Superlux HD-668 B

Average User Rating:
  1. atapgenteng
    "Cannot be used on extreme freq below 125hz"
    Cons - Cannot drive extreme bass freq
    This, headphone has weak performance on extreame bass respond (especially for editing movie sound tracks), i was return it back to the store after couple hours, and then compared it with the "new three" same model, but the sound are same, so i changed my order with sennhesier dj headphones, but none was better (superlux hd 668B & sennheiser hd 205) was cannot drive extreme bass freq. I also owned headphone from mice manufacture called "Genius", and my model is hp-04 live, this headphone was cheap, below "$20", yes the overall sound is bad!, but this headphone can drive extreme bass freq,
    If your source cannot deliver extreme bass performance, so i guess the others user reviews is right for you.
  2. CptKlotz
    "Quite good for the price, but not a "giant killer""
    Pros - Feels solid, can play very loud, comfort, detachable cable, good value
    Cons - exaggerated bass and treble, sibilant, looks a little cheap
    I got my hands on an HD-668B today...

    I still wonder what's up with these AKG clones... Is Superlux paying license fees to AKG so they may use their classic K 240 design for their headphones? One could certainly think so since a reputable dealer such as Thomann in Germany is selling them and they probably don't want to anger the Harman group :)

    Let's have a look at the headphone itself...

    The earcups' construction certainly looks a lot like AKG's K 240 design that has been around for ages. On this one, the outer headband is a little different and instead of an inner headband, it has "wings" with cushions that rest on the head.

    The build quality and materials feel pretty solid but look a little cheap compared to a real K 240 (though not bad for the price!).

    The vinyl earpads seem a bit thicker and more dense than AKG's. This may not be such a bad thing as the baffle of real K 240s tends to press on my outer ear after a while. Real AKG vinyl or velours pads can be used if desired.

    The cable is detachable and the headphones come with two cables that are 1m and 3m in length. This is a nice touch, especially since the two cables can be combined, giving you 3 lengths to work with.
    I don't, however, like the "connector" on the headphone that much. On the left earpiece, there is a thick piece of cable with a TRS plug attached to it. Since the connector on the earpiece is flexible, it is likely that the wires inside will break after prolonged use, thus requiring soldering. This does defeat the purpose of having a detachable cable in a way.

    I'm giving the headphones only one star for "design" because you can hardly call it original.

    So... how do they sound?

    These phones have been called "giant killers" but I'm not sure I'd subscribe to that theory.

    Compared to a K 240 Studio, the 668B has more bass and treble. While this isn't totally excessive, I wouldn't really call this headphone neutral. The treble response tends to make sibilant recordings sound a little unpleasant and I would prefer a flatter bass response (in fact I prefer a K 240 DF to the Studio or Monitor versions).

    Due to the somewhat exaggerated bass and treble, the midrange suffers a bit and voices can sound a little thin.

    All in all, the sound isn't too offensive, though and the headphone seems to be able to play really loud with little distortion.

    As always, take my description with a grain of salt since your HRTF or head shape (or taste) may vary :)

    I'd say for the € 30 they cost around here, these phones aren't half bad. At less than a third of a the price of the K 240 S (still available in some shops), I think they're a good value.

