Superlux HD668B Headphones Review

By Julian Duque

Manufacturer: Goan-Fann Co., Ltd. dba Superlux
Product Name: Superlux HD668B Dynamic Semi-Open Headphones
Model Number: HD-668B
EAN: 4710423849747
Price As Tested: $37.95 (Amazon | Newegg)

Full Disclosure: The product sample used in this article has been self-supplied.

Superlux is a Taiwanese manufacturer of audio components that targets the “affordable market”. Their headphones have slowly entered the market during the past years and they have made quiet a hype in various enthusiast forums and gaming communities. At first, we were quite skeptical about the relatively unknown company as it is the first time we ever heard from them, and at such a low price, the Superlux HD 668B Headphones are the most affordable set of headphones that Benchmark Reviews has ever taken a close look at.

But it was this skepticism that along with our curiosity really set eyes and ears into these headphones. In this review we really wanted to uncover what the Superlux HD668B Headphones had to offer, and evaluate if they are capable enough to provide an enjoyable sound experience. To our surprise they have re-defined our concept of value headphones as they breezed through our tests.

A first glance revealed what seemed as the evil twin of the Audio Technica ATH-700X thanks to the peculiar headband design that features the “self adjusting wing support”. In contrast, a look at the spec sheet found on the back of the packaging in which the Superlux 668B Headphones come reveal a completely different product:

• Acoustic Design: Semi Open
• Frequency Response: 10-30,000 Hz
• Sensitivity: 98dB SPL, 1mW
• Maximum Power: 300mW
• Voice Coil / Impedance: 56 Ohms
• Weight (without cable): 222 g / 7.8 oz
• Cable: Detachable 1M/3M (please see page 2 for more details)
• Measured Headband Pressure: 3.45 N (After 3 Weeks of Constant Use: 3.19 N)

In this page we will take a glance at the style and looks of the Superlux 668B Headphones

The first surprise that came to our attention were the accessories, that before opening the package we thought would be non-existent at this price point. Included within the package are a 1M and a 3M straight gold coated cables that scream quality and can be inter-Connected to form a 4M cable. Also included, are a cable clip to mount aftermarket cables directly to the headphones and a 3.5/6.3 gold coated plug adapter. The icing on the cake is the soft carrying pouch that is more than large enough to accommodate the Superlux HD668B Headphones and the included accessories.

Aesthetically, the Superlux 668B Headphones seem very subtle, with the exception of the auto-adjustable wings. They are probably not the most stylish headphones we have ever reviewed, but they look good enough to be acknowledged. Just by holding them, they do not feel like something of this price point.

All around you find a matte black that hides the plastic body, which features a very smooth and appealing form, lacking the aggressive look of gaming headsets . Both the ear-pads and headband wings are made of synthetic leather, which is really comfortable to the touch. At first I found the ear-pads to be lacking comfort, however they can be easily swapped. The stitching is not excellent but it is more than sufficient to not give any concerns.

Concerning build quality, our first major observation came across the male cable termination that comes out of the left ear cup. It is nice that they allow for other cables to be used with the headphones but in the long term it feels like the cable might come out of the vessel if you are constantly unplugging or straining it.

Another thing to note is that during the first week of use the headband was a bit too stiff for my taste, but after some usage they start to give out and become more pleasant and adjustable. As uncomfortable as they may seem, they did not produce any fatigue in our long periods of testing while still maintaining a reasonable amount of clamping force to stay in place. Because the Superlux HD668B Headphones are so light, they can be used for a very long time without causing any strains, however don’t expect them to be as comfortable as headsets that are three times their price.

The Superlux HD668B Headphones offer a somewhat professional look that is not impressive until you reveal their price. The exterior does reveal some key features of what we might expect once we test them; being semi-open they will not provide the same isolation as closed headphones, however open headphones provide a really open and satisfying sound. The build quality is far from superior from other headphones at this price point, however I wouldn’t go in a rage with these.

