AURORASOUND - Experience Total Music Purity

AURORA SOUND is located in Yokohama, Japan and was established in 2010 by director and designer Shinobu Karaki, who has many years extensive experience in electronics and integrated circuits. He is an audiophile, passionate musician, and music teacher. These qualities make him the perfect person to design and develop high-end audio amplifiers.

His design philosophy combines innovative semiconductor technology with old valve technology to achieve outstanding performance and sound quality. Each unit is meticulously handcrafted, with final assembly made by ear, as well as physical and electrical measurements. The company’s philosophy is the building of audio equipment should be like a craftsman creating musical instruments; amplifiers should be works of art rather than mass-produced industrial designs.

HFSA-01 Integrated Amplifier

This is a hybrid stereo integrated amplifier that takes advantage of the advantages of both vacuum tubes and semiconductors. It has an output of 14W+14W using EL84 vacuum tubes and is equipped with bass and treble tone controls. The input section has a built-in phono equalizer, is compatible with MM cartridges, and has 3-channel RCA unbalanced input terminals.

Both sides of the front panel are accented with mahogany wood, creating a retro looking design.

Although it has a fairly conventional configuration, it has been developed as a product that creates superb sound quality and performance, incorporating the basic functions of an audio amplifier required for high-resolution digital sources to replaying analogue vinyl records.

The output vacuum tube EL84 is a pentode equivalent to the 6BQ5, and is operated in push-pull mode, resulting in an ultra-linear connection with excellent distortion and frequency characteristics. To drive the EL84, Aurora Sound have developed a unique circuit that uses a standard high-precision operational amplifier for audio, to configure a phase inversion circuit and to achieve an ideal push-pull drive.

The tone control section uses a CR type that is easy to hear, so you can adjust the rich bass or gentle treble to your liking, even with a small speaker.

The phono equalizer section corresponds to a general-purpose Moving Magnet cartridge, with excellent Signal to Noise characteristics due to Linear Technology semi-conductors.

The speaker output has terminals covering impedances from 4Ω to 8Ω, and it also has a headphone output.

The power supply section separates the vacuum tube circuit and the semiconductor circuit to prevent interference at any volume or frequency. The rectifier diodes are made of ROHM’s silicon carbide, which produces the least noise.

The output transformers and power transformers are domestically manufactured to order by Aurora Sound to match this circuit, and the resistors and capacitors are also carefully selected and of high quality.

Phono                                         Moving Magnet 40dB
Cartridge Load Impedance      4k Ohm
RIAA deviation                          +/- 1dB
RCA Unbalanced                      CD, Line 1, Line 2
Tone Control                             Bass +/- 12dB, Treble +/- 12dB>
Output                                       Maximum 14w – 14w 8 ohm load
Frequency response                10Hz – 40kHz -3dB, Tone flat
THD+N                                      0.08% 1kHz, 2w, A rated
SNR                                            93dB, Line In-Out
Various Functions                   Tone control Path, Direct Switch,                                                                         Stereo/Mono Switch, Headphone Output
Power Supply                          AC 240V 50Hz, Power Consumption 150w
Dimensions                              360mm(W) x 320mm(D) x 145mm(H)
Weight                                       10.3kg