New product announcement HFSA-01, Aurorasound Apr. 2023

Vacuum Tube Pre-Main Amplifier

HFSA-01

Aurorasound, New ProductHigh Fidelity Stereo Amplifier

Product Outline
HFSA-01 is a hybrid pre-main amplifier utilizing
the advantages of both vacuum tube andsemiconductor. The tube EL84 delivers 14W +14W power output. The model is equipped withbass and treble controls. The input stage has abuilt-in phono equalizer for MM-type cartridges,
along with 3-channels of RCA unbalanced input
terminals.

FeatureThe output vacuum tube EL84, a pentodeequivalent to 6BQ5, is operated in push- pullconfiguration delivering extremely low distortionand excellent frequency characteristics with ultralinear connections. The driver for EL84 is a wellknown Texas Instruments OPA604A, a highprecision audio Op-Amp. Aurorasound developed aperfect phase inverter circuit with OPA604A todrive the push-pull operation in the most ideal way.

This model accepts speakers with 4 Ω to 8 Ω
impedance. In addition, it has a headphone output.

The tone-control section employs a CR-type foreasy adjustments to achieve more rich bass andcomfortable treble to meet listeners’ sound taste
even with small-size speakers.
The phono equalizer uses Linear Technology’ssemiconductor to achieve an excellent S/Ncharacteristic with NF-type circuit configuration.
The power supply section is completely isolated
between the vacuum tube and semiconductor tocompletely eliminating any interferences regardlessof volume level and frequency range. The rectifier
is of the super low noise Rohm’s silicon carbide
diode.
The output transformer and power supply
transformer are custom designed by Aurorasound,and manufactured by a Japanese company. Thismodel employs carefully selected high-quality
capacitors and resisters, as well.

HFSA-01 is designed with orthodox configuration,
however, it fulfills the basic requirements such as
sound quality and overall performance for a wide
range source from high-resolution digital toanalogue records that any generation and age
demands.
The front panel is ornamented with Mahogany
wood on both sides to enhance the retro
appearance
producingaratherrelaxing
atmosphere for more enjoyable audio life.
Contact
Aurorasound Inc.
www.aurorasound.cjp
Tel +81-45-953-6708, Email: karaki@aurorasound.jp

www.aurorasound.jp

Sales start

April/30 , 2023
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New product announcement HFSA-01, Aurorasound April. 2023

Rear PanelInput
PHONOMMCDLINE-1
LINE-2
OutputSpeakers
8Ω4～6ΩIEC AC Inlet

InsideEL84
Tubes

Mahogany woodside fender

Seismic isolation forvacuum tubes protection

DALE wire wounded resistor
PPR metal foil audio graderesistor

ALPS volume pot

Nichikon Electrolytic Capacitor
WIMA film capacitors

ROHM Silicon carbide rectifier diodeTexas Instruments, Linear Technology
OPA604A, LT1028 OPAMP ICs

www.aurorasound.jp

Large size iron core transformers.
Aurorasound custom design

Solid aluminumfoot insulators

2New product announcement HFSA-01, Aurorasound April. 2023

Inside view

Block Diagram

HFSA-01 Block Diagram
NFB loop
Buffe AMP
MM phono

CD

RIAA
EQ

Volume
INPUT
Selector

EL84-push pull

Phase INV.

TONE

Speaker
Output+8ohm

BASS
TREBLE

Self BIAS
RC

LINE-1

4~6ohm-NINE-2
Headphone
out+BV+/-VccFrontend
Power Regulator

OutputPower Regulator
POWER Regulator Section

AC

Copy Right : AurorasoundSpecifications
Input

TONE Control
OutputFrequency response
THD+N
SNR
Functions
AC voltage
Size, Weight

www.aurorasound.jp

Phono-MM, Gain40dB,
Cartridge load resistance 47kΩ, RIAA +/-1ｄB
RCA unbalance、CD, LINE-1, LINE-2
BASS +/-12dB, TREBLE +/-12dB,
Max 14W + 14W at 8Ω speaker
10Hz ~ 40kHz, -3dB, Tone Flat
0.08％, 1kHz, 2W, A-weighted
93dB, LINE IN-OUT
TONE control pass DIRECT SW, Stereo/Mono, Headphones output
USA model AC120V, Europe/Asia model AC220V, 240VPower consumption 150W
W360 x D320 xH145mm max , 10.3kg

3New product announcement HFSA-01, Aurorasound April. 2023

www.aurorasound.jp

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