I can't speak to the sound of any Kondo amp, as I've never heard them, or the OBX-R2's with any amp but my NAF 845 SE. I will say that this amp gets timbral nuances right in a stunning way, whether the raspy bark of a tenor sax, or the purr of a cello. Vocals are sublime. With the OBX-R2's being as transparent as they are, these qualities were nakedly apparent. I was often drawn in by the small details that great tube amps reveal, the breath of air through a flute, or the slight sound of moisture in the voice of a jazz chanteuse. Percussion instruments were particularly entrancing. If there are any Max Roach fans out there, the Japanese CD transfer of "Drums Unlimited" (not the version with "Hassan") is unforgettable on these speakers.
Regrettably, I recently sold my OBX-R2's for a small number of reasons. Primarily, I missed my Reynaud Offrandes, which offer similar qualities, but in a more full bodied, warmer, only slightly softened presentation. In comparison, I found the LV's a bit lean at times. My wife also greatly preferred the look of the Offies. I think the crossover boxes of the OBX-R2's were a bit much for her.
It's a shame that the New Audio Frontiers products don't generate much discussion in these groups lately. I think they are a great buy at the prices set by the new distributor, and an outright steal at the used prices when they show up on Audiogon. I've been through many fine tube, SS, and digital amps over the years. None have floated my boat anywhere close to the 845 SE
