Koss PortaPro vs Oppo PM-3

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.

Treble is quite detailed, but lacks a bit of sparkle on the highest frequencies as they are rolled off. The mids are just right, not too forward and not too rich. The bass has good presence and punch, but is not very powerful.

Its closed back design along with the fairly thick, leather-surfaced earpads are very effective at keeping the music in and the ambient noise out. This is very useful in tracking situations, and will also help you focus on the audio even when in a busy, noisy place.

The headband and ear cups have fairly thick padding to ease the pressure on the head. These are covered with leather material so they feel smooth.

A headphone amp is not required in order for these to pump up good volume and sound details, so these can work well off of portable devices. There is a noticeable improvement in sound quality and volume when used with a proper amp though.

A combination of high quality plastics and metal are used for these so there is minimal flex and rattles. The headphone joints and yoke also have smooth movement, which make these feel premium when held.

The cables can easily be detached, with 3.5mm jacks as ear cup connectors. This makes looking for new/replacement cables very easy.

Stock cable has an in-line microphone. Not only is this convenient for taking calls while listening to music, but the mic's sound quality is good, with voices sounding clear, full and with good volume.