Headphones are a very personal choice to many people due to the variety of music styles and sound taste that each person encounters satisfying. In this section we will only discuss how the Superlux HD668B Headphones perform in a gaming environment, if you want to see the section regarding a more broad test we recommend you skip to the next page.

To get an enjoyable experience out of the Superlux HD668B Headphones you do not need to have a very expensive setup or the most expensive DAC available in the market. You could easily power the Superlux HD668B Headphones from your on-board audio or a portable device such as your phone or iPod, but for our gaming test we decided to use both an Audioengine D1 USB DAC and the on-board audio from our Gigabyte Z87N motherboard which has a Realtek AC892 audio chipset.

Here is a list of the games that we tested with these headphones:

• Battlefield 4
• Skyrim – The Elder Scrolls
• Dead Space 3
• Hawken
• Arma 3

So here came the moment of truth, did the Taiwanese Superlux HD668B Headphones managed to impress us? The answer is yes. As we anticipated, the semi-open acoustic design really allow the drivers to create a great sense of space, even without using an external DAC. While playing Hawken and Battlefield 4 it was really easy to spot explosions and enemies. We did see a slight improvement by using the Audioengine D1 DAC as it pushed the 50 mm drivers to deliver a more accurate sound quality, specially in the low frequency range were all the explosions and intergalactic robot fighting occurs. The Superlux HD668B Headphones deliver a very tight bass, however it is a bit aggressive but not enough to disturb the rest of the spectrum.

One cool feature about Dead Space 3 is the implementation of a very real sound environment. The ship through which the main story takes place creaks and gives the player an even more eerie experience, a setting that is almost perfect to test the capabilities of the Superlux 668B Headphones.Starting with vocals in the game, the Superlux 668B Headphones bring the mids right were they belong. Although the vocals are not heavy like in premium headphones, they lie right in place to deliver a satisfying voice without emphasizing sibilance. Other environment noises are also delivered in a effortless and beautiful manner, something you would expect out of headphones priced way above our test subject.

So far, these headphones have showed that it is possible to deliver a good gaming experience for less than $50. It could be argued that they perform better than some of the other “premium” options.

Even though they are the cheapest set of headphones we have ever reviewed, the Superlux HD668B Headphones deserve to go through the same tests as other headphones. We performed this review with the help of AudioCheck.net’s sound test to check for frequency response, sound quality, driver matching, and binaural signal. We also used a mixed music playlist to evaluate sound quality.

To accurately test using AudioCheck.net it is recommended that all audio samples are downloaded and not played online, so as to avoid any distortion caused by the compression of online media. Our test systems are completely different to cover how the Superlux HD 668B Headphones perform in each platform. We also created a music playlist that includes more than 36 hours of mixed genres including Metal, Dance, Classical and Soft Rock.

• Personal Computer (using an Audioengine D1 USB – DAC )
• Nokia Lumia 521 Phone
• IPod Nano 6

• Led Zeppellin – Led Zepellin IV
• Nicolas Jaar – Darkside
• Claude Debussy – L’enfant Prodigue
• Soda Stereo – Cancion Animal

Frequency and Response and Dynamic Range: One prominent feature from the Superlux 668B Headphones are the big 50 mm drivers that are gracefully placed in their semi-open design. These two are the ones to blame for the great clarity and depth of these headphones, and for the great performance in the low and mid-range. However, when we first got these headphones, there seemed to be lots of disturbances in the highs. These disturbances can be fixed with the right EQ, on our iPod Nano this issue was easily fixed by using the included EQ option “Treble Reducer”.

On our test using AudioCheck.net we found that at about 6 kHz the treble would start to become a bit disturbing. We found that they responded right until about 20 kHz, were we met our roadblock. On the lows we found a pretty stable and linear response right until about 270 Hz were it dropped slightly. Overall very linear performance except in the highs, however this was fixed by using an EQ. For this price it is really hard to find similar performance. Concerning the impedance, the Superlux 668B Headphones will play just fine on most portable devices, however they might sound slightly better on a dedicated sound card or DAC.

