Yamamoto Sound Craft AT-03-1A Highest Quality Attenuator Unit

In addition to the overwhelming amount of information and high-frequency reproduction unique to passive attenuators, it also has a soft and warm tone. It has a light, light sound with no shortage of bass and stretch, delicate, bright and comfortable

The fewer circuits through which music signals pass, making the sound fresher and the sound quality can be improved. The attenuator section of the AT-03-1A and AT-03-3A uses an L-shaped volume adjustment function that switches between 28-point resistors with a switch. The L-pad type has only two resistors that enter the signal source, minimizing the sound quality of the resistor. The loss caused by passing resistors is minimized by the adoption of surface-mount resistors, and almost no noise is generated when switching contacts. The step interval for each switch point can be adjusted in 2dB steps from 0dB to -38dB, allowing for fine adjustments. The minimum volume can be reduced to -65dB, allowing for any level adjustment. The left and right level deviations when setting the volume for each volume are essentially within 0.2dB, and we have managed to keep the difference between the left and right levels, which is a weakness of continuous volume units, so small that it can be ignored.

The impedance is 50kΩ, making it an impedance that can be connected to any device. The volume adjustment switch and input switching switch for this unit are the 45SD type made by Seiden Co., Ltd., which has a reputation for improving reliability and ease of use. After numerous tests, the resistor in the volume control section uses a 1W type surface mount resistor from DALE, a US company. For the internal wiring of this machine, all wires were made of high purity 6N single wire with a diameter of 1.2mm. The wire is used in a Teflon tube, which has the highest insulation properties.

Perhaps thanks to the extremely simple structure, the sound was smooth. However, the tone and range are soft and warm, and gentle tones with a center of gravity in the midrange, which are similar to other Yamamoto Acoustic products. The piano has a round sound that gives off a sense of the warmth of wood, and the violin and classical guitars also have wood-like warmth. The timpanies and basses have moderate tenacity and stretch, and have a light tone that doesn't look too heavy. When natural sounds are reproduced, the sounds of waves, birds chirping, and the sounds of horned horned squeals are mellow and pleasant, yet with the fine details. The audio volume is slightly lower than that of Am Transformer or Phasemation.