Superlux HD 681 Review

by Alex.   Last Updated On September 15th, 2022.
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Wired semi-open headphones are something of a novelty. They are right in-between open-back and closed-back headphones and are the go-to choice for anyone that doesn’t want to decide which way the wind blows.

Many close-minded closed-back headphone extremists (who dwelled too much on the differences between open-back and closed-backs) would argue that these semi-open headphones are just open-back headphones with a new coat of paint, and considering the poor noise isolation and sound leakage capabilities, they might as well be. However, it’s unfair to judge these devices without taking the plunge and checking out how they sound.

Fortunately, I’ve found just the right pair of semi-open headphones for that purpose: introducing the Superlux HD 681 Dynamic Semi-Open Headphones, they are the perfect semi-open contender for beginners to get into the wondrous world of semi-open headphones. So, with that said, I’m going to review this pair, and see how it’s the overall design and sound quality fare up. After that, I’ll also consider some pros and cons and let you know if these Superlux HD 681 would open up my eyes (or ears) to the potential of open-back headphones.

Table of Contents
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Specs

Drivers: 50mm Neodymium Drivers Circumaural

Type: Dynamic Semi-Open

Frequency Range: 10Hz-30kHz

Impedance: 32Ω

Weight: 0.5lbs

Wired Connectivity Options: Gold Plated ⅛” TRS (3.5mm) Jack

Design

Looks and Build Quality

Although many would consider this semi-open Superlux HD681 to be the “gateway headphones” to the more natural-sounding open-back headphones the design and build quality of this bad boy leaves a lot to be desired.

Right off the bat, I’m gonna say it: these headphones look cheap. Everything is made out of plastic and no matter the red accents and the cool-looking adjustable knobs on the headband, this pair of headphones are not what you would want to impress anybody with.

The earcups (on these bootleg AKG K240 MkIIs) are large enough to fit most ears. Nonetheless, the cushion covers look very bland and the stitching around the earpads is very ugly, and the manufacturer should fire Leatherface for doing a very horrible job. However, on a lighter note, the elastic headband slides up and down very easily and will comfortably fit any head that chooses to adorn these.

In regards to the build quality of these headphones, all I have to say is that Superlux, (or whoever, the manufacturer is) did a pretty lousy job by adding all plastic components to the design. Although the headphones are very flexible and feel very loose and limp, the plasticky material is not very durable. Fortunately, it can hold itself together for a couple of drop tests without major damage.

Comfort and Portability

Surprisingly, these headphones are very comfortable to wear for long periods. This is where the lightweight plastic body and elastic headband show their value. The ear cups are large enough to cover most average ears and because of the auto-adjustable headband, the headphones do not tend to wrap too tightly around the ears. However, one complaint is the padding on the earcups, many complain that the cushioning on the earpads is not as soft as they like to be and it feels a little awkward when the ears aren’t fully covered.

In terms of portability, these pair of headphones happen to take a significant blow. The earcups cannot be folded, even though the elastic headband allows them to flex and twist easily. Wearing them around your neck is very uncomfortable as the large earcups will prevent you from turning your neck. On top of that, the headphones aren’t very stable and will easily fall off when running or stretching into some “down dogs.”

There’s a pouch that will protect the headphones from scratches. However, they aren’t the best of quality and won’t save your headphones from accidental drops or impacts.

Overall, these wired semi-open headphones are only suited for studio work and indoor entertainment. So if you are looking for a pair of good over-ear headphones for working out, best to look elsewhere.

Controls and I/O

Like many wired open-back studio headphones like the Philips Fidelio X2HR, the control and I/O options on these headphones are almost nonexistent. There are no buttons or volume rockers on the headphones themselves, so if you need to change the volume you’ll have to use a headphone amplifier or the volume controls on the source device.

In terms of I/O, these semi-open headphones use a 3.5mm detachable headphone cable. There are an 8ft long cable included out of the box along with a ⅛” to ¼” TRS adapter. Unfortunately, there are no USB interfaces or in-built microphones, so if you were hoping to use these headphones for gaming or answering calls, I recommend getting a separate microphone like the OneOdio FM1 or opting for a pair of dedicated audiophile gaming headphones.

Sound

Bass, Mids, and Treble

The redeeming quality of these Superlux HD 681 semi-open headphones is the well-balanced and accurate sound reproduction. The bass reproduction is very impressive and there is no distortion or unwarranted modifications. The mids are also very impressive and reproduce accurately with minimal distortion. The highs can be a bit tricky, especially at the upper end but all things considered, these pairs of headphones do a tremendous job of reproducing neutral sound, making them perfect for beginner recording studios.

Noise Isolation and Sound Leakage

Unfortunately, the noise isolation and sound leakage capabilities of these Superlux HD 681’s are very poor, almost on par with open-back headphones. (which are notoriously bad at eliminating background noise.) So if you are ever using these for studio work, make sure to soundproof your recording studio adequately.

What’s In The Box?

  • Superlux HD 681 Wired Semi-Open Headphones
  • Carrying pouch
  • 8ft long 3.5mm (⅛” TRS) headphone cord
  • ⅛” to ¼” TRS screw-on adapter

What We Like

  • Relatively exceptional sound quality
  • Very attractive price tag
  • Somewhat comfortable design with elastic headband

Know Before Buying

  • Looks and feels cheap
  • Bulky and awkward to carry around
  • No in-built microphone
  • Poor noise isolation and sound leakage

Conclusion

The Superlux HD 681 is not perfect by any means. It’s got a lot of quirks that prevent it from being a solid all-rounded pair of headphones. Due to its bulky design and semi-open earpads, this pair of headphones is not ideal for working out, traveling, or eliminating noise. However, one use-case where it outshines the competition is when doing studio work, the neutral audio reproduction performance on these bad boys are top-notch and they are worth a buy because of their very attractive price tag.