Ratoc Audio Labs KEB-O3 Portable DAC/AMP, Mini-Review & Question

[LoryWiv]

I've not seen much written about this DAC/AMP here or on Head-Fi, but I wanted a portable to stack with my DAP and to run balanced output to my 64 Audio A6, that would also serve me well as a USB DAC for PC. I took a leap of faith on this unit, bought from Moon Audio, and thus far pleasantly surprised by it's quality. The unboxing and ergonomics are nothing special, rather plain and uncluttered in appearance:

That said, implemented thus far as a USB DAC from PC (still waiting for proper interconnect to stack w/my DAP using the KEB-03 Toslink input) I am impressed with it's sound signature. Using the 2.5 mm TRRS, AK-type plug on my IEM's, the balanced output achieves wonderful, wide soundstage, although depth and height are less impressive. Layering, instrument placement and separation are also strong points. I do feel it lacks some of the detail retrieval of my iDSD Micro., and whereas the Micro. brought out the lower frequencies in my A6, KEB-03 synergy with these IEM's provides a more neutral frequency response overall. The iDSD / A6 combo. has visceral, impactful bass but bleeds sometimes into mids. With KEB-O3 I hear a bit cleaner, grain-free and more forward mids (vocals sound terrific) and greater top end sparkle. The Micro. doesn't have balanced out put, so this may account for the soundstage / separation difference in part, but the overall signatures sound different beyond that as described. Both have Sabre DAC's, which I sometimes find a little sterile, but as implemented in the KEB-O3 signature is overall more balanced across the frequencies, quite musical, and less "digital" sounding than I sometimes perceive with the iFi Micro. I'm not very well-acquainted with "tube" sound but from the auditioning I did last month at CanJam SoCal. of the Woo Audio and other products, the KEB-O3 sounds more "tube-like" to me than the Micro. and suits most of my material well. I listen to a lot of classical piano, and the sound is nicely balanced, engaging across the frequencies but never shrill or strident. For classic rock or acoustic jazz featuring standup string bass, I do miss the low end "punch" the Micro. coaxes out of my A6 that the the KEB-03 can't quite replicate.

 

Overall, I'd conclude that the KEB-03 offers great value for a moderate price, and strengths are the balanced output producing wonderful soundstage and instrument separation. Weaknesses are that it falls short in detail retrieval and bass impact, and I would add that it is not a powerhouse (balanced output is 131mW/channel @22 ohm load) and may be best suited for IEM's or low impedance / high-sensitivity cans.

 

Lastly, a question: The manual (here) indicates it can decode native dsd via USB but I can only get it to do DoP in Foobar. I have foo_dsd-ASIO installed, works fine with iDSD Micro. The manual appears to be translated from Japanese so I may be misreading it (it could be indicating that native DSD is implemented for Android USB OTG), or perhaps I have Foobar configured incorrectly. Any help would be appreciated.