“We will deliver the excitement of real sound

To music lovers, to convey the impression that never previously experienced.
Real Sound Amplifier RSA-F1 has a natural and beautiful tone of a tube-amplifier and the driving power of semiconductor one. This is high-quality new generation of high-performance PWM digital amplifier system.
Immersive concert, the sound of the instrument, breathing artist's impression provides a real sound of music brings.

Key Features of RSA-F1

1.A high performance power amplifier with a highly accurate PWM switching devices

By employing a newly developed power MOSFET in the power stage, generated noise is minimal and highly accurate and ideal PWM switching is achieved. Furthermore, a high-voltage gate driver IC with excellent time-axis control is employed in the driver stage to maximize the features of the power stage MOSFET. These devices prevent the noisiness in the high frequencies that is common with traditional digital amplifiers. Furthermore, excellent this gate driver and the power MOSFET performance ensures quality damping, even in the mid to low-range. This means a lively and dynamic sound, even from speakers with poor efficiency.

2.High quality sound supported by a power source with excellent supply performance

In order to maximize the potential of the unprecedented high efficiency of this amplifier (power utilization at maximum output: 96%), we employed classical plus/minus power source composed of minimal numbers of component that uses capacitor input-type bridge rectification. Our commitment to the acoustic quality of each individual part means that the instantaneous supply performance and the high quality power supply are directly related to the supreme sound quality of RSA-F1.

  • Rectifier
    A newly developed Ultrafast Soft-recovery diodes designed for high voltage and current are employed. This minimizes diode rectifier noise, which can negatively affect sound quality, and achieves clean and powerful sound across the entire range.
  • Power supply capacitors
    The main electrolytic capacitors used were developed in conjunction with a Japanese capacitor manufacturer and were specially designed for our RSA-F1. Furthermore, by connecting the best quality capacitors for high voltage signal use ( your paper/oil capacitor) in parallel, mid to high-range equivalent series resistance (ESR) is improved, resulting in a smooth and beautiful sound that achieves balance over the upper and middle ranges to the ultra-low range.
  • Transformers
    High-capacity R-core transformers are employed. Because the unnecessary leakage of magnetic flux is very low, responsiveness to instantaneous high voltage is excellent, realizing high speed sound with excellent rise.

Power efficiency of PWM switching device

Ultrafast Soft-recovery diode

Audio Electrolytic capacitor

3.A low-pass filter determines the sound quality at the final stage of the amplifier

Special ordered capacitor

The capacitors used have excellent high frequency characteristics and environmental dependability and were used in previous times for professional vacuum-tube equipments. Their material is close to natural and provides excellent musical sound. The many capacitors used in the low-pass filter and the snubber circuit of RSA-F1 are ordered specially to a part manufacturer that supplies the American aerospace industry and made to meet MIL standards.

4.Wooden base-chassis and insulators to realize rich, instrument-like sound

Joint development: Oak Village Corporation

In an unusual endeavor for an audio amplifier, natural wood was used for the base chassis and insulators.

  • Base-chassis
    A solid laminated panel of European spruce from Austria was used for the under-base. Spruce has long been used for the top plate of stringed instruments and the soundboard of pianos, and is known as a material with excellent sound quality that provides quick vibration transmission and moderate dampening. The combination of this material with the rigid steel chassis produces a rich pleasant sound.
  • Insulators
    The three insulators combine pure painted maple from Hokkaido, Japan and hickory from North America. Maple has excellent strength and is used in combination with spruce for the sides and backs of stringed instruments. Hickory is a hard material that absorbs impact well and is used for drumsticks for example. The maple and hickory insulators moderate the vibrancy of the spruce material and help provide rich musicality.
5.All high quality parts

High quality parts were selected so the RSA-F1 provides continued enjoyment over its long life. Parts necessary for high quality sound were carefully selected and employed, including a high-capacity power switch with a locking mechanism, a selector and a custom volume with excellent feel and high reliability, rugged pure copper speaker terminals, and RCA input jacks and XLR terminals plated with expensive rhodium.

Precision power switch with lock function

Rigid pure copper speaker terminal

Block diagram

Specification (Japanese model)

Maximum Power Output 60Wx2(8Ω), 80Wx2(6Ω), 120Wx2(4Ω)
Frequency Response 10Hz-30KHz±1dB(6Ω,1W)
Total Harmonic Distortion 0.02%(1KHz, 80% power output level)
Input Sensitivity/Gain 300mVrms, 37.3dB
(Maximum volume, 6Ω, 1KHz)
Input terminals RCA input : 3
Balanced XLR input : 1
Speaker terminals 1(Left/Right)
Power Requirement 100V, 50/60Hz
Power consumption 215W(8Ω, 100Hz)
Dimensions 450mm(W) x 130mm(H) x 422mm(D)
Weight 20Kg

Specifications and design subject to modification without notice.

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