This and That:
No carrying case included - not surprising as Knowledge Zenith want their customers to buy it extra to make more profit. The same goes for the cable as the bundled one is only average-ish at best. That's not something I support but still okay-ish for the price.
Build quality is good. I don't like the three vent slits though.
Is it a parody to the Campfire Audio Andromeda? Perhaps. The sound signature, colour and design indicate that it may be, just like the purposely (?) wrong spelling on the shells. Anyway, I don't care and am digging the design (except for those three vent slits).
To my ears, the ZS6 is a bit less comfortable than the ZS5's plastic shells.
If there are several generations of the ZS6, as it was the case with the ZS5, then I've got the early one since I got it right after release.
Sound:
I'm only using the ZS6 with the largest included silicone tips and only with low impedance source devices.
Tonality:
On the inside of the ZS6 (and ZS5) there is a vent, which directly affects the bass quantity of the in-ear, depending on how much it is covered, depending on the individual ear anatomy of the user. When the vents are completely open, the bass elevation is about 9 dB compared to an in-ear that is diffuse-field neutral in the lows, such as the Etymotic ER-4SR/ER-4S, whereas when the vents are completely closed, the bass quantity is about 12 to 13 dB.
The latter is the case in my ears.
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The ZS6 doesn't sound that much different from the ZS5 in the midrange and bass. However, there are clear differences in the treble.
In general, the sound of the ZS6 can be described as quite v-shaped and is not completely unlike the tuning of the 1More E1001 except for the upper treble, but I will discuss this in more detail in a separate comparison section below.
The hybrid quad-driver in-ear by Knowledge Zenith has a powerful midbass and still a strong sub-bass.
In the vocal range, it is somewhat on the brighter side, which is due to its raised upper midrange/lower treble of around 3 kHz, but this emphasis is weaker than that of the ZS5, making the ZS6 appear a little less hollow and thin in the midrange, although it has the same tendency (so the ZS6's mids are more realistic in comparison).
Central treble level is reduced again to create headroom for the emphasis of the upper mid-range and the emphasis of the beginning super treble. And it's precisely this emphasis on the upper/starting super treble that fucks up the ZS6's treble, as it is simply too much and too sharp. Accordingly, the ZS6 sounds noticeably sharper, more metallic and more sibilant in the upper treble than the ZS5 (first generation). So what the in-ear does a bit better in the mids doesn't matter as much as its upper treble is clearly too energetic.
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The bass emphasis begins to rise slowly at about 450 Hz and peaks at about 60 Hz with an increase of about 13 dB compared to an in-ear that is diffuse-field neutral. There's only a very mild loss of energy in the very low sub-bass; nothing that could be described as a roll-off, so the sub-bass is there in its fullest if the recording allows it.
The way in which the bass accent rises and reaches its climax even more deeply is quite well done, as it avoids an overly warm and boomy fundamental range as well as a lower midrange as far as possible and gives deep voices only a little extra warmth. Nevertheless, the ZS6 is definitely not a vocal-oriented in-ear due to its v-shaped tuning.
What is largely avoided in the fundamental, however, takes place to a certain degree in the midbass, which can occasionally appear a little boomy.
With a sine wave generator I hear that the midrange level rises evenly from 1 to 3.5 kHz and thus generates a more airy tuning, but is not exaggerated and is not as strong as the ZS5's upper midrange lift that made voices sound a bit too hollow. Above that, the level drops a bit and ends in a dip between 5 and 6 kHz.
Around 10 kHz the ZS6 makes a gross error - here it has a strong peak which is between 10 and 15 dB louder than the ZS5 (for info: an increase of 10 dB is perceived as a doubling of the volume).
Thus the ZS6 sounds quite sharp, sibilant, unnatural and metallic in the upper treble.
If you're not a hardcore treblehead, this can definitely be seen as an unforgivable flaw. Only in recordings where not much happens around 10 kHz, as well as in the radio playback of my Apple iPod Nano 7G, the upper reble seems tolerable and not exaggerated, even though it is indisputably bright. Or alternatively if you connect the ZS6 to a device with a really high output impedance, then the sharp peak is reduced thanks to the in-ear's impedance response that drops towards the upper highs.
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While I still attested the ZS5 to harmonize quite well with "modern" music due to its tuning, unfortunately I can't say the same for the ZS6 due to its sharp, sibilant upper treble. Thus the in-ear wastes a lot of potential. Ironically, unlike the ZS5, the ZS6 works best with vocal-heavy music that doesn't have any instruments that extend particularly high. Both rather suck when it comes to ultimate timbre though.
