Esoteric A-03 Brochure

A-03 MAIN SPECIFICATIONS

General

Power supply AC 230 V, 50 Hz / AC 120 V, 60 Hz / AC 220 V, 60 Hz

Power consumption 400 W

External dimensions (W x H x D) 445 x 220 x 430 mm (17 1/2” x 8 5/8“ x 17”)

Weight 38 kg (84 lb)

Allowable operating temperature +10 ˚C to +30 ˚C (+50 ˚F to +86 ˚F)

Allowable operating humidity 5 % to 85 % (no dew condensation)

Allowable storage temperature - 20 ˚C to + 55 ˚C ( -4 ˚F to 12 ˚F )

Amplifier Section
Rated output power STEREO : 50 W + 50 W (1 kHz, 8 Ω) / 100 W + 100 W (1 kHz, 4 Ω)
BTL : 200 W (1 kHz, 8 Ω) / 330 W (1 kHz, 4 Ω)
Maximum useful output power STEREO : 77 W + 77 W (1 kHz, 8 Ω ) / 127 W + 127 W (1 kHz, 4 Ω)
BTL : 270 W (1 kHz, 8 Ω) / 400 W (1 kHz, 4 Ω)
Frequency response 5 Hz to 100 kHz (1 W, 8 Ω +0/ -1.2 dB)

Signal-to-noise ratio more than 117 dB
Total harmonic distortion 0.009 % (1 kHz, rated output, 8 Ω)
Minimum allowable speaker impedance STERE O: 4 Ω / BTL: 4 Ω
Warranted range for Class A amplification 50 W + 5 0 W (1 kHz, 8 Ω)
Input sensitivity (rated output) RCA (STEREO): 0.76 Vrms/50 W (8 Ω) / XLR (STEREO): 1.56 Vrms/50 W (8 Ω)
RCA (BTL): 1.62 Vrms/200 W (8 Ω) / XLR (BTL): 2.35 Vrms/200 W (8 Ω)
Input impedance 50 W + 50 W (8 Ω) / RCA: 150 kΩ / XLR: 320 kΩ

Gain RCA (STEREO): 28.4 dB

Accessories
Power cord x 1
Felt pads x 4
Power plug support bracket x 1
Screw for the power plug support bracket x 2
Owner's manual x 1
Warranty card x 1

• Design and specifications are subject to change without notice.

• Weight and dimensions are approximate.

• Illustrations may differ slightly from production models.

• This product is available in three different power supply variations shown
in the chart above. Make sure that the voltage shown on the rear panel
matches the AC line voltage in your area.

• The shape of the AC inlet and plug of the supplied power cord depends
on the voltage rating and destination country.

Please note that Esoteric products are available at limited distributors in respective countries. “Esoteric“is a trademark of TEAC
Corporation. All other brand or product names are trademarks or registered trademarks of their respective holders. ©2008 TEAC
Corporation. All Rights Reserved. All text, images, graphics and other materials on this catalogue are subject to the copyright and other
intellectual property rights of TEAC Corporation.
These materials shall not directly or indirectly be published, reproduced, modified or distributed in any medium. Design and specifications
are subject to change without notice.

PRINTED IN JAPAN 1208L05•TECD-0081

ESOTERIC COMPANY

1-47 Ochiai, Tama-shi, Tokyo 206-8530, Japan
Fax: [phone]

www.esteric.jp
www.teac.com/esoteric/

CLASS A STEREO POWER AMPLIFIER

English version

Building on the "State-of-the-art" technology, and uncompromising design behind ESOTERIC’s Master Sound Works Category

As you have never experienced it before,
the vivid colors of live music!

The grandeur of a Stradivarius; the clarity of a Steinway. The original
master tapes record each and every part of the music’s essence,
ranging from the fine flavor of individual sounds, or the beauty of a
symphony when those sounds are richly blended, to the ambience
of the concert hall and the enthusiasm of the audience.

ESOTERIC’s Master Sound Works concept pursues the vivid
reproduction of these elements. Born of ESOTERIC’s years of
experience in the development of state-of-the-art technology, this is
our latest evolution in sound quality: the Class A Stereo Power
Amplifier A-03. An elegant figure with enormous potential ----its
beautiful presence and exceptional output heralds the cutting edge
of audio amplification.
In the A-03, you encounter vivid sounds of unprecedented intensity,
bringing you an even more intimate relationship with your music.

