The Superlux HD 681 EVO are a slightly better-designed version of the HD 681. They sound about the same although the EVO has a bit more bass. They're also budget and affordable headphones for the quality of audio reproduction they deliver. Unfortunately, they don't have the best build quality. They feel cheap and flimsy, and the semi-open design means they won't be suitable for all environments.
The Superlux HD 681 EVO are a somewhat improved version of the HD 681 with a detachable cable. The headband design is slightly different but is still as comfortable HD 681 and better than the HD 668B. Unfortunately, they don't have the best build quality. They're flimsy, plasticky and feel a bit cheap. They also have a bulky design that's impractical and bit too cumbersome for sports or outdoor use. They won't be suitable to run with, they have no control scheme, and they're not portable.
The HD 681 EVO are decent-looking but plasticky headphones. They have a completely different ear cup design to the HD 681 and 668. They're still semi-open ear cups, but the vents are slightly hidden giving these headphones a more closed-back look. The headband strap is also a bit different but has the same fit and comfort level as the original HD 681. However, unlike the other Superlux headphones these come in two color schemes. An understated and glossy black finish and a more flashy white that will stand out but may not be for everyone. They're also a bit bulky and cumbersome to wear and use outdoors.
The Superlux HD 681 EVO have the same strap design as the HD 681 which makes them more comfortable than the HD 668B. They're a bit tighter on the head than the original 681, but the large ear cups and self-adjusting headband fits comfortably for most. They may get a little tiring during long listening sessions, but they're lightweight and come with additional softer pads that feel better on the skin thanks to the microfiber coating.
The HD 681 EVO like the HD 681 and HD 668B feel cheaply made and plasticky. They're budget headphones which show in their build quality. They're almost entirely made out of plastic that doesn't feel dense or durable. They won't break if you accidentally drop them once or twice, and they have a detachable cable that you can replace, but their overall build quality isn't particularly sturdy.
The HD 681 EVO are as tight on the head as the HD 668 but also have a detachable cable. This makes them moderately stable, especially under casual conditions. However, they're not designed or meant for sports. They will quickly fall if you use them while doing any physical activities and won't be good headphones to work out with or to take to the gym.
The Superlux HD 681 EVO are a good sounding pair of semi-open over-ear headphones. They have a deep and powerful bass, a balanced mid range, and a good treble. They also image well and have an average soundstage. However, their bass delivery can vary from person to person, their mid range is slightly recessed, and their treble could sound a bit too sharp on overly bright tracks.
Great bass range performance. Low-bass, which is responsible for rumble and thump is extended down to 10Hz. Additionally, both low-bass and bass are overemphasized by about 2.5dB, making these headphones slightly bass-heavy.
Good treble range performance. The narrow 5dB dip centered around 4KHz will have a small negative effect on detail and presence of vocals/leads. The peak around 10KHz could make S and T sounds a bit sharp and piercing on overly bright tracks.
Decent consistency. The HD HD 681 EVO shows good consistency in its treble range, with the maximum deviation of +/-3dB below 10KHz. In the bass range however, the 681 EVO is less consistent in its bass delivery across different humans, and could even be affected by wearing glasses..
Average harmonic distortion performance. The amount of harmonic distortion in the bass range is elevated, however humans are less sensitive to low frequency harmonic distortion. On the other hand, the peaks around 1.5KHz and 4KHz could have a negative effect on the treble of these headphones by making it sound a bit harsh and brittle.
The HD 681 EVO are not designed to block ambient noise. They have semi-open ear cups that create a more immersive soundstage but also leaks and lets noise seep into whatever you're listening to. This makes the HD 681 EVO not suitable for commuting or other loud environments although their isolation performance is a bit better than the HD 668B or the original 681. Also since they leak quite a bit they won't be ideal for use in quieter settings if you don't want to distract those around you.
Poor isolation. These headphones don't have active noise cancellation, and are also semi-open. Therefore, they don't isolate below 1KHz. Above that, they achieve about 24dB of isolation, which is about average.
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