Komuro

Well, the time has finally come. After quite a bit of thinking, and perhaps an equal amount of trying to talk myself out of it, I’ve ordered a Komuro K-300S amplifier.
I had the opportunity to buy one from the first edition, but for whatever reason I was either too stupid, not ready, or simply did not quite understand what was being offered. Probably a combination of all three. I watched that opportunity disappear and have regretted it ever since, so when the second edition was announced, I jumped at it. Some mistakes don’t need to be made twice.

The K-300S is a 300B single-ended power amplifier producing seven watts per channel in pure Class A. It uses a pair of 6BM8/ECL82 input and driver valves, a pair of 300Bs and a single 274B rectifier. More interesting than the basic specifications, though, is Noriyasu Komuro’s unusual direct-coupled circuit. From the input to the custom output transformers, the signal passes only through wire and valves, with no coupling capacitors, interstage transformers or circuit boards in its path. The amplifier is point-to-point wired and uses custom C-core transformers and chokes, with considerable attention paid to isolating the signal circuit from vibration and interference.

Komuro Amplifier Company was founded by John DeVore in 2020 to bring the designs of Nori Komuro into proper small-scale production. Komuro’s amplifiers have acquired an almost legendary reputation over the years, but fewer than a dozen were built by Komuro himself. The new amplifiers remain handmade in Brooklyn in very small numbers and continue to use his distinctive direct-coupled circuits.

The revelation of the EM/IA autoformer line stage, followed by my time with the Audio Note 300B amplifier, has been extremely instructive. Together they have shown me just how satisfying a very simple amplification chain can be. A passive transformer feeding a single-ended directly heated triode amplifier may look almost wilfully basic on paper, but the immediacy, space, low-level detail and sheer musical presence I have heard from this approach have been difficult to forget.
Electrically, the Komuro feels like the natural conclusion of where my system has been heading: the EM/IA autoformer feeding a direct-coupled, single-ended 300B amplifier, driving the DeVore Fidelity O/Bronze speakers. It is difficult to imagine a much simpler path from source to loudspeaker, at least without becoming completely impractical. Simplicity is no guarantee of musical satisfaction, of course, but when it is backed by this level of thought, experience and execution, it becomes extremely appealing. I’ve chatted with a couple of people who have heard the pairing of the K-300S and the O/Bronzes and they all reckon to go for it, and who am I to argue with sensible reasoning?

Unfortunately, ordering the Komuro also means that some rather serious funds now need to be released. My Kondo Overture PM-2i integrated amplifier and matching Kondo GE-1 phono stage will therefore both have to be sold. Neither is something I ever expected to let go, and certainly not because I have fallen out of love with what they do. The Overture and GE-1 have been at the heart of some genuinely wonderful listening, and moving them on will be the painful part of this change.

But the order has been placed, the decision has been made, and this time I was not going to let the opportunity pass. Now comes the difficult business of waiting, to both sell the stuff that needs selling, and for the amp to get here once that happens. I also have plans for some nice tubes for it, as suggested above. Good things come to those who wait…