CLASS A STEREO POWER AMPLIFIER A-03

Following the L/R dual mono concept to maximize
the purity of music

The A-03's superior channel separation, stable orientation, and depth of sound, will
make you feel as though separate monaural amplifiers were used for each channel.
This model employs dedicated dual mono technology that established Esoteric's
reputation for high-end design implementation. Equipped with independent power
sections featuring dedicated toroidal transformers for the left and right channels, this
amplifier also boasts enhanced mechanical strength and rigidity. Separate dedicated
compartments for the power transformer, the power circuits and the voltage and
current amplifier stages, all help to prevent electrical interference between
components.

Rapid, generous power supply
from separate high-capacity toroidal transformers

Dramatic transitions between sounds, each of which is injected with life by the
A-03's power supply capacity, directly arouse musical emotion. The power section of
the current amplifier stage---which drives the speakers---features independent,
large volume toroidal transformers, mounted on the left and right channels. This
enhances the amplifier's ability to supply current to each channel's speakers, while
preventing interference between the channels. By using an independent transformer
and power circuit for the voltage amplifier stage, which drives the current amplifier
stage, the effect of variations in the voltage is suppressed and the current amplifier
receives a stable power supply. Separating each circuit block into power circuits and
providing independent transformers reduces cross channel interference and enables
both robustness and a delicacy of expression within the music.

Pure "Class A" amplifier circuits to follow
every motion of the recorded material.

The performance capability to beautifully reproduce an outstanding musical climax,
or a nuance of simple acoustic delicacy, is one of the most important core qualities
in an audio amplifier. A pure class A implementation with low distortion and high
linearity is used for the amplifier circuit. This design always ensures an idling current
that can output a minimum of 50 watts RMS with an 8 ohm load. This, provides
excellent responsiveness for sudden bursts of high volume demand, as well as high
purity of expression. Large transistors with a current supply ability of 17 amps. for
continuous output, and 34 amps. for sudden bursts of high output, are used for the
current amplifier stage. Five of these transistors are mounted in a parallel push-pull
configuration for each channel, driving all speakers without compromise.

Usable as a monaural power amplifier
with bridged ("BTL"), connection

By using this product as a monaural power amplifier in bridged (BTL), mode, a
minimum output of 200 watts at 8 ohms can be achieved.

Obsessive use of high grade components everywhere

We have gone to extremes to use the highest quality components to maintain signal
clairity and minimize transmission loss. For connection terminals, the amplifier uses
the XLR input terminal---which is highly reliable and provides excellent
contact---along with ESOTERIC's original RCA input terminal. In addition, the WBT
nextgen; WBT-0710Cu speaker terminals have conductor cores of pure copper with
gold plating to achieve high conductivity and low resistance. On top of this, we have
used ultra high grade components such as an electrolytic capacitor and a high
frequency/low impedance transistor. These components were selected based on
property examination and trial listening. It is an Esoteric requirement that all critical
components undergo exhaustive listening tests before any final section is made.

A highly rigid structure to prevent circuit interference
and suppress resonance

The A-03 features a highly rigid body construction that surpasses a great number of
power amplifiers. The amplifier's mass of about 38 kg (84 lbs.) presages excellent
musical purity protected by thick steel. The internal circuit components are
separated into dedicated inner compartments for each circuit, partitioned by 2 mm
steel walls. Combined with a 5 mm steel bottom chassis, interference between
circuits is prevented and the adverse effects of resonance caused by internal and
external vibrations are minimized. Also, the unique chilled steel pinpoint feet provide
a very strong four-point support system for the heavyweight housing.

ESOTERIC's proprietary design generates
a beautiful sound space

If audio equipment is your passion, it must be beautiful. ESOTERIC's proprietary
high-end orientation and noise isolation provides the A-03 with a smart and practical
presence. A combination of blast finishing and short scratch finishing on the 20 mm
thick aluminum panels create a beautiful contrast. With its elegant rounded form and
large heat sink, processed from symmetrically-placed black alumite, the A-03
contributes to an elegant audio space, creating a sense of beautiful integration with
ESOTERIC's other high end products.

Now equipped with warm-up mode

This function enables the device to be warmed up to play audio, while reducing
electric power consumption (As compared to normal operation). At warm-up mode:
power consumption of 220 watts (a reduction of about 45%) is achieved.

MASTER SOUND WORKS

Large toroidal transformer
(Voltage amplification stage)

Large output transistor / Schottky barrier diode
(Current amplification stage)

Large heat sink finished in black alumite