Howdy,
I've been out of the headphone game for about 4ish years now. I never stopped using good headphones, but I haven't been purchasing anything so I decided to dip my toes in again and try out something Chinese, as I've been hearing that the stuff coming out of China has gotten quite good. (Run on sentence much?)
I decided as a Christmas gift to myself I'd pick up a pair of the Knowledge Zenith ZSX. I'm going to do a quick overview of my feelings about my other headphones so that we have something to compare to.
Sony MDR-7506: I really love these headphones. Like a lot. They're comfortable and built very well. Sound signature isn't terribly exciting. Bass is fairly quiet but quick and accurate, highs are clear without being offensive. Mids are present and not muffled. Soundstage isn't great, but no surprise there as they are closed back. This headphone is the pepperoni pizza of headphones. It's not exciting, but it's safe and man it is good.
Shure SE215: These are quite often my go to, and have probably spent the most time on my head. Sound is warm and inoffensive. Seperation isn't great and all of the frequencies seem to be more or less equal (with bass being a bit boosted). What I really like about these is how easy they are to listen to. I don't get listening fatigue from them because they are such a warm headphone. Soundstage is non-existent. My main gripe is that after a while they really seem to hurt physically, as they seem to create pressure points in the ear.
AKG Q701: I really really want to like these more than I do. But alas, I just can't. The fabled headband bumps really do start to hurt after a while. Not only that but I really dislike how they sound. Yes, the soundstage is huge, and that's cool. And yes, the highs and lows are extremely accurate. But goddammit the mids sound like garbage. I've never seen it mentioned in other reviews but the mids are badly recessed. And no amount of EQ seems to fix it. I listen to a lot of music where mids are vital and it's just a complete deal breaker for me.
Anyway, with that out of the way, here's the actual write up on the ZSXs.
To preface I'm just driving these out of my Xiaomi Mi A2 Lite using Poweramp. File quality is a mix of ~750-950kbps FLAC, 320kbps MP3, and some 192kbps wma (don't ask)
I do have a FiiO amp but will not be using it for this write-up.
Build Quality: They come in a really nice box, I'll definitely be keeping that around. The headphones themselves seem to be built very well. I'm not terribly impressed with the quality of the silicone tips but I will be replacing them with memory foam tomorrow. The headphones appear to be made of a high quality plastic and the zinc alloy faceplate is a nice touch (as well as the nozzle(?) being metal). I prefer the look of the ZS10 but I hear they're quite bright, and I don't love bright headphones so I opted for these. Anyway I wouldn't be worried about breaking these or anything, they feel quite sturdy. The cable they come with feels a bit cheap, but it makes up for it because it's designed in such a way that I can actually plug it into my phone with the case on. (For the Shure SE215 I have to use a short aux extension as the stock male end of the cable is too wide to fit in the cutout in the case for the headphone jack. This is also an issue with the MDR-7506, however I usually drive those as well as the AKG Q701 with an amp so it's less of a problem there.) My main concern with these headphones would be the cable connection at the headphone, it is not recessed and seems like it could be susceptible to breakage.
Fit/comfort: They pop into your ear easily. It took me a moment to figure out the technique coming from the SE215, but once you get it it feels very natural to put them in. Despite their rather large size, they fit into the ear very nicely. I find them quite comfortable, moreso than the Shures as they do not create pressure points in the ear the way the Shures do. They stay in firmly, and did not give me any trouble while I was pulling stock and putting together orders at my warehousing/distribution job. I would say I have average sized ears.
Isolation: It does have a vent so not as good as the Shure SE215, but still good enough that I couldn't hear my fiancée talking about Air BnBs for a trip we can't afford lol. Instead of being 100% absent to the world like with the Shures, you'll probably at least hear things like a gun shot or a text book being dropped. My point is, isolation is good. Microphonics(I think that's the word?) from the included cables is minimal. Something that drives me crazy about the Shures is how prone they are to noise from the cables.
Soundstage: It's an IEM, so don't expect it to be anywhere near as good as something like the Q701. It is better than the SE215, probably equal to the MDR-7506. For an IEM, I can't complain. Soundstage really is quite good for a headphone of this caliber.
Sound Quality/Signature/Separation: I don't feel like breaking those things down into their own categories so this is going to be one section.
The stuff coming out of China in general nowadays is ridiculously good (considering I'm writing this on a Chinese phone that I adore). This headphone feels quite neutral with ever so slightly bright highs. Bass is pleasant and responsive, much like the MDR-7506. However unlike the 7506, it does have a nice big driver specifically for the bass, and as such it can hang with my bassiest music. The bass does not muddle or bleed into any of the other frequencies, not that I can tell anyway. However I did notice that the higher end of the bass scale distorts just a little bit (the real lows however sound very nice). Highs are crisp and accurate. They're a bit bright but they're right on the threshold of causing fatigue. Mids are ever so slightly recessed but not enough to ruin the headphones like with the Q701. I just wish they were ever so slightly warmer. They sound a bit clinical, if that makes sense. I'd like to see how they would sound powered by a tube amp.
Seperation is what really blows me away with these. The first time I listened to a "busy" song with them I got a bit overwhelmed. Each instrument is so clearly audible, even when there's a ton of instruments being played at once. It does get a tad mixed up when listening to something like bluegrass, but the separation is better than any of my other headphones, and these cost half as much as my cheapest set. I imagine this is down to the 6 drivers in each side. My biggest gripe with them is that the noise floor is quite loud. Not sure why but my Shures don't do this.
Anyway, I think that's about it. Overall, I'd say these were a good buy, and can hang with more expensive headphones no problem. I like them a lot, and they will probably become my daily drivers.
I know many have talked about the connection issue, for now I haven't had any issues with it. However if I was to grab it with my fingers while it is in my ear the audio does cut out.
