Disclaimer: I purchased the Ocharaku KURO and KAEDE units used for this review directly from Ocharaku.
People often ask me what I’m listening to, and these days it’s been mostly the Ocharaku Flat-4 IEMs. The Ocharakus are not easy IEMs to sell or to recommend. As a top-of-the-class acoustics IEMs, they happens to be ruthlessly revealing. Not only does it demand the highest quality recording but also source quality. As hard as I tried to be the Ocharaku evangelist, my efforts haven’t been so successful. The sound usually comes out pretty nasty when you start playing mainstream recordings on it, and the majority of people who I’ve showed the Ocharakus to are mostly unimpressed with the sound they hear. Nevertheless I truly feel that there is something special and brilliant with these Ocharakus and so I’ll take the risk to be unpopular.
The IEM market is getting saturated with thousands of new models. Everyone is making IEMs these days, and there are a lot of affordable products with good sound (i.e Vsonic GR02, XKDunn CK700). It looks like manufacturers are finally getting a pretty good idea of what makes a pretty decent IEM. The average $100 IEM has enough technicalities for the average mainstream music, and as long as you stick with balanced armature drivers, you shouldn’t have any problem resolving the average complex passage on a typical fast-paced music. Add one or two drivers for the lows and bass should be plenty with good control and punch. Some manufacturers like a more romantic tuning with plenty of treble sparkle while others prefer a more mainstream music oriented tuning. If innovation was to stop at this very moment, I doubt any of us would have any complaints or objections.
Surrounded by this sea of well tuned, affordably priced IEMs, Ocharaku entered the market with a revolutionary design that promises to push the acoustic limits of in ear monitors. I really wouldn’t care about the technology if I can’t the results in the final product. Not so with the Ocharakus. I’ve compared them to most the top tier IEMs in the market and I don’t think there is anything else better in terms of acoustic qualities. Listening to what Mr. Yamagishi (the Ocharaku designer, the ex Sound Director from Sony) has to say, I’m convinced that this guy is the leading man in the world of in-ear-monitor acoustics.
Regardless of how uneasy the tonalities of the KURO and the KAEDE are for my dark-loving ears (please give me a HD650 like tonality!), I can’t help but falling in love with the acoustic qualities in the Flat-4, especially the Maple-housed Kaede. While Hadi came out feeling pretty impressed with the entry level Ocharaku Flat-4 SUI in his review, the Flat-4 KAEDE (flagship, maple wood housing) and the Flat-4 KURO (the latest model, mid-line product, anti vibration aluminium housing) are quite one and two leagues ahead of the SUI.
The mid-line KURO is based from the SUI but with the added benefit of improved acoustics thanks to the hybrid anti-vibration coating on the aluminium housing and the phase correction tube. The result is a sound less honky on the midrange than the SUI, a more neutral and uncoloured midrange and a lower hitting bass (I love this part–though all the Flat-4s are quite tame in bass). I was immediately hooked to the KURO from the moment I first listened to it at the Tokyo Headphone Festival as it was a definite improvement from the SUI. Briefly comparing it to the flagship maple housed KAEDE, I even thought that the KURO seemed to be the better model thanks to the lower hitting bass which the KAEDE can’t match.
The Maple Housed KAEDE
Longer listening time however brings more appreciation to the flagship KAEDE. There is a soft wood timbre that reminded me as when you upgraded to the metal housed Grado SR325is or Alessandro MS-2 to their woody housed big brothers. The wood timbre though not as strong as on the Grado/Alessandro woody models (none other headphones are), the timbre though a bit on the drier side (perhaps Mr. Yamagishi can try a different wood type) sounds softer and more romantic compared to whatever material FitEar, Sony, AKG, and Sennheiser are using on their flagship IEMs, and also Ocharaku’s own aluminium KURO. After all, there is a reason concert halls and recording studios are dressed in wood.
The tonal balance of the KAEDE pushes the midrange a tiny bit forward, making it a mild mid-centric IEM than the mildly v-shaped KURO and again this is preferable to my ears. However outside from the tonal balance difference which usually is a subjective matter, once I hear the subtle wood timbre and the soft decay, the KURO simply sounds too metallic and cold. And since we’re going with Ocharaku to get the best acoustics possible, I say may as well jump all the way and reach for the Kaede.
Even more lovely is the sweet sound of coherence that I don’t hear even from the single driver Sennheiser IE800, and even worse on the quad-driver 334ToGo (which to me is the best multi-driver BA IEM in terms of coherence). Funny because the Flat-4 is actually a dual-driver design, though the twin drivers are not configured to both cover the full frequency range (they both cover the full frequency range), but comparing the Flat-4 to the IE800 (and I’m a big Sennheiser fanboy as you all know), I really think that Mr. Yamagishi’s FLAT-4 Kaede has bested Axel Grell’s best IEM in terms of acoustic qualities. I don’t understand how this could be, perhaps housing acoustics issues, but the IE800 actually has issues in the midrange that somehow affects the perception of coherence, making the single driver sounds like it has phase issues in the midrange. Obviously the IE800’s darker, bassier tonality, fits my ears much better than the high-mid-centric Kaede, but the superior acoustics and resolution is really making the IE800 sounds like a 2nd-tier flagship IEM in front of the Kaede. Midrange transparency, soundstage size and depth, driver resolution, micro detail and dynamic range, all unmatched by the Senn.
Play some well recorded classical music or audiophile Jazz and it doesn’t take long to notice the acoustic superiority and the superior detail retrieval of the Ocharakus that even made the 334ToGos sound lacking detail. Still, we sell a lot more 334ToGos at the store than we do Ocharakus, as the FitEar simply has a much more pleasing tonality and plays better with a wide range of recordings and source. Heck the popular Vsonic GR07 is even more musical to listen than the Ocharaku Flat-4s. The problem with the Ocharaku is that it’s like taking a car designed for the track to be a daily driver. It corners as if it was on rails, but only if you give it race track quality asphalt. Driven on ordinary road, you hardly feel any quality other than that the ride was bumpy. The average driver driving through the typical downtown roads would all vote that the Lexus has a better suspension than an F1 car. That really is the situation happening with the Ocharakus. With the superior resolution, the Ocharaku Flat-4s give you a clearer picture of what’s happening in the recording, and these days there are far more bad recordings than there are good ones. Just like the race car driver suspension, you’ll really feel every bumps and potholes in the recording and the result may be extremely tiring to the ears.
These are not exactly “the sound of music” as in everything is musical and enjoyable. Rather, these are “the sound of truth” as in the real truth about the recordings. And just like in the real world, often we’d rather not know the truth as the truth can be very unpleasant. For instance, they’ll let me really listen to the grain and texture of an old AAD recording, while other IEMs somewhat present a masked-out picture of the grain. Yet, while I enjoy this sort of a transparent playback, it does get tiring after a long listening time. But still I go back to them the next time as I simply can’t go back to the sub-par acoustics of the other IEMs. I really won’t recommend them for a first time IEM owner, nor do I recommend them if these are going to be your only IEMs. You may be a track car buff, but still you need a daily driver with a soft plush suspension and perhaps also a 4WD for the winter months. Likewise the Ocharaku: I don’t call it brutal for no reason.
If you’d like to read more about the technology behind the Ocharaku FLAT-4s, I’ve uploaded the Ocharaku tech document to Headfonia’s server and you can download the document by clicking on this link: Technology of OCHARAKU_English