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ESOTERIC A-03 Stereo Power Amplifier
A-03 Stereo Power Amplifier
The vivid colors of live music, as you致e never experienced it before!

Stereo "Best Buy Component 2015"   Stereo "Best Buy Component 2015"
Power amplifier category (¥550,000 - 1,200,000)
Ongen Publishing "Visual Grand-Prix 2015"    Ongen Publishing "Visual Grand-Prix 2015 Summer"
Power amplifier category (below ¥1,000,000)

  • Stereo "Best Buy Component 2012"

Stereo Sound "2012-2013 Best Buy Components"   Stereo Sound "2012-2013 Best Buy Components"
Power amplifier (¥500,000 - ¥1,000,000)
Stereo Sound “2011-2012 Best Value Component”    Stereo Sound “2011-2012 Best Value Component”
Ongen Publishing “Visual Grand-Prix 2012” Pure Audio Grand-Prix    Ongen Publishing “Visual Grand-Prix 2012”
Pure Audio Grand-Prix

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 Stereo Power Amplifier A-03. An elegant figure with enormous potential - its beautiful presence 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.

Master Sound Works

Advanced power supply with dedicated L/R dual mono architecture L/R dual mono architecture

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.

Realizing the highest expression of purity with independently mounted high capacity toroidal transformers
High capacity toroidal transformers

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.

An amplifier circuit with wide range, high speed, and powerful drive

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 50watts RMS with an 8ohms 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 17amps. for continuous output, and 34amps. 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.

Can be used as a monaural power amplifier with a bridged connection

By using this product as a monaural power amplifier in bridged (BTL), mode, a minimum output of 200watts at 8ohms (1kHz, 8ohms) can be achieved.

Obsessive use of high grade components everywhere
rear A-03
electrolytic capacitor and a high frequency/low impedance transistor

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
A highly rigid structure

The A-03 features a highly rigid body construction that surpasses a great number of power amplifiers. The amplifier's mass of about 38kg presages excellent musical purity protected by thick steel. The internal circuit components are separated into dedicated inner compartments for each circuit, partitioned by 2mm steel walls. Combined with a 5mm 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 design forms a beautiful musical space

A combination of blast finishing and short scratch finishing on the 20mm thick aluminum panels create a beautiful contrast. With its elegant rounded form and large heat sink, processed from symmetrically-placed black alumite, the A-30 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 music, while reducing electric power consumption (As compared to normal operation). At warm-up mode: power consumption of 220watts (a reduction of about 45%)

Rated output power STEREO 50W+50W (8ohms)
100W+100W (4ohms)
BTL 200W (8ohms)
Maximum useful output power STEREO 77W+77W (8ohms)
127W+127W (4ohms)
Frequency response 5Hz to 100kHz (1W, 8ohms. +0/-1.2dB)
Signal-to-noise ratio more than 117dB
Total harmonic distortion 0.009% (1kHz, rated output, 8ohms)
Minimum allowable speaker impedance 4ohms
Input sensitivity (rated output) RCA (STEREO) 0.76Vrms (50W, 8ohms)
XLR (STEREO) 1.56Vrms (50W, 8ohms)
RCA (BTL) 1.62Vrms (200W, 8ohms)
XLR (BTL) 2.35Vrms (200W, 8ohms)
Input impedance RCA 150kohms
XLR 320kohms
Input terminal RCA ×1
XLR ×1
Output terminal Speaker terminal
Screw type (WBT-0710Cu) ×1
Ground terminal Large screw terminal
General Power supply AC 230V 50Hz
AC 120V 60Hz
AC 220V 60Hz
Power consumption 400W
External dimensions (W×H×D) 445×220×430 mm
(17 1/2×8 5/8×17)
Weight 38kg (84lb)
- Design and specifications are subject to change without notice.
- 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.

A-03 A-03 A-03
A-03 A-03 A-03

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