Yamamoto Sound Craft New A-08SS "45" Single Stereo Amplifier

The model number A-08SS is a major evolution from the previous A-08S.The superiority of sound quality, which is a characteristic of the old model, has also been further improved in the new A-08SS. Although its output was small, the A-08S boasted sound quality comparable to that of a top-of-the-line 300B amplifier. This excellent characteristic is still alive and well in the new A-08SS. It is designed to be combined with high-efficiency speakers to bring out the best sound quality. The basic circuit configuration is the same as that of Western Electric's 717A driver tube and 45 vacuum tube output stage, but the most distinctive feature of the A-08SS is that all the components used have been reviewed to improve the quality of resistors and capacitors to the utmost limit.

On the A-08SSA power transformer that uses a cut core with excellent regulation inherited from the old model, an output transformer that uses a 100μ thick Hi-B cut core, and a cut core are also used for choke coils. In particular, the output transformer uses a fluororesin material with a low dielectric constant as the insulating paper for the coil to improve sound quality.

The chassis is made of a wood-based composite material called laminated reinforced wood, which is made by impregnating a thin veneer of cherry wood with excellent insulating properties and heat-molding it at high pressure. It has the same properties as phenolic resin in insulation, and its strength is stronger than that of phenolic resin. Externally, it looks the same as wood, but its properties are much better. The chassis made of insulators isIt prevents the effects of eddy currents inside the amplifier, and the high-strength chassis suppresses the resonance and squeaking of vacuum tubes and components, contributing to high sound quality.

The vacuum tube socket uses a high-quality in-house socket that combines fluoropolymer material with excellent insulation performance and phosphor bronze socket pins.

The best feature of the A-08SS is that all the components used have been reviewed to improve the quality of resistors and capacitors to the utmost limit. The circuit part of the amplifier, which used to use a chemical capacitor, has been changed to a high-quality film capacitor in an ebony case. With this change, the sound quality is clearer and richer.

In addition, the resistors have also been significantly upgraded. In the old model, wire wound resistors and metal film resistors were used, but in the new model, we have changed to surface-mount thin-film resistors with high precision and high sound quality.The main resistors of all stages are surface-mount thin-film resistors manufactured by Vishay of the United States, which has excellent characteristics, to improve the sound quality.The accuracy of resistors used in ordinary tube amplifiers is 1%~5%, but Vishay's thin-film resistors have a resistance error of 0.1% and a temperature coefficient of 5PPM~10PPM. High QualityThe resistor reduces the noise of the amplifier and greatly reduces the residual noise caused by hearing, so the A-08SS achieves high sound quality and provides a purer and more detailed sound.

There are no major changes in the basic design of the entire circuit, but in order to distinguish it from the old model in appearance, a stylish flange can be installed on the meter part. When the current value reaches about 60%~70% of the initial value, it is time to replace the output tube. The condition of the output tube can be seen visually, and the life of the vacuum tube can be visually confirmed.

The input terminals use machined chrome copper terminals for the outer conductor, round pin terminals machined from neighboring bronze for the internal pins, and top-of-the-line pin jacks with Teflon as insulation. The output terminals are machined pure copper and large Teflon-insulated terminals. A very thick speaker cable with a thickness of 8 mm can also be connected to this. 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.

The legs are carved out of African ebony, which has a reputation for having a beautiful sound. This African ebony wood is actually used for oboes and clarinets, and it has a beautiful sound, and is highly regarded as a setting base material for the company. The legs are fixed directly to the Komprite chassis for strength and resonance, and the overall weight is precisely supported.

The A-08SS is the ideal choice for music lovers and audiophiles. The outstanding sound quality inherited from the old A-08S is combined with new improvements to provide an exquisite listening experience. With the new A-08SS, we invite you to experience precious vintage sounds.