You can purchase here on Amazon for $39.95
The design is simple, reminiscent of AKG, and more importantly it fits almost every one. I've never personally had an issue with the wing system, though I've owned a few Audio Technica Headphones myself so I'm used to it.
On the plus side, the pads are also removable and easy to swap out! I've yet to change mine out, but doing so does offer changes to the overall sound, so for this review I'm using the stock pads.
Drive Type: Semi Open Back
Frequency Response: 10-30kHrz
Sensitivity: 98 dB SPL/1mW
Maxium Power Input 300mW
Impedance: 56 Ohm
Weight 7.8oz (222 grams)
Cable: Removable 1M & 3M
Plug Adapter: 3.5mm to 6.5mm (1/4 inch)
The Superlux HD 668B comes in very simple packaging. Cardboard box, with the brand and product name on the front. Specifications are listed on the back side, and the left panel has depicts what is included inside.
Accessories include a 1M and 3M female to male 3.5mm TRS along with soft plastic cloth carrying bag. Given the cost, I'm very happy to have the addition of the adapter and two cable lengths!
The design is simple, reminiscent of AKG, and more importantly it fits almost every one. I've never personally had an issue with the wing system, though I've owned a few Audio Technica Headphones myself so I'm used to it.
A detachable cable, and easier to power driver make it easy to pair the Superlux HD 668B with a variety of sources. I've enjoyed it with my LG V20, my Audio GD NFB10ES2 and even my New Nintendo 3DS. With each, the quality of sound and total volume was beyond sufficient. For music play back I've primarily used my HM 601, and I will be using that as my primary source for the sound portion of this review.
I also purchased a KetDirect 4.5ft BlueCloth cable terminated to a right angle 3.5mm, I happen to prefer a right angle 3.5mm for my needs and if you need something different you're free to upgrade and swap cables how ever you see fit!
With a $40 cost, I'm satisfied with the build quality of the HD 668B, the plastic is sturdy with some flexibility to it.
The wing system bends and allows the cups to place themselves just over the ear, and the ear cups also flex and rotate to further help with the fit.
My only qualm with the HD 668B is quality control, sadly my first pair had a very loud resonance on the left driver from around 230-250hrz. I simply returned that one and repurchased another pair from amazon. Thus far I haven't had any problems with the replacement.
I also purchased a KetDirect 4.5ft BlueCloth cable terminated to a right angle 3.5mm, I happen to prefer a right angle 3.5mm for my needs and if you need something different you're free to upgrade and swap cables how ever you see fit!
With a $40 cost, I'm satisfied with the build quality of the HD 668B, the plastic is sturdy with some flexibility to it.
The wing system bends and allows the cups to place themselves just over the ear, and the ear cups also flex and rotate to further help with the fit.
My only qualm with the HD 668B is quality control, sadly my first pair had a very loud resonance on the left driver from around 230-250hrz. I simply returned that one and repurchased another pair from amazon. Thus far I haven't had any problems with the replacement.
On the plus side, the pads are also removable and easy to swap out! I've yet to change mine out, but doing so does offer changes to the overall sound, so for this review I'm using the stock pads.
I find the stock pads to be plenty comfortable, even in the heat and humidity that's common here in the south eastern United States. Being semi open, the headphones do block out some central to higher frequency noise, things like fans and traffic. However you can still hear people speaking, vehicles and the rumble of heavy to light machinery. I've walked around my house while cleaning, or working with no issues. I've also spent some time at the gym with them, and while the sweat from the pads was problematic, the lack of noise was not. I was able to focus on my music, while still having enough audible awareness of those around me.
The overall tone of the Superlux HD668B is Cold and Dry, I find it's presentation to be very Bright and the overall sound signature is a fun neutral. Measurements show that it has a slight v shape to it's frequency response.
I really love the bass of the HD 668B because it gives a wonderful speed and texture to a variety of drums. It even stays true to the power of an electric bass and the warmth of a stand up bass. My favorite moment with them, was finally getting to really HEAR the bass line in Metallica's The Shortest Straw, in addition to some intimate fret action added into one of my favorite bass solo's. Synth Sub bass lines are the only draw back to the HD668B bass presentation in my opinion. I enjoy the extra speed and hardness that the HD668B has to it's bass response.
The mids are very dry, however out of my HM 601 I found a wonderful timbre to many brass wood winds. Trumpets, the sax and even flutes all had a very life like presentation, trumpets maintained a metallic edge without sounding tinny. The Alto and Tenure Sax both had excellent body and bite. The bright presentation of the HD668B also presented the quick breath taken in-between each note. It is problematic with stringed instruments. Heavy Metal riffs had a nice crunch, but not real bite to them. Acoustic guitars, while having great timbre in the lower notes, had a very uneven sound overall and the same can be said for almost all stringed instruments. The harmonics of many of those instruments were lost in the overall presentation of the HD 668B.
