I understood the sound of the KEFINE KLEAN as a V-Shape IEM, but it wouldn’t be wrong to think that it could be a variation of the Harman Target… although as I said, a variation, since each company makes some modifications to this tuning to the shape they find most interesting.
I evaluated the earphone with the Silver filter, which is intended to make the sound warmer. I can say that on the first listen, the IEM already showed that it would be a good product, I felt a very coherent and natural sound – to my ears. The IEM has a well-balanced sound proposal, you have bass, mids and treble, but everything is very well-balanced. Note that I will describe the sound with the silver filter… the details about the filters will be in the respective paragraph.
Bass:
Quantitative: I think the bass of the KLEAN is between moderate and moderate to high. There’s a good dose here, enough to please people who like bass. It’s not a basshead level, but it’s not an IEM devoid of bass either. Sub-bass and mid-bass are balanced, both with good presence. The extension is good, and I didn’t notice any roll-off. The KLEAN’s bass is great for a wide variety of genres, such as: EDM, Hip-Hop, Reggae, Samba, Funk, Rock, Metal, etc.
Qualitative: I found the bass to be strong, with good definition, good texture, good impact, body, depth, substance, and mass. The bass is well controlled, and doesn’t invade the mids. It fills out the presentation and so the sound is more inclined towards to the warm side. The bass certainly draws a lot of attention among the other frequencies, but I don’t think it’s boomy or muddy. Maybe in some situations it sounds a little bloated, but it’s like I said before, it’s a bass that has mass. Generally, the lower notes of a bass guitar are more full-bodied in the presentation. Everything is going to show that the KLEAN’s bass is more on the euphonic side, natural, rather than being strictly technical bass, like of the ultra-fast and dry type ones.
Midrange:
Quantitative and qualitative: Here, since I chose the silver filter, I got midrange that is very natural, that is, neither too recessed nor too frontal. As the silver filter itself indicates, the sound of the midrange received a slight touch of extra warmth in the presentation, which for me was something very welcome, since I don’t like IEMs with very high pinna gain, it makes me fatigue sooner (I tolerate treble even more than upper-mids). So, these are midrange that are well-balanced, during my listening, I didn’t feel any harshness, and I also didn’t feel as if they were far away or hidden. Great tonality (for my taste). The mids are well-defined and transparent, and I was able to hear everything with good performance.
Voices: For me, this characteristic of the IEM having a warm side gave a boost to the vocals with lower timbres, for example,
Dori Caymmi, the KLEAN manages to give a lot of texture and body to the singer’s voice. Now, this IEM have the trick of changing the filters – which you can see in the “filters” paragraph – and that is a plus in the product. Something that can be the solution for those looking for better performance for vocals with higher timbres.
Treble:
Quantitative: I think the treble is at a moderate level. Here the silver filter really did a good job, because even though it is a filter with less treble, it still left the IEM with a very good quantity, in the sense of balanced… neither much treble nor few treble, just the right amount. I think that this is great IEM for people looking for a more coherent presentation in this area, without excess. For me, these are treble that you can be sure of playing anything and nothing will go wrong. The extension is good, I didn’t notice any roll-off.
Qualitative: The treble are coherent, controlled, balanced, and fortunately they are also treble with good detail and definition. I also found the airy to be very good, especially for a single DD IEM in this price range. It would also be good to remember the
Simgot EW200, which in this region of higher frequencies manages to stand out a little more than the KLEAN – although with the black filter the KLEAN also reaches the same level as the EW200. The KLEAN has a very natural, comfortable sparkle, it’s an IEM that neither sounds too bright nor too dark. I didn’t notice any sibilance during the listening with the IEM. I also didn’t notice any abnormalities, no shrillness, no harshness, no fatigue. The sound of a ride cymbal has good detail and at the same time sounds comfortable, you feel the sound of the cymbal clearly and it doesn’t harm you.
Filters: So, the filters really do have a difference in sound… it’s certainly not a huge change for those who don’t have a trained ear, but for those who have been playing in this hobby for a while, you might be able to hear the difference. In short, the silver filter made the sound a little warmer – compared to the other filter. The silver filter has a slight recess in the upper-mids and treble frequencies, which for me, made the sound more natural, and yet it doesn’t lose detail, sparkle, voice projection, etc. With the black filter, what we have is the opposite, a slightly greater emphasis on the upper-mids and treble frequencies. Although it’s a subtle difference, you can really feel that some higher-pitched sounds like ride cymbals stand out more, and you can also feel that the mid-range is more “forward”, more airy and clear, so you can hear more crunch in the guitars, and more liveliness in the higher-pitched voices. So it’s a matter of choice. For me, the black filter makes the presentation brighter and colder. So I preferred the IEM with the silver filter, which, to my ears, had a good level of detail and was also more engaging. But note that changing the filter won’t change the sound drastically, like it’s either dark or bright. It’s not like that. The sound maintains the V-shape with both filters. With the black filter, I think it’s even more V-shaped.
Soundstage: I thought the KLEAN’s soundstage was good. It’s an IEM that sounds very open, has good spatiality, a lot of height and width, not so much depth… and maybe that’s exactly what I felt, because the IEM didn’t offer me anything like a layered soundstage. This also draws attention to the IEM’s image.
Imaging: So, as I said above, you have good spatiality, and this prevents the sound from sounding congested or compressed. Now, I think it has a limit of performance… probably because I’ve heard IEMs that I consider superior in this regard. And also because I believe that hybrid IEMs – generally – achieve more instrumental separation. In short, it’s a good/ok separation. For a single DD of this price, it’s great. If you’re looking for a single DD with more performance in this regard, perhaps the
Simgot EA500LM is an option (although at a higher cost).
Driver flex test: I didn’t heard any driver flex sound when inserting the IEM into my ears.
Amplification: I used the
FiiO KA11 dongle connected to my notebook to perform this review. The volume was set to 25% of the 100% available through Windows. I can say that the KEFINE KLEAN is an easy-to-play IEM that doesn’t require dedicated amplification. The KLEAN will play well on smartphones, iPads, and computers. As usual, I recommend that the user at least have a good quality
dongle to play your IEMs. Currently, I recommend the
FiiO KA11 as a good cost/benefit dongle.
