The headphones from the Taiwanese music equipment manufacturer Superlux ( go to the overview) have regularly secured top positions on our price-performance leader board in recent years. And they have done so with remarkable continuity because, despite price tags that are regularly in the lower two-digit range, there have been, and still are, no really bad drop-offs in quality. The new HD330Pro semi-open studio headphones continue this trend in fine style. The design of the Superlux HD330Pro Bottom line, if you want to listen for errors in music, these will help you find them. If that doesn't sound appealing to you, I'm not surprised. I do think that's what they're made for though, and they do a damned good job of it. It's obvious that the HD668B have adopted design elements from several AKG and Audio Technica headphones. Deep bass extension on my HD861 is minimally better by ca. 3 Hz, but not much and only audible when performing sine sweeps.

Though the headband spring-wire felt solid, these wings felt a bit flimsy in comparison, especially a thinner wire attachment - just have to be more careful when taking these headphones off you head. Closer to earcups, the headband wires are held together with a plastic joint piece on each side, kind of reminding me of “y-splitter”. These pieces look to be replaceable, if needed, and made of a solid plastic material. I found HD668B to be relatively comfortable to wear, and with evenly distributed 220g of weight it felt feather light. Pretty clean sounding bass that is only a bit on the softer side. Details are good, but not the most separated (sounds a bit blunt), despite being fairly tight and fast. Sub-bass also has a satisfying goodness. There’s a nice weight to it and a fast, controlled rumble which, similar to the mid-bass, does not intrude over the midrange. The HD668B revels in its control here, bringing the party without the associated hangover.

Lots to Love for a Low Price

As for comfort, it isn't that good at first, as it has quite a strong clamping force, but it does get better with time. After a while, you can't even notice you're wearing them. Highs: Without EQing the highs can be harsh and piercing with some records, bad mastered or low quality mp3s can be tiring to hear, taming the highs reveal very decent and detailed heights.

That’s not too shabby considering the price you’re paying. Having the two cables provided is really something I wasn’t expecting but it’s very appreciated and also a very practical addition. At this point, just seeing my first glimpse of the headphones and the two cables, I was already thinking what great value this is. If you are looking for a good isolation, these are definitely not the best for listening on the bus or in the library, after all - this is a semi-open design. But it wasn’t leaking as bad when you step away 2-3ft. I’m sure some will find this semi-open design even beneficial since it could raise the surround awareness without losing too much of the sound details. As I have found with pretty much every headphone (except IEMs) more clean power adds to the extension and balance. The Bass got some more growl from the Project Polaris as well. HD668B vs SoundMagic HP150 - HP150 soundstage comes closer to HD width, but not quite there, and HP150 has a little more depth. Also, HP150 sub-bass reaches deeper to the same level as HD, but a little shy of HD quantity, and mid-bass in HP150 is a bit lower in quantity as well. HP150 lower mids are leaner and upper mids are a little more upfront and brighter with an advantage of slightly improved retrieval of details. Treble is rather similar, being crisp, bright, snappy, and with enough extension and airiness to make the sound more resolving and layered. Actually, after closer listening I hear HP150 being a little brighter in upper mids/treble. Except for the headband and the holders for the "wings" that rest on your head, the headphones are made of plastic. They dont squeak or rattle when handled, but apart from that, there aren't many more nice things to say about the build quality.

Bluetooth Function & Sound

The soundstage is on the smaller to average side with almost as much spatial depth as width. Regarding size, it is circa as wide as the space between the ear cups and stops around where my eyes are located. stars: The product is good/very good, but not outstanding/special enough to get any of my two awards. ["Thumbs Up"]

Enough blabbering - these headphones are absolutely worth the price. The sound is pretty clear and the phones are comfortable to wear. They are a little bass heavy though so keep that in mind if you are considering between these and some other ones. But for my purpose, casual music listening while in work, they are just perfect. They are semi-open, but I'd be ready to call them open. It's good when someone tries to reach out from outside as they don't need to shout. On the other hand they are massive enough to be seen so other understand that they might need to raise voice — good perk compared to earphones. Therefore, the Fostex’ bass rendering is cleaner, tighter, faster, better controlled as well as better layered; in the mids, they are more layered and detailed as well as refined sounding, which also applies to the highs. On the good side however, there are so many things sound-wise for the price and even without knowing the price tag. In the mids and treble, both are more or less on the same level with the HD681 only sounding airier because of its tonal tuning. The HD681’s treble is probably a slight bit cleaner however it is more aggressive as well as edgy. The same goes for the treble where the HD681 are brighter and peakier – out of the two, the HD668B are definitely the better-tuned headphones.There is no height adjustment like in traditional full size headphones, and instead you have soft foam “wings” on a spring metal wire which self-adjusts as you put headphones on. This could be hit-or-miss with some people who have big head or curly hair (the last comment actually came from my wife). For me personally, it works quite well since I’m already accustomed to ATH-R70x and ATH-A2000Z, both of which have a similar “wings” headband support. Treble is way to Hot, particularly the highs. This could be attributed to the multiple relatively large peaks which are present at around 2k, 6k, 10k, and 15k (thanks to Rtings.com frequency chart). The biggest peaks are present at 10k and 15k. As a result the headphone sounds very unnatural and harsh. I would not consider myself a treble sensitive person but the super boosted highs just make it sound so unnatural. Like Tyll from Innerfidelity said, I have to admit these do sound pretty decent IF you EQ everything from around 1.5kHz gradually down to 5dB or even more.