Koss PortaPro vs AKG K391 NC

The drivers may be small and thin, but there is good bass presence.. The mid-range may not be the most detailed, but there is a smoothness to it that gives the sound a warm and pleasing quality. There is a slight roll-off to the high frequencies yet detail and extension is still good . Overall, these headphones can give a fun listening experience that can work well with all genres of music.

Koss provides a lifetime warranty for these headphones.

The ear cups can be folded into the headband. This further reduces its already slim design into something that is much more compact. When folded down, these headphones can easily fit in small bags.

The headband can easily be adjusted to fit a user's head. The assembly features sliding metal pieces which can easily be set to fit small to large heads.

Aside from headband adjustment, users can also adjust the clamping force of the ear cups using the Comfort Zone system. This changes how secure the ear cups attach to the headband, which results in either a loose or tight clamp.

These are eye-catching headphones because of their retro design. The unusual shape of the driver case and the blue accents definitely make these look unique.

These headphones may look thin and flimsy, but are actually much more durable than their look suggests. The headband is made out of metal and can take some flex without snapping. The plastics used also exude a quality feel.

When used on the go, these headphones get extra protection from the included carrying pouch. This pouch looks simple and is made out of pleather, which should protect these headphones from scratches.

The accessories included are all very useful. You get two 3.5mm headphone cables, a USB charging cable, silicone ear tips, a travel pouch and an airplane adapter.

You can easily replace the 3.5mm cable should it get damaged. You can detach the 3.5mm cable from the control module which is very convenient. Other noise cancelling modules have fixed cables, so you’ll have to replace the headphones should the cable get damaged.

You can take calls with these headphones on. A microphone is integrated into the remote which makes answering calls fast and convenient.

A good amount of noise will be blocked from mixing in with your music. Loud, low-pitched sounds may still be clearly heard though

You aren’t likely to have issues using these on the go. Most active noise cancelling in-ear headphones have large control modules, while the K391NC has a fairly compact and light module. You can easily use these headphones while walking and comfortably enjoy active noise cancelling with your music.

The highs are quite detailed, yet do not get harsh. The mids are slightly forward, so vocals and instruments can easily be heard. The bass is not very powerful but is tight, so you’ll get decent punch from your music.