Omg I didn’t expect these to be so similar to EX1000. Super exciting!
Yes, the Luna is in some ways quite similar to the EX1000. Although, in other ways, it isn't. For instance soundstage, separation and imaging reminds me more of another old favorite of mine, the Final FI-BA-SS. While the EX1000 has an extremely wide stage with not that much depth, the Luna is not as wide, but feels more 3-dimensional. Also, the EX1000 has a more "blended" sound, somewhat reminiscent of a live venue with room reflections. The Luna, on the other hand, presents everything very separated (like the FI-BA-SS), with every instrument clearly carved out and located in its place, more like what you'd expect from a studio sound.
It's pretty exciting to have a brand-new IEM at hand, that surprisingly seems to combine the traits of two old favorites of mine, from many years ago!
This being said I owned and ended up selling EX1000 because of its agressive peaks it's no on every recording but when it is then it's piercing to me...
I feel it's similar with the Luna, though to a somewhat lesser extent. But the upper mids and treble tuning is one potentially controversial aspect of the Luna in my book.
I've spent some time A/Bing the Luna to the two IEMs I use most frequently these days, my JVC FD01 (modded, identical to the FDX1) and my FAudio Passion (modded). Both of the latter IEMs have a less peaky and more balanced high range than the Luna, as illustrated in this measurement:
(High range comparison > 1kHz, DF-compensated) red = Dunu Luna, blue = FD01 (mod), green = Passion (mod)
Now, the Luna's tuning is interesting and pretty clever, because the high-mids emphasis around 5kHz gives it a lot of presence and clarity, while the wide scooped-out range higher up prevents it from sounding sharp or sibilant (the ubiquitous downside to so many other "detailed-sounding" IEMs).
However, this clever tuning comes at a price, since it introduces a bit of harshness (mostly noticeable with complex classical music - see example below). And it sort of throws the high-mids / low-treble timbre a little off balance (mostly noticeable with rock music, where electric guitars have almost Grado-like edge and bite, but cymbal crashes sound rather laid-back in comparison, with somewhat subdued sparkle and shimmer - see example below)).
So, while the Luna surpasses both of my current favorite IEMs with superior perceived detail / clarity / separation, the latter succeed in reproducing the high range with slightly more smoothness and better tonal balance.
Example #1: Excerpt from Mahler 2nd symphony, listen from 01:30 to 02:30)
Example #2: Matthew Sweet - Girlfriend