They're also built incredibly well, like the interior of an extremely high end car while looking great, but not super flashy which I like, oh and the battery life is awesome. Really the only complaint I have it the included case, which is just a soft bag. For the price I really think they should include a nice carrying case like my sennheiser's did, and maybe the price, but if you're willing to spend the money, I don't think you can get much better sound from wireless headphones. I can't wait to try them wired with my amp and dac!
4544490
These are absolutely awesome for the price.  Great construction quality with full metal housings.  The speakers have weight!  Smooth and solid feeling volume control.  The sound is surprisingly rich and loud for small USB-powered speakers.  The cables are nice and long and easily span my large desk with two monitors. I would HIGHLY recommend these!
44069
I've had these for about a week. These headphones easily compare to "professional studio-quality IEMs" worth $100.  I was flabbergasted when I experienced how much punch and detail these IEMs deliver (make sure you turn the volume down a little!) What a steal!  Easily puts Klipsch S3M and Hifiman RE400 to shame, absolutely destroys the MEElectronics M-Duo (worst $40-$60 pair I ever experienced in 7 years), similar quality to Yamaha M100!  Slightly more detailed than Brainwavz variants imo (which are also a great line-up, mostly for rock/metal).  It would be a lot better if a microphone was included, and I would pay an extra $5 or $10 for that feature.  Would highly recommend it as a backup pair, even as a daily listening pair.  They fit marvelously with comply earbuds.  I hear mostly metal with them, but they work well with synth and bass-heavy music too.  Minor microphonics with cable, love the cable build too: it's a nice metallic-mesh quality, wrapped in plastic.  It seems very sturdy.

The IEMs seem rather sound level.  I would almost say it's neutral, but it also provides a rather exciting listen.  This is in part to the surprising amount of audio detail that these am800s provide.  You will hear Everything Clearly!  They are aggressive too!  In comparison, the M Duo's are absolutely distorted and murky, making for an awful listen.  S3m and RE400's are rather dull and flat-sounding, and it's really hard to justify the RE400s cost (was $70 or $80 for RE400s at one point w/ weak build quality, and now the Duo's are MORE [$70-80$] ?!?!  What a sham!).

I hate the headphone case (little leather pouch).  I much prefer the soft-but-firm, slightly hard-shell zipper cases with pockets, just like the Brainwavz cases.  Not sure if I like the L-shaped jack.  I think the straight jack would be better.  At least the jack is made of metal, just like the housing for the drivers.  Again, excellent build quality.

I'm considering buying another pair, or even two, right away!  Get these while you can.

Summary - despite minor annoyances like no microphone and slight microphonics, it more than makes up for that with superior audio quality that I have NEVER heard in this price range before.  You would be crazy to avoid these.  Stop looking around - buy them now and experience it yourself!
677147
Definitely a very nice sound quality and build quality for the price of this headset. Great bang for your buck!
2242261
These cans sound MUCH better than I was expecting.  Just as clear as my Focals and KEFs, and a nice sparkly top end, with a robust but controlled low end.  Truly enjoyable to listen to.  And the wood finish is beautiful.  The headband is not as easy to adjust or as smooth as some other headphones I own, but still very workable.  Build quality feels solid.  I am using these with a COWON S9 and a Fiio and Topping amps, as well as hooked to my home system, which consists mostly of Marantz and Emotiva equipment.  For the price, you ABSOLUTELY cannot go wrong with these.  Glad I got them.
2514346
Excellent sound quality, great item, especially for price.
16659
These are the first pair of over-the-ear headphones I've ever owned, and I have to say that they exceeded my expectations for the price. I originally wanted a pair of Sennheisers, but couldn't afford them. Plus, I bought these mostly for online gaming, and Sennheisers are a bit expensive for that. My only complaint is that the bass could be a little deeper, but since I'm not blasting Dubstep with them, it's not a big deal. A+

I've loved these so much that I bought another pair for my brother to use. He too has been impressed, and called me with them while walking around NYC. The sound quality of the microphone was impeccable and the lack of background noise only furthered my adoration for these headphones. Well worth the money!

*Edit* The bass is just fine! The problem was on my phone's end. The standard Android music player has terrible bass, and doesn't have an option to increase it. I use&nbsp;<a data-hook="product-link-linked" class="a-link-normal" href="/Music-Player/dp/B017NDIK6C/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Music Player</a>&nbsp;now, and the bass is deep and rich.
3493129
These headphones sound fantastic; much better than others in the price range (naturally, I'm excluding the studio-quality Sony, Koss, Sennheiser, and others). There are many comparative headphone reviews out there; I challenge you to find one more well-regarded than these for under $30 (including Sennheiser's entry-level options).
The bass on these headphones is deep and powerful, the highs have no rattling or other distortion, and the midrange is clear and full. I've never heard most of my music with this kind of fidelity before--and I can't go back to inferior headphones after this experience! An excellent buy, I highly recommend this product!
481808
I'll start by admitting that I have sorta a headphone fetish.  I've spent way too much on headphones in the last 10 years.  I mention that only to qualify that I know what to expect from headphones at given price points from $20 to $1000.  At the $30 I paid, I expected nothing more than the novelty of wireless headphones for my TV and iPhone.  I gotta say though that I was amazed with what I got.  Now, the build quality isn't what you'd get from Sennheiser, but the sound quality would cost you > $100 from Sennheiser.  Really nice bass and mids.  Rolled-off highs, but not enough to take any of the sparkle away.

If these were wired heaphones, they'd be a an excellent pair of cans -- the best I've ever heard in this price range.  But, given that they are wireless -- and can control my iPhone, these are an absolute steal.  As soon as I can order them again, I plan on getting another pair for home, since these have found a home at my office.  The freedom of wireless is really nice when I need to walk to the printer.
1331440
First and foremost, the sound quality on these are fantastic. The sound clarity and frequency response are all absolutely top-notch. Very well may be the best-sounding pair of headphones I've ever owned, without exaggeration. The build quality is stellar. They feel - and look - incredibly sturdy, and are COMFY! These aren't just tolerable, they're actively enjoyable for me to wear.
The microphone is bendable, with a high degree of adjustability, and it allows little-to-no background noise in. My wife and I tend to game together in our small living room, and when she and I are yelling at super-intense moments, there is very little cross-talk.
The cord-mounted volume controls are excellent as well. The sliding wheel allows you to do very fine adjustments, so that everything is juuuuust the right volume.
These have legitimately transformed my wife's and my gaming experience. I hope I get many hours of ancient defending out of them.
357370
fantastic bang for the buck! the driver in the sennheiser HD 518's is very advanced. these are great audiophile grade headphones  for someone just getting into audiophile quality. the bass is a little heavy on these, but that's a guilty pleasure for me :)
4811198
This Headphone is an amazing headphones all around!

It is built at extremely premium quality with desirable looks and very comfortable ear cover. I cannot say enough good things about the build quality. It feels comfortable for long usage times ( I enjoyed 2 hr music and it was still cozy to wear ).

Of course the sound quality is what really matters for a headphone. And it did not disappoint me at all. I would say the sound quality matches the premium feel and look of the device, offering excellent performance at all ranges.  The bass is amazing and even can compare with my 200 buck AKG headphone.

This is a gift to my daughter and she is absolutely in love.  Recommend this product without reservation