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Round 2. AudioSolutions Rhapsody 200. Using the prior sentence as lead-in segues straight into a predictive answer. Dark, warm, weighty, bassy—my usual brief for the AudioSolutions is "vintage Sonus faber voicing with US-style bass and high dynamics"—looked into the mirror. At lower levels this compounded even more. I wanted for the higher insight and twitchier reflexes of the Meraks. My very best option for the friendly Lithuanian lumberjacks really is the Crayon's whisper-level lucidity. The Bakoon and FirstWatt monos lack power and the latter won't control the underdamped twin ports. The SPEC clearly had no issues with the quite erratic phase/impedance angles of this load. No port boom, no mush. Its own voicing would simply have better complimented a far more neutral Amphion, the recently reviewed very quick Accuton-fitted Albedo Audio Aptica or an equivalent but big Mårten Design or Kharma tower.


Of course that statement betrayed personal bias. Were I a Spendor or Harbeth fan looking to maximize the known virtues of those warm Brit boxes, the RSA-M3EX could be it. Hence Polish contributor Wojciech Pacuła with his Harbeth M40.1 Domestic maxi monitors should be a perfect target-group spec(i)men. No wonder his review of their phonostage netted an award. If we distill our earlier introduction into the sound of vintage paper-in-oil caps, we have another confirmation. In our context none of it comes as a surprise then.


The thing is, given class D's early criticisms—which haven't applied for a number of years now—it remains good form to reiterate that the breed's pendulum on a whole has since swung in the opposite direction. Whilst especially for Ncore it's swung back a bit again but moved to a higher level, with the M3EX it's stuck in the maximal counter position. As such Shirokazu Yazaki's stated goal has been met. It really is about a powerful dose of classic valve sound. The big difference is cool running power; current-critical load happiness into low impedances; operational silence; and stable performance without the insidiously slow aging of power triodes and its deleterious sonic effects.

With that pegged and the white towers too similar to veer more deeply into the same direction than suited my personal tastes—someone else could feel happily married however—I was curious. How would the Japanese get on with my Boenicke Audio B10? Where the Wave 40 are my Swiss eggs, the B10 are the Swiss slivers. Once you see their span-by-hand width you understand.

Round 3. Boenicke Audio B10. Unlike the power-matched Crayon which eliminates signal-path capacitors and with it low-frequency phase shift (very good!) to produce a type of 'turbo' effect on these sidefiring woofers (too much for my short-wall setup), the M3EX didn't upset the tonal balance. As had been the case on the white towers, woofer control was once again spot on. Whilst not lucid/quick like the Crayon and with rather less energy in the upper octaves, this was as fine a pairing as the eggs had been. Extending lower without being plagued by ports for superior sealed bass, the ambient-rich sound favored by Sven Boenicke—hence his penchant for lateral drivers—responded favorably to the amp's tonal weight. I really suspect Yazaki-San himself would have approved.

So would Kevin Scott, Living Voice designer and author of their superlative Vox Olympian hornspeaker. Doubling as the UK's importer of Kondo Japan he favors succulent operatically dramatic sound to detest monochromatic tone colors. I seriously doubt Kevin would ever even consider class D. He's still a PC audio virgin. Just so the M3EX would surprise him just a tick. It really wears its tube lover's heart on the sleeve. As such it could only have been created by a devout SET fanatic. And perhaps the only country open-minded enough on hifi matters in the first place to pursue the strange arc of 300B direct-heated triodes to rapidly switching DirectFet transistors was Japan. So toss the rule book.

Wrap. SPEC's pricing too relies on open-mindedness. EJ Sarmento's mAMP monos are $1.800/pr. Gato Audio's all-in-one DIA-250 is €3.250. Merrill Audio's Hypex-based Thor monos get $4.000/pr. Here and in-between there's plenty of power and refinement to be had without overspending. Mola Mola does push the other direction. But they mean to recoup significant Ncore R&D investment funds. And—or so one imagines at least—they also wouldn't mind to simultaneously move up class D's general perception. Here SPEC sides with Bruno Putzeys. The latter has both name and track record. At least in the West Shirokazu Yazaki has neither. Yet. Being a merely 60wpc class D integrated with a very strange though optional remote makes the RSA-M3EX unapologetically pricey. But if you want what it does—mimic valve sound to this extent whilst throwing in modern power efficiency which SET-ish class A transistor amps certainly don't—then this sober nearly laboratory-named Japanese brand could be the top game in town and play smack in the heart of your most desirable district. In the end it reiterates a hifi leitmotif. It's not topology or parts choices. It's the designer's clear auditory vision which becomes the core determinant over the final outcome. That's what bends parts and topologies to its will. Vision is key then. Taken to heart, it becomes clear that class D couldn't be exempt from this rule. If Yazaki-San's results surprise us, it's only because none before have endeavored to bend switching transistors quite so far in this direction. Henceforth SPEC marks that spot...
Quality of packing: Very good.
Reusability of packing: Many times.
Ease of unpacking/repacking: A cinch.
Condition of component received: Flawless.
Completeness of delivery: Perfect.
Human interactions: Good.
Pricing: High.
Final comments & suggestions: The remote control is a very dear €900/$1.200 option. Because the master volume isn't motorized, the wand can only adjust the master setting across a narrow window plus a steep mute. It doesn't afford control over the entire volume range like normal remotes. Calling it functionally crippled isn't unfair. In its 'power is cheap' market segment, SPEC's 60wpc class D power rating plus unapologetically high price march to a very different drummer. Meanwhile the lack of pre-out eliminates line-level subwoofer hookup. The main-in feature (volume control bypass) sets the amp to a fixed 20dB gain. Unfortunately this proved very noisy in junction with a Nagra Jazz preamp even with the latter set to 0dB voltage gain (this wasn't a ground loop but power-supply noise from the amp). This review thus concentrated exclusively on integrated use.
SPEC Corp. website