    Would I get one for myself? Probably not, since I do prefer a more neutral sound and I also like the quality and full spare part supply of real AKGs.
    People who are not audio geeks or who don't mind a "fun" sounding headphone will probably be quite happy with the Superlux.
    I find it a bit hard to translate my opinion of these phones into a star rating.
    I think 3/5 for audio quality is fair since there is definitely room for improvement.
    As an "overall" rating, I also can't really give it more than 3/5 since I wouldn't personally buy it.
    I think for value it does deserve the full score since the user does get a solid product for a pretty low price and most people probably don't mind a little bass and treble boost at all.
    jrpko likes this.
  3. crinacle
    "Definitely underpriced. Best in its price category, period."
    Pros - Very clear and transparent, big soundstage, excellent instrumental separation, sweet midrange
    Cons - Big, highs can be a little too much, slight grains in the high frequencies, the guilt that comes after realising how much you paid for it...
  4. bitlisz
    "Best headphone under 50 USD"
    Pros - Neutral
    Cons - Neutral (boring to someone)
    Sounds for me quiet neutral and well balanced.
    The comfort maybe not perfect, but reasonable (better than you can expect for this price)
    I added AKG Velour earpads for 25 USD.
  5. JRKO
    Pros - complete frequency range, tight sound, comfortable even for BIG heads!
    Cons - cabling options
    Just plugged these into my Audiotrak Im-Amp and they sound great straight out of the box.  Based on the sounds I'm hearing now I'm selling my HD650's and recouping/releasing the funds for other interests.  
    To my ears, they really are that good.
    I have a BIG head and found the clamping force of the HD650's rather tight but the HD-668B are comfortable from new.  I might get some plushy pads for an AKG or something to reduce the sweatiness the faux leather pads will no doubt induce.
    SOUND: Straight out of the box they have a more complete sound than the HD650's.  Maybe its the lack of the Sennheiser 'black' veil?  I think its probably a slight lift in the mid-high frequency range.  But thats fine by me as the so called 'telephone band' is where we as humans are most sensitive.  Bass has been said to be light but I put this down for the fuller mid-highs.  
    Insight is incredible, given the price and obvious effect it has on build quality.  On the first 2 or 3 songs i played I noticed things I'd not heard before.  Notes played on 'real' instruments begin and end just as you would hear a real instrument to do.  Vocals never seem to push into sibilance which I found an issue on some recordings with the HD650's 
    As noted above, these are good enough for me to have sold my HD650's  
    BUILD:  Lots of plastic, but are 'high end' phones really any different?  Not really.
    My only real bugbear is that the cable options are rather limited as the HD-688B have a 3.5mm jack on the left hand cup and you have to connect a cable from there.  Sure its easy enough to make one up but I'd like to be able to wire straight up to the driver.  Never mind - for £35 inc shipping I cant really complain so I'm off to listen to them again.
    GIANT KILLER? Maybe, maybe not.  But good enough to leave the £300+ phones alone for a good long time.  
    Lets call them 'THE BEST ALTERNATIVE'
  6. dweaver
    "A solid performing headphone with a bright sound signature"
    Pros - Tight bass, mid-range is nicely detailed, treble is bright and sparkly
    Cons - cable is not horrible but just so-so, bass is a bit weak in authority
    These are a very comfortable headphone that is also light on the head. The pads are bice but a bit cheap feeling. The overall design is solid though and they feel like they would stand up to regular use without a problem.
    Sonically they are a brighter signature than what I like:
    The treble is the best aspect of these as it is detailed and articulate without being sibilant.
    The mid-range is nice with decent detail but is not rich or warm enough for my tastes. Others might find the mid-range nice and neutral though.
    The bass is is tight and fairly deep but lacks volume for me. But again other might find this nice and neutral.
    The sound stage is about average in my opinion, neither large or small. If I was to make a comparison I would say it is slightly smaller than the HD600.
  7. padam
    "Good for the money"
    Pros - Very cheap, good imaging and clarity, detachable cable
    Cons - Boring mids, lack of extension at the top and bottom, not very energetic
    A surprisingly capable headphone under 60$ (which includes the AKG velour pads, much more comfy and changes the sound slightly and some useful accessories are provided in the box as well) with a reasonably balanced and detailed sound and it sounds surprisingly clear at its price point which is impressive at first listen. 
    But it is far from perfect: it is let down by a midrange that is thinner than I'd like and that it is not a very energetic or extended sounding headphone. The soundstage could be bigger as well, although the imaging is very good. And the build quality isn't anything to write home about.
  8. Airwin
    "Nice price, and best value in this range"
    Pros - cheap
    Cons - built
    No doubt, the 668 is a great value.
    The sound is on par with some 200$ cans, and therefor really impressive.
    But it is far from reference headphone level, specially the mids and balance are not even close. Built quality is surprisingly good for the costs, but still flimsy and made out of rather non elegant materials. The cable plugs are a nice gimmick.
    Is it a winner? Definitely!
    Is it close to Beyer 880 or Senn 600 class? No, the 668 sounds really good for 50 Ohm type, but it is far from the constant quality and the comfort of the upper class.
  9. WrxSTI
    "You get what you pay for"
    Pros - Neutral, revealing, precise, lightweight, sturdy, cable features
    Cons - Strong clamping force (gets better with time)
    As the saying in the title goes, this has never been truer than for these headphones.
    Thankfully, Superlux sells sound quality, not an overhyped brand name. Can you really get great sound for $40? Oh yes, and it's right here.
    I was recommended these headphones by a fellow forum member and after a day or two of investigation I decided I really liked what I read about them and figured if it was true, then these would be the best headphones I could buy on my really limited budget. So, I did.
    Before I give any impressions, a small disclaimer: My previous headphones were Trust HS-6200 5.1 USB, and Trust Multi Function Headset 310. The most "hi-fi" component I have in my house is a set of Logitech Z-5500's. They run via coaxial, while everything else runs from the motherboard Realtek ALC889 codec (best Realtek codec, but still onboard.) So, I have not had much experience with quality components, but I know how to trust my ears. Hopefully, this will be enough to make a relatively accurate assessment of these headphones. Let's take it from the outside in.
