A Sonic Stunner: The Koss SP330 On-Ear Headphone

This story originally appeared at InnerFidelity.com

Some introductory thoughts on Koss.
I have to admit significant mixed feelings about Koss. On the one hand, they've produced some truly excellent headphones in terms of value/dollar. The Porta-Pro (reviewed here), KSC-75 (and earlier variants), and ESP 950 headphones have had a strong following and fan base in the headphone hobby since day one. There's even a meme of sorts among enthusiasts giving advice to novices entering the fray, "Buy a set of Porta-Pros, then, if you can find something better, get it." Many experienced headphone enthusiasts still have one in the stable...I do.

On the other hand, Koss has many headphones that are pretty poor. My first headphone ever was a Koss Pro4AA back in the mid-70s. Unfortunately the current model is a mear shadow of it's former self, and the sound quality is atrocious in my opinion. I think they should cull the herd a bit.

Koss_SP330_Photo_StockPerformanceKoss as a brand also suffers from a remarkably old school vibe. Say the word Koss, and the first thing that comes to my mind is Radio Shack. Many of the headphones they carried were re-branded Koss models. These days, both companies suffer from tired brands.

A tired brand alone is enough to kill a company, but Koss has seen even worse troubles in the last five years. In 2010 Koss had to fire their VP Finance, Sue Sachdeva, who embezzled some $34 million from the company over the course of ten years. With only $40 million/year in gross sales Sachdeva's criminal behavior surely must have wasted the lion's share of profits.

Koss has also spent some $4.5 million on developing a wireless headphone system that appears to have had significant trouble, and are currently in court with the design firm that worked with Koss on the project.

For a very nice overview of Koss' current situation see this article.

All told, it seems to me Koss has had a very rough ride. Something has to go really right, really soon, or they may go the way of Blockbuster, Kodak, or Sears. Change, get relevant, or die. At this point I think Koss really needs to focus on what they have always done well: Make good performing, low-cost headphones.

The good news is that with the new SP330, they've done just that. I'll add that their new SP540 and Pro4A are decent performers as well, I'd say above average in their categories, but for me, the SP330 is outstanding.

Koss SP330 ($129)
The SP330 is a compact, sealed, on-ear headphone. The styling of the SP330 is simple and understated. Major parts are a soft-to-the-touch matte black plastic with chrome and brushed aluminum accents on the headband and earpieces. Earpads are protein leather over memory foam; the headband pad is black mesh fabric over memory foam.

Due to its very light weight, the SP330 is a very comfortable headphone, but I found because of its very compact size it does take a bit of fidgeting to get it properly adjusted to fit on my head. Caliper pressure may also need to be adjusted for best bass response. I found the headband extension arms can be gently bent to provide just the right amount.

Earpads rotate flat for storage and transport, but lack any folding mechanism to significantly reduce size. I've got mixed feelings about this: These are very compact headphones and could be made more so with a folding mechanism, but those mechanisms are also prone to failure.


Accessorization is a bit thin. The cable, at 54", is just about right for portable applications, but lacks a remote/mic for phone use. The carry case is a rectangular hard-side case, which is good, but Koss seems to be saving money by using the same case on many of their current models and just changing the internal molded insert for the various cans. This, unfortunately, means that the carry case is significantly larger than need be for these compact headphones.

In sum, I think the physical build of these cans is a mixed bag. I'd like to see them at $99, which might eventually happen, but at $129 they seem just a bit overpriced. Until you start listening...

Sound Quality
Stunning really, completely unexpected. This is really a terrific sounding headphone at the $129 price.

Overall, I'd characterize the SP330 as a neutral sounding headphone. Bass quality, punch, and extension is very good, but quite reliant on getting a good seal and proper position on the ears. Increasing caliper pressure by bending in the headband extensions goes a long way to achieving good bass response, as does just letting them warm up and settle into your ear shape. Bass to mid-range transition is excellent—no thickness or bloat in the low-mids at all.

The mid-range is wonderfully clear and even. Listening to mid-range elements at loud levels can often lead to a hard and shouty character, the SP330 seems to take it all in stride without breaking a sweat. Mid-range to treble transition is also excellent. Many headphones tend to fall off excessively above 1-2kHz, the SP330 remains very flat up to the mid-treble and as a result have a very present and close-up character. I very much get the feeling of row one seating with these cans. Want to hear the saliva on the sax reed? The Koss SP330 will do the trick.

The only area I have issue with is somewhere in the upper half of the treble. Sometimes very fast transients will take on a slight metallic "ting" sound, or overly pronounce cymbals. The resolution and transient response otherwise is wonderfully articulate and natural. For all of you who know my tastes, the SP330 is just a tad bright for me, but I think most would call it right down the middle with an excellent over-all balance.

I did spend a bit of time comparing the SP330 to comparably priced headphones. In comparison, the Onkyo ES-FC300 was a bit bass excessive and loose; the Philips Citiscape Downtown lacked the resolving power; and the Noontec Zoro HD sounded somewhat rolled-off. The SP330 has great sound quality relative to other ~$100, ear-pad, sealed headphones.

As an audiophile, I get pretty disappointed when a headphone nails styling and comfort, but falls flat with sound quality. The Koss SP330 is somewhat the reverse: The build falls a little short, but the sound quality is way better than the price would suggest. Seems to me, if you are going to fall short (and they all do one way or another), this is the way to do it. You give me great sound, and I'll forgive a few warts.

Yup, the SP330 is going up on the "Wall of Fame" based largely on its on its outstanding sonic performance. It does fall a little short on some peripheral issues (doesn't fold, no mic/remote, case is large, a bit underwhelming in design at the price), but to my ears, and to those who care about sound quality, this headphone is a big win for Koss. Whether it's a big enough win to give the company a much needed boost, I don't know...but it's a great start.


Koss home page and SP330 Product page.

Koss Corporation
4129 N. Port Washington Avenue
Milwaukee, WI 53212