Fairly new on the headphones scene, the Koss Pro4S just landed on my desk and looks to be aching for a review. At $150, it's competing with the likes of the Audio Technica M40x and M50x, and even the AKG K553. But how does it stack up and is it worth the price?

The Pro4S comes in a no­nonsense package, with semi­hard nylon case and a removable 4.5 ft coiled cable. There's also a 1/4" stereo adapter plug in the box. The headphone feels solid in your hands, and it has an input jack on either earcup, allowing you to use the cable on the left or the right side. You can also link multiple headset through the unused port, "daisy­chaining" as Koss puts it on their website. This last feature strikes us as pretty badass, but we're also stoked when we get to choose which side our headphone cable is placed on. The headband and extenders are made of a thin, flexible aluminum band, and the earcups supposedly have a fair bit of metal in them, too. The band is padded with a mesh­layered pleather material, and the earcups are a softer iteration of that luscious pleather.

The cups swivel just a little bit past 90 degrees on a hinge that also allows the cups to bend in toward the headband. The coiled cable is robust, and gives me a warm fuzzy feeling inside.

Overall, the build quality is on par with the M40x and M50x, and with the K553 Pro. Although, this headphone from Koss feels a little more pliable and a little more ergonomic (thanks to those D­shaped earcups), but it's the same solid impression you'll get from almost any other headphone in this price range. While it doesn't come with as many cables as the Audio Technica options, the choice between connecting to the left or the right more than makes up for it. At least to me.

The sound of the Koss Pro4S is another story, standing on its own little pedestal. The sound is spacious and articulate, with just a slight twinge of bass. Not too much, just a little less than the M50x... maybe. Sometimes I feel like it's there and other times I feel like it's not. It may not be particularly embellished, but it may be due to the driver in the Pro4S.

Mids and highs are accurate. Nothing is out of place, underplayed, or grating on your ears. The separation, for a closed back model, is also pretty good ­ definitely putting them in the same sonic pantheon as those models from Audio Technica and AKG. However, the overall sound of the Koss seems less pinched and less constrained than that of the M40x and M50x. It seems just a tad bit more dynamic than the K553, with some heartfelt bass and treble that does just enough to get you feeling, but doesn't necessarily detract from the overall sound.

It's hard to agree that these are professional studio headphones. Maybe they are and we're just imagining the slight coloration at the low and high end of the frequency range. However, if that's the case, these must be the best studio models we've ever auditioned. If our ears aren't playing tricks on us, though, then it's still a damn fine headphone, just not the most accurate.

Carroll Moore is a Tech lover and audiophile headphone enthusiast, photographer and writer for the likes of Audio46.