The Superlux HD 681 are very similar to the Superlux HD 668B in shape and sound. They're a bit more comfortable, thanks to the different headband design that's not as tight on the head. They also sound better than many pricier headphones, but they're not very versatile. They're cumbersome, don't block a lot of noise, and leak quite a bit, meaning you're best off using them in isolation.
The Superlux HD 681 are a good budget option for neutral listening. They have slightly more extended bass than the Superlux HD 668 and deliver a satisfying audio reproduction that caters well to instruments and vocals. They have a relatively flat mid-range but tend to sound slightly sharp because of the bump in the high-mid/low-treble, especially with tracks that are already a little bright. Sadly, their soundstage isn't as immersive as some of the other fully open-back headphones. Overall, the sound quality is good for both casual and neutral listeners.
The Superlux HD 681 are poor for commuting. They're not for this use, as they don't block a lot of ambient noise, aren't portable, and don't have the most durable build quality.
The Superlux HD 681 aren't for sports. They're bulky and impractical to use outdoors. They're a bit more comfortable than the Superlux HD 668B, but they're less stable and won't be ideal to use while doing physical activities. They don't have any controls, which makes controlling your music source while exercising a bit more of a hassle.
The Superlux HD 681 are subpar for office use. They let a lot of noise seep into your audio and leak a lot, which might be distracting to your colleagues.
The Superlux HD 681 are wired headphones, so you can't use them for wireless gaming.
See our recommendations for the best headphones under $50, the best budget wireless headphones, and the best wired headphones.
The Superlux HD 681 are better for neutral sound than the Samson SR850. They have a similar semi-open design, but the Superlux have a much more neutral sound profile, which some may prefer. They're also much more comfortable and breathable. However, the Samson have a significantly better build quality.
The Superlux HD 668B and the Superlux HD 681 are both very good headphones if you like a neutral sound, but the HD 681 have a slight edge. While they both can sound quite harsh and sharp, the HD 668B also lack thump and rumble, on top of sounding a bit muddier. The HD 681 are also much more comfortable.
While the Superlux HD 681 and the Superlux HD 681 EVO are similarly performing headphones, the HD 681 are better for neutral listening. They have a more balanced sound and a better passive soundstage. However, the HD 681 EVO have slightly better build quality, and they're a bit more stable on your head.
The Philips SHP9500 are somewhat better for neutral sound than the Superlux HD 681. The Philips are more comfortable, more breathable open-back headphones. Their passive soundstage is perceived as much more open and spacious as well. On the other hand, the Superlux have a semi-open design. They leak less sound and have a more accurate bass response, so mixes have more thump and rumble.
The Superlux HD 681 and the AKG K240 MKII are similarly designed headphones, but the Superlux have an overall better-balanced sound profile. The Superlux produce much deeper bass with less clutter in the mid-range but sound a bit harsh and even piercing in the higher frequencies. The AKG have a smoother treble and feel better built.
The Superlux HD 681 are better critical listening headphones than the Audio-Technica ATH-M20x. The Superlux semi-open headphones are more comfortable and offer great audio quality, especially for their affordable price. Their design makes them more open-sounding, although their build quality is pretty cheap and fragile. On the other hand, the Audio-Technica will be better headphones to bring on the go since they are closed-backs, which means they block a bit of ambient noise and don’t leak as much as the Superlux.
The AKG K712 PRO and the Superlux HD 681 are both great audiophile headphones if you like a neutral sound. They have fairly similar profiles, though there are a few differences. The Superlux get quite a bit more bass, and they also sound brighter in the treble range, which gives them a slightly more excited sound profile. They're also less comfortable than the AKG and feel a lot more cheaply made.
The Superlux HD 681 and the Beats Solo Pro Wireless are for different uses. The Superlux are designed with audiophiles in mind. They have a semi-open enclosure, which helps improve their passive soundstage performance, a neutral and accurate sound profile, are more comfortable, and their passive soundstage performance is better. However, the Beats are more suitable for casual use. They have a wireless design, are better-built, and have an ANC system that can out a great amount of ambient noise around you. They also have an H1 chip, so you can seamlessly pair them with your Apple devices.
The Superlux HD 681 look very similar to the Superlux HD 668B. They have practically the same ear cups but a different headband design, making them look more like the AKG K240 MKII. The color scheme is pretty bland, but this model stands out a bit thanks to the red accents on the ear cups and headband. Unfortunately, their plasticky build quality makes them look cheap and not durable.
The Superlux HD 681 are more comfortable than the Superlux HD 668B. They're just as lightweight and have a better headband design that doesn't feel as tight on the head and extends a bit further than the Superlux HD 668B. They also have large ear cups that fit well around most listeners' ears. Unfortunately, the ear cup padding feels a bit stiff and may cause a bit of uneven pressure. It's not particularly uncomfortable, but it's noticeable after wearing them for a while.
The Superlux HD 681, like the Superlux HD 668B, are cheaply made and plasticky. They feel like a budget version of the AKG K240, which shows in their build quality. They have a plastic design with no metal parts, and all the materials used in their build quality feel slightly low grade. They won't break if they accidentally fall once or twice, but they don't feel like durable headphones.
The Superlux HD 681 aren't as tight on the head as the Superlux HD 668B and are slightly less stable. They won't be the best for sports since they have big ear cups that sway during physical activity, but they don't move much during casual listening sessions. Unfortunately, this model doesn't have a detachable cable, so the headphones will get yanked off your head if the cable gets hooked by something.
These headphones have good consistency performance. The bass range performance is very consistent across human subjects, except for the one subject who wears glasses, as he gets 3dB less bass than others at 20Hz. The treble range consistency is also very good, especially below 10KHz.
These headphones have very good mid-range performance. Low-mid and mid are virtually flat, but under our target by about 2dB. This pushes vocals/leads slightly to the back of the mix, giving more emphasis to the bass and treble ranges. High-mid shows a small tilt favoring higher frequencies, but the effect will be very subtle.
These headphones have decent treble range performance. Low-treble is well-balanced but slightly inconsistent. Treble has a 10dB bump between 7KHz and 12KHz, making the sound of these headphones noticeably sharp and sibilant.
The Superlux HD 681 have poor isolation performance. Due to the semi-open back, they don't isolate at all in the bass and mid ranges. In the treble range, they reduce the outside noise by about 20dB, which is decent.
These headphones don't have any compatible app.
Since these headphones have a wired connection, there's negligible latency.