*review this right after i have this headphone. burn in test not yet available
**I will add more info after i receive velour pads ordered online. any changes in sound or improvement, will be added
Lost my AKG K403, my very first HD headphone (to me). Very low on budget, found this, bought it, waited for a near month, worth the wait. (was aiming for portability but... this price is so really pushes me to this)
 
This is my first over-ear audiophile headphone (well, not my first but for mainly music, this is my first) ever to buy and i didnt actually expected that if i didnt lost my AKG...

*I would guess that this is the 2nd badge of the HD681. differentiable by the position of "2x32ohm" print*

1. First Impression (well, i use Galaxy SIII camera, set ISO-800 just for less blurry. so, lots of noises)

Well, the packaging is what i would say, an item from a junkyard store. I dont know if the rugged packaging is due to the shipping or is been like this, but for sure, the package is really cheap. and is exactly a piece of plastic bag wrapping a piece of cardboard (slice)
 
 

Looks horrible
 

Well, i didnt pay attentioned to the colour (just like my first phone...) when i bought this but truthly, this really doesnt look attracting. but personally, i kinda like the steampunk kinda style of the styling.
 

This also provided with a carrying pouch to protect the headphone. Though i would say that the pouch is like a cloth bag for carrying wet clothes.
 

By close up though, this headphone gives a fine detail to most of those pattern (though some imperfection of build is shown)

2. Comfort
Well, is not the worst but feels not too comfy. The pad is the worst feeling ever. My ear gets sweaty and hot (maybe because im not used to wear PU pads). Most says to change to other pads that fits to the AKG K240, preferably velour one. so i think i will. (will DT880 pad fits?)
Definitely do not wear this on your neck as you may be choked (lol). is just that the headphone just 'closes'.

Tight fit but not in the assumption of having your head sandwiched hard. But that tightness boosts the hotty and sweaty feel... Will try to loose it.

3. Sound
I would say, the sound is superb.
The bass is kinda just a bit stronger than my preferred but can be tuned down just a bit. But for sure, entire bass frequency area is really amazing~ Is tight too~
i tuned down to 62kHz@-2dB, 125@-1dB

[edit]The mid part is great. For the first time, i dont have to eq up a bit for the mid.
I can hear much more detail than before~
Well, actually, after a bit more hours, i just realised, the mid part is just, well, "audiable". is just a bit more than enough but not in a way of satisfying mids.
So, up a bit for 1dB or 2dB at 250Hz, 500Hz and 1kHz sounds more better. BUT that is just my preference. (the clicky navigation sound of the Windows when browsing is sounds more satisfying when eq-ed the mids up)
 
 
The controversial part, Treble.
Kinda sharp, but actually, not that much. maybe the 2nd badge did just a bit improve this. i eq this down, 2kHz@-2dB, 4kHz@-1dB, 8kHz@-2or3dB. after tuned, gives out some detail but also wash out some detail as well...

[update] Well, what i just did, i kinda use a tissue paper and that really reduces the sharpness of the treble. Well, mainly because i just want my ears to be less sweaty when wearing but that really improve the treble.

Yeah, looks messy for now. But i planned to change the pad to velour one anyways (almost one click away ordering dt880 velour pad, just a cheap one from Misodiko)
 

How the tissue covers the whole pad, absorbing those bad treble
 

Well, the tissues do their job well enough

This sounds really great if you have retro songs from the 60-80's. Tried Pink Floyd - Money, omg soo warm and retro feeling~
But, metal songs are to be avoided as the sharp treble will spoils the moment.

4. Overall
I dont know if this is actually an audiophile headphone (or even monitor) as this one has a bit coloured signature. but great to have though and pretty sounds natural to me

The best for the price. Highly recommended for another collection. Later i will try to compare this to my local available headphones like Beyerdynamic DTX910, DT880, T1, Sennheiser HD598, AudioTechnica ATH-M30x, M40x, M50x, Sony MDR-100AAP, 1A if i have time.

[update] is it just me, or DTX710 has more bass? also, HD 681 somewhat lacking of mids. i thought the bass of HD 681 is kinda more and stronger but, i didnt sense that once i tried DTX710, MDR-A1, MDR-100AAP. is like, well, the HD681 has deep bass but lacking compared to A1 and 100AAP. even DTX710 is somewhat a bit more stronger bass...
is this kinda.. true...? or is my ears playing my mind... or did my HD 681 just gone burn-in so soon? (well, i enjoyed too much of Sony MDR-Z1R, with DSD as well, so mindblowing)
[update2] i guess my mistake. yesterday i made my headphone loose enough that i just realised i've made some gaps between my head and the pad (back ear area), resulting less deep and underpowering bass. though, i really like this kind. will tighten once i receive my velour pads

*I was thinking of buying Beyerdynamic DTX710 before but, even with great price, i cant afford it. so i buy this. but.... waited for so long to ship here... and, the wait worth it

SO today is time to make a little review of a not so well keeped secret chinese monitor headphone Gem.
 

 
 
I heard about the Superlux headphones here on headfi and was rather sceptical of the sound they can produce, I was like yeah they are dirt cheap and could be great value, but how good at this price the sound can be? It can't be a serious sounding monitor, can it?
Well, when I finally see them at Gearbest store in sale for a more than ridiculous price I decided I have nothing to loose and who know as i'm a music producer perhaps I will really use them to mix some tracks...
And I finally put them on my head and begin to listen to a violin quartet and was like:
Okay, this headphones are not a legend for nothing, they deserve their most-buy reputation, this is serious cans with a serious sound, extremely neutral and detailed, light to wear and comfortable and I can really make great mix with them even if they cost third time less than my now gone Sony MDR-7609.
 
