zs6 highs peak was excessive. but after our discussions, kz decided to roll-off highs in every posterior iem.
please, don't ever mention that zsn have treble cannons (which is completely false, it's the opposite, treble is rolled-off), or treble will disappear completely in next kzs. at last, kz will end making old fashion muddy bloated bass iems..
i'm not going to purchase kz anymore, till they restore acceptable treble levels
If you look at the reviews of the ZSN here and elsewhere there were a lot of compliments about the treble along with comments about the treble being enhanced over what people considered neutral, but no real consensus on whether the treble was rolled off:
"Some occasional sibilance (especially with female vocals)"
"Treble is still more aggressive than need be and can be sibilant at times"
"Steely Treble"
"Emphasis on the Sibilants, sometimes sharp trebles and strong peaks"
"If you want to get picky, occasionally harsh in the upper mids and treble"
"Treble is more prominent than midrange, but its tuning makes it so that it is not that noticeably in front of mids. Extension is in fact very limited and this leads to a situation where the lower treble is emphasised, mid treble is recessed and upper treble is almost non-existent."
"The ZSN’s treble is probably better than it should be for a $20 IEM as well. It’s crisp and lively with good extension but doesn’t have any harshness."
"The KZ ZSN highs are very bright and resolve a nice amount of detail. These are not rolled-off sounding earphones yet they do not become nor overly fatiguing. People looking for bright highs will like the KZ ZSN. Piercing highs might show up from time to time, as expected with this style of tuning but, unexpectedly, they did not show strong nor frequent sibilance."
It's possible that the disagreements about treble have to do with the shape/fit in people's ears and/or their age (the older you are, the more high frequency hearing you loose, so the ability of a listener to determine if a headphone has excessive highs is reduced the older they get - i.e. you could make headphones with a nasty 19kHz peak and people over 40 would never know).