The AKG K240 MKII are semi-open, critical listening headphones with an above-average sound. They're comfortable to wear and deliver an immersive audio reproduction. Unfortunately, they're not the most versatile headphones. They perform poorly in loud environments and their bulky, cumbersome build is a bit unstable on the head.
The K240 MKII are critical listening headphones that are not versatile enough for other use cases. They're comfortable and deliver a good sound. However, they can't practically be used outdoors or in loud environments. They're also bulky headphones to carry around on your person, and will easily fall off your head if used while doing any sort of exercise.
The K240 MKII are built to be neutral listening headphones that deliver an immersive audio reproduction. They have a great soundstage for a semi-open design and reproduce instruments and vocals well enough to please most neutral listners. However, they lack a bit of bass and do not sound as crisp and clean as some of the other models in AKG K series
Not designed for commuting. They have semi-open ear cups that let the ambient noise of your surroundings seep into your audio. Hence in loud environments like a bus or train, they will not perform well.
Not meant for sports. They're big and bulky and difficult to carry around on your person. They're also quite unstable and will quickly fall off your head if used while running.
Subpar for office use. They leak a lot, which means people will be able to hear what you're listening to. They also don't block enough noise for lively offices.
The K240 MKII have a similar design to the rest of the K series. They keep the familiar old-school headband and circular ear cups, but the materials used in this build do not feel as premium as those used on the K702 and K712 PRO. They also have a pretty bland color scheme, but the understated look may work for some. Overall these are decent looking headphones, but they feel a bit cheap.
The K240 MKII have a pretty comfortable design. They're quite lightweight for their size and they're not too tight on the the head. Also the ear cups are sufficiently well padded that they won't cause any soreness during long listening sessions. However, the circular shape and size of the ear cups do not always fit well around larger ears. Also, the lack of padding on the headband slightly decreases their comfort level but isn't particularly noticeable once you have the headphones on.
The K240 MKII are not portable headphones. They have a bulky design that doesn't fold or have ear cups that lay flat to take less space. They will be a hassle to carry around on your person and will only fit into larger bags. They also don't come with a case so keeping them in your bag with other items might not be the best way to transport them.
Decent build quality. The MKII have a similar design to the AKG K701 and K702. They have moderately dense circular ear cups that can survive a couple of drops without being damaged. However, like the rest of the K-series, the headband has a lot of moving parts that will deteriorate over time with regular wear and tear.
These headphones are not designed to provide a stable fit during physical activity. The slack headband isn't too tight on the head, which is good for comfort but unfortunately, makes the fit unstable in most situations. They're a little bulky and cumbersome and will fall if you tilt your head too far back during casual listening sessions. Therefore they won't be good headphones to exercise with. The cable is detachable but locks into the ear cups, so it will still yank the headphones off your head if hooked on something.
Poor leakage. Although these headphones are marketed as semi-open, their isolation is on par with fully open headphones. Therefore, they provide no isolation up to 2KHz, and the isolation they achieve above 2KHz is well below average.
Poor leakage. These headphones leak a considerable amount, due to the semi-open-back design. The majority of the leakage is between 500Hz and 10KHz which is a broad range. The level of the leakage is also quite high.
No compatible app.
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.