 
CONSTRUCTION, PACKAGE & DESIGN:
 

 
 
Package look like a dollar store joke and I was laughing first time I see it, thinking: their you go for your 20 boxes dumb head, what were you hoping for? A Miracle? Yes the package is a joke, it is not serious, it is a price cutter so you can buy a miracle! Just throw this in trash can and concentrate on headphones instead.The construction isn't bad at all for the price and make me think of AKG K240 on all aspect, HD681 just try less harder to look fancy with plastic piece but both are about the same construction taking apart the fact that the AKG have a detachable cable. So construction is all plastic but well assembled and extremely light tp wear wich make them very comfortable for long listening sessions. It do not use the kind of glossy plastic that is easy to break and I think durability isn't that bad because I do not instinctively fear to drop it on like with other plastic headphones I have. This type of construction, even if a little cheap, is incredible for the price. Clamping force is light and earcups are movable and take the form of your head.
 
SPECS:

1. Headphones Type
   Headphones - binaural
2. Headphones Form Factor
   On-ear
3. Headphones Technology
   dynamic
4. Sound Output Mode
   stereo
5. Frequency Response
   10 - 30000 Hz
6. Total Harmonic Distortion (THD)
   0.25% %
7. Sensitivity
   98 dB
8. Impedance
   32 Ohm
9. Diaphragm
   2 in
10. Magnet Material
    neodymium

 

 
SOUND IMPRESSIONS:
 
So, it is write 2X 32OHM on the headphones cups wich make them 64Ohm and a little hard to drive with average music players. For this review I use my Ibasso DX80 as well as my SANSUI amp with Ibasso DX90 line out. The Superlux HD681 can't be drive properly with Xduoo X3 and even less with ONN X5 or Ruizu X02. You don't know what this headphones are capable off if you do not have an amp or powerfull mixer. The HD681 are more easy to drive than the 128 Ohm Superlux HD681B but to get full sound, bass and air between instruments you don't need to crank the volume, just to give them the right power so they can breathe properly. When use with a powerfull amp the real deal begin, we are now blessed with a magificent and detailed sound with very wide soundstage and fowards texture and treble. There lot of air between instrumentation and separation of them are great because of this. The Sansui AU-D5 amp give some welcome warm to this rather bright earphones too, when listening to classical this is really a great headphone, we heard every details of violin player including breathe and bow microdetails scrubbing texture, the acoustic guitar chord is full of sparkle and we feel the fingers pulling every rope. The HD681 really hit higher than their price range and sound exceptionnaly good for this very reason.
 
LOWS:
The Superlux HD681 aren't basshead headphones at all and have the typical sound that we want from  a monitor headphones wich mean detailed, neutral with a good instruments separation. Bass isn't very round and heavy, even if it dig deep and low it isn't the type of bass we feel, tough with a powerfull amp it come to life and have more weight, this headphones will not be appropriate for IDM or rap because of the airyness presentation of the soundspectrum. Still, right now as I listen to Jamie Saft New Standard jazz album, Steve Swallow bass is very well rendered and every note clearly audible, when the drum take more place it is less clearly presented tough because the toms decay can interfer with bass decay. Anyway, the HD681 love (piano!) jazz and play it with great precision and energy, some albums can sincerly sound memorable with them.
 
MIDS:
Now I listen to the excellent Aventine album by Agnes Obel, her voice float around me and have great warm, texture and autority. Instrumentation is more foward than her voice but in an immersive way and has the voice is in the center of it we don't feel it is veiled or too dark. Another time texture is a little agressive even if it isn't harsh for the ears. Microdetails are foward too and the overall sound presentation lack a little roundness or softness to be truely mesmerizing-this is were the ridiculous price tag show his greatness limit. Anyway, the HD681 medium frequencies are very realistic and far from being in the backseat and the texture is welcome for extra resolution that can give more dynamic to some music. Violin, piano and vocals sound very good with the HD681 and acoustic music is a real joy because of the analytical presentation showing everything that is going on in a track, for the better and the worst. Because of this extra texture some signers voice can hiss (Beth Gibbons does this).
 
HIGHS:
This headphones have LOT of treble to share and are on the bright side even if a relaxed version of it. We have plenty of texture, microdetails and treble sparkle here, sometime it can even be too much of it. For exemple, if you listening to an old vinyl recording the background hiss will be too fowards and perhaps spoil the clarity of instrumentation. But if the recording is perfectly clear this extra treble will give extra details and texture to instruments, you will eaisly pick everything you want from a track as the neutral presentation with foward treble will give as much importance to cymbals than bass and guitar. I guess with very complexe and dense tracks it can became overwhelming for a proper musicality as every sound will be be pickable by the ears. I consider this as a must for monitor headphones tough, wich are use exactly to be able to calibrate every sounds and instruments in your mix.
 
CONCLUSION:
The Superlux HD681 are incredible headphones that can be use by serious musician as well as audiophile on budget that want a realistic and analytical headphones. They outperform way pricier headphones and are extremely comfortable for long listening. If you want a little more bass you can try the HD681B wich have a little more but are even more hard to drive. Superlux really impress me with their budget friendly headphones and earphones that have a real hifi sound and really deserve the admiration they already have.
You can find them here for an ultimately absurb 20$:
http://www.gearbest.com/headsets/pp_270782.html
 
LONG LIVE TO SUPERLUX!!!!