The ZS6's powerful emphasis is very high in the frequency spectrum, so it's not always problematic and the in-ear doesn't always sound metallic and sharp, however it still sucks and is over-accentuated (using low impedance sources) wherefore cymbals become nothing more than an unpleasantly sharp, metallic hiss.
Resolution:
For the price, the detail level of the ZS6 is good - especially in the mid and high frequencies, the in-ear appears relatively detailed and neatly separated, but without achieving the resolution and separation of some models of the >$100 class.
Although the bass is qualitatively adequate for the price, it doesn't have the highest speed and tightness, even though it seems a bit less soft and slightly better defined compared to the ZS5's lows. Nonetheless it still doesn't approach the speed and tightness of the Xiaomi Hybrid Pro HD.
In the midrange, the ZS6 doesn't really have a weakness and separates individual elements neatly to well from each other and would do a very good job for a backup or budget in-ear if the problematic upper treble didn't exist. Compared to the ZS5, the resolution in the midrange has increased slightly when comparing both side-by-side.
Soundstage:
Where the ZS6 can score points again is the spatial presentation, which, in terms of its precision, stands out from the budget range.
The stage size of the in-ear is not particularly worth mentioning and is quite average in its size, but not narrow, with a width-to-depth distribution of about 60 by 40%.
The instrument separation and location accuracy, on the other hand, is good and you get the feeling of a fairly accurate and coherent stage, which to perfection in the budget range only lacks a little more accuracy in depicting "emptiness" between individual instruments.
In terms of accuracy, the stage of the ZS6 is identical to that of the ZS5 in my ears. The ZS5's appears a bit wider though.
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Compared to other Hybrid In-Ears:
Knowledge Zenith ZS5 (first Generation):
Both in-ears have the same amount of bass and an almost identical bass boost (the ZS6 sounds only slightly fuller in the upper fundamental range).
The ZS6 has also got a clarity emphasis in the upper mids, but it's not as strong as the ZS5's wherefore its voices appear somewhat more realistic in comparison.
In the (upper) treble, however, things look quite different again and the ZS6 loses its advantage due to its overly powerful, sibilant and metallic emphasis.
When it comes to detail resolution, both in-ears don't differ much - the ZS6 only appears slightly less soft in the bass than the ZS5 and is somewhat better defined in the bass, and the resolution in the midrange is also a little higher, but there are by no means any significant differences (nor are they nuances, though).
In the end, these small advantages don't really matter because of the fucked up upper treble.
As far as the stage of the two in-ears is concerned, that of the ZS5 is a bit wider, while in terms of spatial precision there is no advantage in favor of either of the two in-ears.
1More E1001:
Tonally, the two in-ears, as was already the case with the ZS5 and E1001, are not too dissimilar, although I consider the ZS5 to be more comparable to the 1More due to the overly motivated upper treble of the ZS6, although the ZS6 is more similar to the 1More in the midrange than the ZS5.
The 1More (at least if its inner vents are naturally blocked) has more bass and midbass quantity than the Knowledge Zenith in-ear and is a bit warmer in the lower midrange.
In the upper midrange, however, the 1More is a little brighter, which is why I'd consider the ZS6 more realistic than the E1001 in the midrange (if it weren't for the highlighted sibilance due to the strongly emphasised upper treble). Nevertheless, the E1001 sounds a bit "hollower" in the vocal range than the ZS6 (which is a contrast to the ZS5, because in this comparison the opposite is the case and the ZS5 sounds more distant and hollower in the mids than the 1More).
The 1More also has an audible emphasis in the upper treble/beginning super-high frequencies, which results in some metaliness, but the ZS6 emphasises this range earlier and with 5 to 10 dB more quantity, which is why Knowledge Zenith's in-ear definitely sounds sharper, brighter and more metallic than the E1001 in the upper highs - a real pity.
In the mid-range, both in-ears are equal, while the 1More still has a small advantage in the treble in terms of detail resolution.
In the bass range, both in-ears don't have the best dynamic driver and sound rather soft and slow. Even though the 1More has a slightly tighter bass, the texture of the Knowledge Zenith's bass is minimally better.
Both in-ears have a similar stage size with a small width advantage for the Knowledge Zenith in-ear.
The ZS6 is a little better at displaying emptiness, whereas the 1More has a more precise instrument separation.
Conclusion:
Decent to good everything coupled with a fucked up upper treble peak. Ultimately I'd even say the ZS5 is the easier recommendation, and it was already an in-ear that had some distinct flaws.