Yamamoto Sound Crafts A-010 VT-52 Single Stereo Amplifier

The VT-52 has been passed down as a hidden gem among enthusiasts as a triode with excellent sound quality. It is no exaggeration to say that the VT-52, which has been enhanced for use with military transmitters, has the highest level of sound quality among the many triodes. The A-010 was designed to maximize the performance of the VT-52.

The A-010 has an appearance that uses Muku wood luxuriously. Four 80 rectifier pipes are used, and a luxurious power supply of one rectifier per tube is constructed. Mutual interference between power supply parts is eliminated, and the response speed of the power supply is also increased.
The A-010 uses only a film capacitor with a small value of only 2 μF in the driver tube to construct the input capacitor of this 80 rectifier tube, and uses a high-performance current regulator from Ichthys of the United States to provide a clear and excellent response speed. The choke coil in the output circuit is eliminated to form a filter circuit using only RC, and the configuration of these power supply parts improves the operating speed of the amplifier itself, resulting in a clearer sound with a sense of speed.

The A-010 uses a high-performance pentode C3m made in Germany as the driver tube. With a guaranteed lifespan of 10,000 hours, you can expect long-term stable use.
The heater circuit of the C3m and VT-52 vacuum tubes uses DC ignition with double-wave rectification to minimize noise, and a constant current circuit using Ichthys's high-performance MOS-FET to create a clean and fast response heater power supply. The output transformer is a custom-made 100 micron-thick core material with Teflon insulating paper coiled around it to improve sound quality.
The capacitors and resistors used are carefully selected from all over the world with the best sound quality selected through auditioning. The output terminal is machined with large gold plating and is compatible with banana plugs.

Even if the sound source is nearly half a century old, it has a powerful reproduction power, and there is not the slightest hint of harsh parts or cheesy sounds. The vocals make you feel as raw as if you were singing in front of you. Without compromising the dignity of the accompaniment, only the vocals are brought to the forefront, and the accompaniment seems to skillfully highlight the main singing. The speaker terminal is only an 8Ω output terminal, but there is nothing wrong with using 4Ω or 16Ω speakers. However, in either case, the maximum power is reduced. If the maximum output is 8W, the output will be about 4-6W.

When I put on the classical "The Seven Deadly Sins" by Weil, the rawness and sex appeal of Gisela Mai makes me feel as if she is singing in front of me. Even though it is a sound source that was taken nearly half a century ago, it is as if the atmosphere of that time was sent to the room together. While listening to the powerful reproduction of Mai's voice in front of the speakers, there is not the slightest hint of harshness or cheesy sound. In addition to the ability of the VT-52 ball, the certainty of Yamamoto Acoustic Crafts' construction seems to contribute greatly to its expression.
Jazz listens to Georges Patchinsky's Pleasance. I was surprised to hear the familiar software ringing as if I had woken up again. I wonder if the piano was so glossy, if the wood bass was so bouncy, if the drums were so rhythmic. It is a wonderful expression that makes it clear that the performer is genuinely enjoying the music.
For pop music, I listened to Emi Fujita's "Chamomile Smile". Like the classics, this one also gave the diva a vivid feeling as if she had been invited to the room. This kind of expression is not something that can be easily experienced with other amps. As is often the case with well-made tube amps, when you listen to the vocals, only the vocals come forward without degrading the quality of the accompaniment, and the accompaniment skillfully emphasizes the main singing. For those who want to listen to songs, it will be an amp that you will not be able to let go of once you listen to it.
*Excerpt from Analog magazine