    Design: Well, the first thing that surprised me is that they are relatively small. I expected them to be a bit larger from the pictures. The next thing is, they are really light, weighing only at around 200 grams, which is good as it makes them easier to keep on the head for longer periods of time. The build is fairly sturdy and the plastic is of good quality, they look like they will last long. I'm not going to comment much about aesthetics, aside from the "Studio Monitor" labels being a bit tacky, but I generally like the way they look.
    Comfort: A bit on the tight side. Causes my ears some discomfort after having them on for a while (upwards of 2 hours), but after a few minutes break it's good. I've read some people claim it made their ears sweat and heat up, I haven't had those problems but I don't normally sweat much anyway.
    Accessories: With these headphones you get a 3m cable (for PC use) and a 1m cable (portable use) which you can exchange and even combine together. You also get a 3.5 (1/8") to 6.3 (1/4") mm jack adaptor, which is a nice feature, and a carrying pouch to, well, carry them around.
    I liked the cable flexibility the most, I think it's a great idea.
    Sound: And here we go, the most important part. I'll try to refrain from analyzing these headphones in the typical fashion here such as how the "highs, lows, mids, etc." sound as I don't think I'm familiar enough with the terms here but I will attempt to describe their overall sound signature with my limited experience, so here goes. What you play through them is what comes out. A bad recording will sound bad, a good one great. They are really transparent, simply "passing on" the sound without leaving a hint of presence of their own. And honestly, I like this. I want to hear my music the way it was recorded, intended to be heard. I don't want headphones to change my music. Sure, colored headphones may make it sound more "fun", but that's not the way the artist heard or made the track. Well, to each his own I guess. To continue: they reveal a lot of detail. A lot. Background hiss, noise, breathing, coughs from artists and stuff I have never heard before in my music. I have to play through everything again, to rediscover all those tiny details I missed out until now. The frequency response doesn't have many spikes, and it corresponds with what you can see on the manufacturer's website.
    Soundstage, well, it's generally good. Certainly better than the closed-back headphones I own. These are only semi-open however. Sound isolation is still OK, I can hear myself typing and my noisy PC case, but when music plays it's hardly audible. To sum it up for the Superlux HD668B: Add nothing, reveal everything.
    Oh, one more thing: the bass. I've seen a lot of people claim the bass isn't strong enough, while a few claimed the bass was good. And I believe I know why. It actually depends where you plug them in. If I plug them into my PC case's front port, the headphone out on the Z-5500, my cell phone or MP3 player, the bass is overwhelming, in fact there is more bass than there is in the 5.1 headphones that had a dedicated subwoofer inside, and it certainly does not sound natural. However, if I plug them into the rear ports on my motherboard where there is supposedly a headphone amp the bass tames down by around 80%.
    EDIT: After a bit of longer listening, I've realised that it's not the amount of bass that changes. It's the amount of mids and highs. The thing is, the output ports on the back of the motherboard are assignable. If I set the jack to "speaker out" they give a line level signal, and the headphones sound substantially less clear and you have to turn the volume up from 35 to around 80; this gives the impression that the bass is louder - it's not, it's only that the signal is not strong enough to drive the mids and highs up to point. When switched to "headphone" setting, the headphone amplifier kicks in and the higher frequencies -really- jump up, leaving the bass behind at the "normal" level. This is why it seems it has less bass. So even though these headphones are only 56 Ohms, they certainly benefit from amping, and well at that. Line-level won't cut it.
    Overall, I am extremely happy with them, will keep them around for a long time. My next purchase is going to be an Asus Xonar Essence ST, I can't wait to hear what they will do then. Well worth the money I paid for them and more, and would recommend them to anyone in this price range, for sure.
  10. Marlene
    "Impressive, just impressive"
    Pros - dynamic, deep bass, relatively balanced, analytical, good soundstage, very inexpensive
    Cons - slightly recessed lower mids
    I won´t repeat what everyone else wrote before - because it´s true. I´ve listened to a Beyerdynamic DT990 once and while I love my Sennheiser HD-600 a different cup of tea would be nice sometimes. But then, Beyerdynamic headphones are a bit too expensive for the sole reason of being able to listen to "another flavour". Thank God there is Superlux. You´ll get so much material for your money. You´ll also get very good, Beyerdynamic-like sound. You can even improve the sound if you replace the pleather earpads with the velour pads for the AKG K-240. I don´t know why but they sound a bit more balanced and refined with these earpads. Further improvement can be achieved by putting paper tissue between earpad and cup (increases the distance from ear to driver and will likewise improve comfort).
    If you do these two things you´ll get a headphone that will rival headphones for 150-200 Euros: they are dynamic, precise, crisp, balanced with a very good soundstage. They are easy to drive but they will sound best with good amplifiers. They won´t be impressed by loud or harsh music, they will just play along with just the right amount of directness. Some people would argue that this makes them sound a bit "bored" - which sounds almost insulting to me because they are anything but boring. People seem to confuse balanced sound with boredom. Well, let me put it this way: if you want your headphone to colour the music you´re listening to... go and search elsewhere. The Superlux does indeed add a bit colour (around 7.000 Hz) but it´s not very much and it´s not distracting. However, lower mids seem to be a bit underrepresented - but I could be fooled about that because I´m accustomed to the comparatively (to the Superlux) warm mids of my HD-600.
    All in all, very, very good for the money. A true bargain, thank you Superlux.
    P.S.: before I forget... they need considerable burn-in time to sound their best.
    Dreddguy, cbf150, alejandro7 and 4 others like this.