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Transitioning from such a well-informed fine presentation to the legendary current-gen Western Electrics stepped down insight and finesse. This from someone who considers the Emission Labs solid-plate 45 the ultimate triode. I would add then that much here depends on the high-frequency chops of your system, from the source all the way to the speakers. I can easily envision how someone with a lesser system in this regard would conclude that the Czech valves are forward and harder. In Shigeki-San's amp, they're clearly not. But then, his amp was voiced around the Emission Labs valves for which Yamamoto now is the Japanese importer.


That being the case, the Western Electric despite reputation becomes somewhat of a compromise which doesn't take full advantage of the A-09S's greater bandwidth and current delivery from its rare driver tubes. Considering the high fee the Americans command, that's a delightful conclusion.

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But what if you prefer a more traditional 300B sound? How close does TJ's globe version come to the Western Electric? Very. I might give the WE the nod in the final tally -- on tone density particularly during complex passages -- but in my context, it was only a very small lead. What remains true for both tubes is that vis-à-vis the best of the Czechs, there's less amplitude down low; and the bass is a bit more rotund and less damped. The biggest difference however is in the treble and how the traditional rounded-off top end masks the true content of upper harmonics.

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Since music consists primarily of midrange, not isolated triangle decays, swirling cymbals and other upper-end noise makers, this loss of luster most overtly affects the vocal band. Put simply, it undermines the 'spark of life' energy that enlivens music from within. If scale, power and majesty are tied to the bass; finesse, brio and lightness of being live in the treble. On superb recordings with true -- or very deliberately doctored -- ambient information, that extra visibility of overtone spray and decay additionally informs subtle depth and inter-performer perceptions. Another welcome side effect is greater projection intensity at lower levels.


To reiterate, the modern triodes here actually make more tone than their traditional brethren because they include aspects the latter diminish. Thus a system deliberately voiced for what is commonly equated with the 300B sound will get more lit up and energetic, with more forward projection and robuster bass. Whether that will please the owner or not is a personal matter. Inserting a superior transistor amp like the Nelson Pass F5 or the Peter Daniel Patek SE for a reality check proves how regardless of what 300B is chosen, these triodes are not the transistors' equal in raw resolution. Be it noise or 2nd-order distortion intermodulation on more complex material, the 300Bs in single-ended zero NFB mode put stuff between and around the notes which the transistors remove. Very pleasant - but not as microscopically resolved.


Surprisingly, the amount of woofer damping particularly the Euro Audio Team and Emission Labs valves can exert on a benign but fully extended load like Franck Tchang's Tangos is not far behind the kind of transistors I had on hand. That part is quite shocking and an important reminder that LF impedance behavior is the more important determinant for triode happiness than voltage sensitivity. And Yamamoto's trick NOS drivers have abundant gain to play far louder on the same input voltage than the thrice as powerful FirstWatt F5.


Wrap 'er up
From the three 300B stereo amps in house -- Emillé, Woo and Yamamoto -- Shigeki-San's is my clear favorite. It comes closest to my 45 ideal but adds more balls and midrange richness; plus realistic drive to go far beyond what the A-08S' two watts could handle. While it takes about 20-30 minutes to come on song fully, it'll take any 300B made to allow its owner unusual liberty in rolling for flavor.


From all the 300Bs sampled, the two highest performers to these ears are Jozefina Krahulcová's EAT and Jac van der Walle's EML 300B XLS. They seem virtual stand-ins, with the Emission Labs slightly 'waftier', the EML a tad tauter. But that's splitting hairs. Both are exceptional. For drive and low-end control, the huge EML 5U4G rectifier is the ticket. Considering that EAT doesn't make one, it's perhaps not surprising that Shigeki-San settled on Emission Labs as the preferred current-production valve brand for his premium amplifier.


I acquired this amp on good faith, purely on the strength of my prior evidence - ownership of the A-08S and HA-02. The man from Japan whom I've never met yet didn't let me down. Again. His A-09S is a thoroughly modern, beautifully built, 'spring-cleaned' 300B SET that demonstrates with complete conviction how the antiquated concept of this triode is alive and well in 2008. If the Europeans manage to outlaw class A amplifiers for energy inefficiency as talk has it, you shouldn't wait too long. Get at least one premium example of the breed to last you through the dark days when class D or A/B will be the only amps allowed for public consumption. When I think premium but not silly money -- not trophy hifi but fairly priced kit of exceptional build quality, understated good looks, a solid track record, great reliability and endowed with that artisanal blessing -- Yamamoto's A-09S tops the charts in this category.
Quality of packing: Excellent.
Reusability of packing: Multiple times.
Ease of unpacking/repacking: Easy.
Condition of component received: Perfect.
Completeness of delivery: Power cord, owner's manual, tubes as per order.
Quality of owner's manual: Software translation from the Japanese.
Website comments: Relies on software-generated translations which are awkward and difficult to understand. Definitely could stand improvements if greater appeal for a non-Japanese audience was desired.
Human interactions: Always prompt and directly with the designer.
Pricing: As always with this brand, fair. You get what you pay for.
Final comments & suggestions: This amplifier's gain structure and drive potential, especially when fitted with EAT or EML 300Bs and EML's 5U4G rectifier, exceeds the norm to make it suitable for somewhat counter-intuitive loudspeakers. Benign LF load impedance behavior remains important for best performance but 90dB voltage sensitivity isn't too low at all even with a preamp of only 12dB of gain. In short, don't overlook this amp based on its 8wpc paper specs.

Yamamoto Sound Craft website