The Yamamoto Sound Craft A-08 Stereo 45 SET Stereo Amplifier
Nuts & Bolts
My review unit arrived directly from Japan just as your own A-08 would if you ordered one from Brian. The following description and observations are pretty much what a paying customer would experience. The amplifier was nicely packed with an outer and inner cardboard shipping carton and Styrofoam inserts. Pulling out the latter revealed a nicely wrapped A-08 which I quickly peeled down to inspect - SET amplifiers generate a lot of excitement here at Jeff's Place.


I gawked over how beautiful the chassis was with its Japanese Cherry wood/resin composite plate, champagne transformer cover with Cherry/composite cheeks and solid African Ebony legs. The photographs just don't do justice. Take it from my eyes - the Yamamoto is gorgeous! I couldn't have pounded down the lust bumps with a hammer. Mr. Yamamoto says he designed the chassis not only to look but to sound good: He chose its Cherry wood/composite chassis and ebony legs because their sonic characteristics delivered a more natural tonal balance than other materials he experimented with.


The Yamamoto's use of a flat top plate with wooden legs -- most easily seen in the lower nude shot -- reminded me a lot of how my beloved Fi 2A3 monoblocks are constructed from a flat aluminum top plate with wooden legs. The Fi uses a matching aluminum skirt to keep prying fingers away from the innards, but the bottom is open so you have to exercise caution. The Yamamoto takes a more cautious approach by using a ventilated belly pan that conceals the innards. When you drop the pan, you are treated to a point-to-point hand-wired art show.


Check out those gorgeous Yamamoto Teflon sockets with their gold-plated brass hardware and the Dale resistors! The RCA connectors and speaker binding posts are CNC machined at Yamamoto and works of art as well.


The RCA sockets' outer barrels are made of chromium copper and then gold plated, with the inner pin contacts made of bronze encased with Teflon insulation. The speaker terminals are easily the nicest I've ever had the pleasure to use. They are made of pure gold-plated copper and terminated in large easy-to-use knurled knobs that accept spades or banana connectors.

The nude transformers towering above the Cherry plate are quite a sight both for their size -- huge for a 45 triode -- and their construction. There's a lot of iron in those cut-core high-B transformers. Damn, those are some big jugs! ('Jugs' is motorcyclenese for big-bore engine cylinders.) The trannies use in-house developed Teflon insulation paper and resin and all the performance ingredients of the transformers are trade secrets.

I unwrapped and unboxed the tube complement - 2 x RCA Cunningham NOS 45 tubes, 2 x 717A Raytheon pentode inputs, 1 x 5UG-4 rectifier. It's not often that one sees any amplifier this affordable arrive with new-old-stock tubes, let alone Cunninghams! This was the first time I'd ever seen the little mushroom-shaped 717As.

It is astonishing how an amplifier priced at $2250 could be supplied with solid ebony legs (think Shun Mook), custom Teflon tube sockets, custom connectors, premium internal parts, composite materials and NOS valves. From a parts-quality perspective, the Yamamoto A-08 stands in a class of its own in what has to be the SET audio bargain of the century! But how well does it play music and how good does it sound?


Listening Impressions
While the sound of different SET circuits varies even when the same type of output tube is used, there does remain a certain familiar characteristic to the tube types carried through differing circuit implementations. 845 tubes still sound like 845 tubes, 300B tubes still sound like 300B tubes, the 2A3 tube still sounds like a 2A3 and the 45 too has its own unique sound. And of course, they all have different power outputs: an 845 is good for about 20 watts, a 300B for about 8 or 9, a 2A3 for 3.5 watts and a 45 for between 1.5 and 2 watts. Fans devoted to different tube types for their sonic characteristics must match their available power to their speakers and also consider a system's overall sonics. In the end, it's about matching your system to your musical tastes; after all, you're the one who listens to it every day.


My former Cary 805C monoblocks with their 845 output tube had a warm and dark presentation with a gorgeously lush midrange and a relaxed billowing sense of space that produced impressive soundstaging. Audio pal Pete Riggle's hand-crafted Guilty Pleasure 845 integrated amplifier shares many of those same characteristics while being a completely different circuit design that matches the sonic signature of Pete's system to a T -- 'T' for 'triode', naturally -- and produces an exceptionally engaging presentation of the music.


300B amplifiers tend to have beautifully detailed, natural-sounding midranges and a powerful mid-bass that gives punchy pace & rhythm, a touch of fire-side warmth and a certain sense of tangibility that puts flesh and blood on musical bones. 45 tubes tend to be clean, refined, detailed & nuanced and give an airy and spacious presentation. 2A3 tubes tend to be half-way between 300Bs and 45s. They are more dynamic than 45s but less punchy in the mid-bass than 300B tubes. They aren't as airy and spacious sounding as 45s and 845s, but in my opinion produce more accurate instrumental and vocal timbres than either of them. 2A3s aren't as detailed and nuanced as a 45 but are the most evenly balanced triode across the frequency extremes - and that goes for all the tubes mentioned. Which one is best? The one that works best with your system to give you the sound you fancy.


Hangin' with Terry Cain in the City So Nice They Named it Twice: Walla Walla
"Hey Jeff, what say you we get together this weekend and finalize the plinth design for the Garrard 301 turntable project?" queried Terry Cain. "Sounds fun," said I, "and how about I bring along the Yamamoto 45 for a listen?" "Sounds great," quipped Terry, "I'd love to hear the little Yammy."


Terry had just gotten back to town after a successful showing at the Rocky Mountain Audio Fest and was still in recovery mode. It's an enormous amount of work just to attend CES to take pictures for my annual photo coverage for Rod's Audio Asylum and the inmates. I can't even imagine getting all the gear to a show, setting up a room, getting the room and system to sound good in a matter of hours and then demoing music for all the showgoers for three days straight. It's too much to even imagine! And Terry drove to Denver and back from Walla Walla. Mysteriously, all the gear you saw in Srajan's show coverage of his room fit into Terry's vintage Volvo wagon!

Terry's call came at just the right time. I'd just survived another grueling week at the office and was looking forward to a little stress relief playing oddio games and listening to some good tunes. On Sunday morning, I dragged my butt out of bed early and loaded up my diminutive Miata with the Yamamoto and a bag of audio goodies for the Garrard project. I made a quick stop at Starbucks to snag a couple of raspberry Danishes and a thermos full of Americanos (espresso diluted with a little water) to share with Terry. I quickly passed the hour's drive from the sunny desert-shrub steppe of Richland to the rolling vineyard country of Walla Walla where Cain & Cain's shop and listening room awaited. To give you an idea of what the Walla Walla countryside looks like, enjoy Leslie Cain's pastel on paper "Hay in the Pine Creek Bottom" that was on
display in a local gallery (as Terry's better half, Leslie is the first Cain in Cain & Cain). By the time I arrived, Terry already had the big Studio BEN ES double horns up and running with Josh Stippich's amazing Electonluv custom amplification artwork. Even the gorgeous Yamamoto looks mundane next to the otherworldly artwork of Josh! Let me tell you, they sound just as good as they look! Sources on Sunday included the excellent VRS Audio Systems audio computer for high performance digital duties and Terry's Teres Audio turntable for vinyl rites. Cabling was Cardas Golden Reference throughout.