Top end clarity is another pleasurable quality of the HD 668B, high hats, cymbals and the brightest guitar solos all have a wonderful sense of clarity and air. While some may find the treble to be too hot, or too bright, I really do like the shimmer that the HD668B brings, really makes you feel like you're walking on air.
Sound stage presentation is very wide, but lacks some depth. Left, right and center separation are excellent and though it lacks depth, the Superlux HD 668B holds you more or less equidistant from each instrument. On tracks with a very strong sense of depth it is audible, but it is by no means top of the line.
It's lack of depth is often overshadowed by it's amazing mirco detail or transparency, it's a headphone that will certainly add a sense of atmosphere and ambiance to your music. An let you really hear EVERYTHING. With the Superlux HD668B the devil, is certainly in the details! Good or bad, the Superlux HD 668B brings detail, if it's captured, chances are you'll hear it. This is also true of the equipment that you pair the HD 668B to, my HM 601s warmth helped to improve the tone of the HD668B, it softened a very stiff bass, and helped balance out the low to central mids.
In conclusion, the HD 668B is an incredibly transparent and fast headphone. While it's a tad drier than neutral, it pairs very well with a lot of entry level source and amplifiers, so chances are you'll probably not notice a lot of what I have, and best of all it's $40!!! So not only is it a total steal for this level of transparency, but it's also a fun headphone to own! There are so many ways that you make little adjustments to how the HD 668B sounds, from the cable you use, to the pads, to your source, to your amp, and if you own tubes I'd imagine it would be a blast to listen to tubes with! All in all, I highly recommend the Superlux HD 668B.
For a more in depth review, and a song by song break down with comparisons to other headphones, check out the in depth review here at Headfi.com
Sound
For the purpose of this review, I paired the HD 668B with my Hifiman HM 601.
I really love the bass of the HD 668B because it gives a wonderful speed and texture to a variety of drums. It even stays true to the power of an electric bass and the warmth of a stand up bass. My favorite moment with them, was finally getting to really HEAR the bass line in Metallica's The Shortest Straw, in addition to some intimate fret action added into one of my favorite bass solo's. Synth Sub bass lines are the only draw back to the HD668B bass presentation in my opinion. I enjoy the extra speed and hardness that the HD668B has to it's bass response.
The mids are very dry, however out of my HM 601 I found a wonderful timbre to many brass wood winds. Trumpets, the sax and even flutes all had a very life like presentation, trumpets maintained a metallic edge without sounding tinny. The Alto and Tenure Sax both had excellent body and bite. The bright presentation of the HD668B also presented the quick breath taken in-between each note. It is problematic with stringed instruments. Heavy Metal riffs had a nice crunch, but not real bite to them. Acoustic guitars, while having great timbre in the lower notes, had a very uneven sound overall and the same can be said for almost all stringed instruments. The harmonics of many of those instruments were lost in the overall presentation of the HD 668B.
Top end clarity is another pleasurable quality of the HD 668B, high hats, cymbals and the brightest guitar solos all have a wonderful sense of clarity and air. While some may find the treble to be too hot, or too bright, I really do like the shimmer that the HD668B brings, really makes you feel like you're walking on air.
Sound stage presentation is very wide, but lacks some depth. Left, right and center separation are excellent and though it lacks depth, the Superlux HD 668B holds you more or less equidistant from each instrument. On tracks with a very strong sense of depth it is audible, but it is by no means top of the line.
It's lack of depth is often overshadowed by it's amazing mirco detail or transparency, it's a headphone that will certainly add a sense of atmosphere and ambiance to your music. An let you really hear EVERYTHING. With the Superlux HD668B the devil, is certainly in the details! Good or bad, the Superlux HD 668B brings detail, if it's captured, chances are you'll hear it. This is also true of the equipment that you pair the HD 668B to, my HM 601s warmth helped to improve the tone of the HD668B, it softened a very stiff bass, and helped balance out the low to central mids.
In conclusion, the HD 668B is an incredibly transparent and fast headphone. While it's a tad drier than neutral, it pairs very well with a lot of entry level source and amplifiers, so chances are you'll probably not notice a lot of what I have, and best of all it's $40!!! So not only is it a total steal for this level of transparency, but it's also a fun headphone to own! There are so many ways that you make little adjustments to how the HD 668B sounds, from the cable you use, to the pads, to your source, to your amp, and if you own tubes I'd imagine it would be a blast to listen to tubes with! All in all, I highly recommend the Superlux HD 668B.
For a more in depth review, and a song by song break down with comparisons to other headphones, check out the in depth review here at Headfi.com