Binaural Testing: Binaural testing is the ability to fully recognize the location in space by using the noise produced by an object. It is usually a good indicator to isolate a great pair of headphones from the rest. There are many ways to test this, however we decided to use a soundtrack that takes great advantage of binaural recording. By listening to Claude Debussy’s L’enfant Prodigue and closing our eyes we could clearly identify were all of the objects or players were located in the recording. Just for the sake of testing it, when we plugged them into our DAC we could almost identify the distance from each artist in L’enfant Prodigue, as if almost we were in the same room. Binaural testing, definitely not a problem for our underestimated test subject.

Sound Quality: The most astonishing feature from the Superlux 668B headphones is their sound clarity. It is a complete pleasure to just sit down and listen to Nicolas Jaar;s low relaxing beats, or if you are of more classical taste, we could almost hear a distant cough in our L’enfant Prodigue studio recording. Vocals are astonishing, they might sound a bit too bright if not EQed, but when fixed both Led Zeppelin and Soda Stereo sounded almost like I was using my Audio Technica ATH-A900X with a more vibrant noise. For the price, I do not think you can find a better Sound Quality, the Superlux HD668B Headphones have performed really well as budget headphones.

The Superlux HD668B Headphones live up to the standard of headphones twice their price. They might not have the strongest construction, nor a trusty brand label but if Superlux keeps delivering products like this we are surely going to be paying close attention. Of course, if compared to premium headphones we did find some mistakes. The design itself is not the most comfortable, the body is fully plastic but if that means having a better sound experience I would not mind it at all at this price point. The Superlux HD668B Headphones are probably meant to be kept at home or at the office, as probably any abrupt fall might send them to headphone heaven.

Regarding the sound experience, we did find some small disturbances in the highs with a very abrupt treble, however it was easily fixed with the right EQ. The mid and the lows were truly beautiful, they just sounded right and accurate, something we did not expect at all. If you are planning on buying a cheap set of headphones as a gift or for your office we really recommend you take a look at the Superlux HD668B Headphones.

The Superlux HD 668B Headphones have truly raised the bar on the budget category of headphones. Unless you are trying to find a more stylish option, I really really suggest you look into what Superlux has to offer. If you are wondering why, I strongly suggest you read the rest of the article as how they perform can not be summarized in a few sentences.

As I mentioned before, the appearance is probably the thing the Superlux HD668B Headphones lack the most. They are probably notmy first option when going out to run or to travel, but if you are willing to just keep them at the office or at home they will surely give you a smile.

When thinking about construction I have to constantly keep reminding myself that they sell for only $37.95 (Amazon | Newegg). If you treat them with respect, and don’t go about using them as a weapon they will surely last long. One important thing to note is the plug interface that to us seemed vulnerable if you were to pull on it hard.

The Superlux HD 668B Headphones might not be popular among music producers, or people looking for the uttermost sound quality. But for everyday users that are just looking for a “good-enough” option, they are more than functional. You could easily plug a ModMic and have a great gaming headset.

I want to end this review by simply apologizing as I never thought I could find such a wonderful sound experience for less than $50. I completely underestimated these headphones, as they are worth every dollar if you are willing to live with the very few sacrifices.

+ Great Mid and Lows
+ Bass is solid and tight
+ Comfortable to use for long periods of gaming
+ Detachable cable interface
+ Comes with a 1M and a 3M cable
+ Great sound experience
+ Interchangeable ear pads

– Abrupt treble
– Plastic body
– Self Adjusting Wings are stiff

• Performance: 9.00
• Appearance: 7.75
• Construction: 7.5
• Functionality: 8.5
• Value: 9.75

COMMENT QUESTION: What other “value” headphones would you like us to review?