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ESOTERIC A-100 Vacuum Tube Stereo Power Amplifier
A-100 Vacuum Tube Stereo Power Amplifier
So finally you can hear the true sound of original master tapes. 
It is the moment you've been waiting for. You can see the sound, feel the sound, and experience the sound. 
That's the quality of Master Sound Works amplification by ESOTERIC.

The Absolute Sound “2011 Editor's Choice Award”    The Absolute Sound “2011 Editor's Choice Award”
The Absolute Sound “2009 Product of the Year Award”    The Absolute Sound “2009 Product of the Year Award”
The Absolute Sound “2009 Golden Ear Award”    The Absolute Sound “2009 Golden Ear Award”
  • Ongen Publishing “Visual Grand-Prix 2011 Summer” Pure Audio Grand-Prix
    vacuum tube amplifier category winner (above ¥1,000,000)

- Master Sound Works -

A100 Master Sound Works The moment you hear this vivid sound, something you've never experienced before, you'll realize that the world of music and specialty audio systems has taken a great leap forward.

Master Sound Works ("MSW") is the result of over twenty years' accumulation of high-end technologies. MSW represents a further revolution in reference quality sound, as developed and implemented by ESOTERIC.

The overwhelming musical expression provided by the ESOTERIC MSW amplifier, a mega-masterpiece in its own right and the driving force of the series sets it apart from all conventional amplifiers.

Original master tapes faithfully record each and every piece of information within a work of music, ranging from the dense layers of strings, the roaring sound of a brass section, and the witty phrasing of jazz vocals, to the enthusiasm of an audience and the ambience filling the concert hall. By faithfully extracting and reproducing such a large amount of information, ESOTERIC can generate a feeling of realism that you have never experienced before. Confidence in this belief is what motivated ESOTERIC-a long-time developer of magnetic tape recording-to invest a vast amount of R&D, time and effort, all of which culminated in the A-100 amplifier. The A-100 is a product that perfectly reproduces the power and beauty contained within original master tapes and traditional digital masters.

ESOTERIC MSW amplifier series sets a new benchmark for amplifiers that emphasize rich and compelling music. Its natural and accurate sound bursts forward with an energy that simply mesmerizes the listener. This amplifier redefines the sound of SACD/CD and other analog or digital sources. No amount of rhetoric can fully describe the MSW sound; you have to actually experience the dramatically vivid colors and soundstage of the music it reproduces.

The cutting-edge benchmark the A-100 represents, includes proprietary technology with outstanding quality

The A-100 offers amazingly dynamic and lavishly delicate sound.
From its overall construction to its power supply, internal circuits, and individual parts and components, this stereo tube power amplifier incorporates leading-edge sound technology. This amplifier embodies ESOTERIC's attention to detail and determination to realize a definitive benchmark that will last forever.

The knowledge, wisdom, and expertise behind ESOTERIC's mastery of the essence of tubes

The A-100 delivers levels of musical expression never before available, exerting overwhelming potential provided by its directly-coupled three-stage circuit, an active bias circuit and a custom output transformer incorporating a 2nd order coil of silver-plated copper foil.

Directly-coupled triple stages

The DC voltage control circuit ensures stable operation of the directly-coupled triple stages (voltage amplification stage, cathode follower stage, and output stage), achieving a truly involving acoustic expression and an extremely natural warmth from the A-100.

Unique active bias circuit

The A-100 features a unique and advanced active bias circuit. This circuit compensates the bias voltage supplied to the output stage, detecting the cathode current and the driving level. High linearity and superior performance of the output stage is achieved by optimal bias voltage control from this new design.

Custom output transformer

foil The A-100 features a newly designed custom output power transformer achieving highly delicate and precise musicality. The amplifier uses specially treated dual layer foil (copper and silver), as the 2nd order coil. This design provides very tight coupling properties between the 1st order coil.

DC powered tube heater

All tubes except the KT-88 are DC heated. Hum noise is greatly reduced by this heater design.

Stabilized power supplies

All stages except the KT-88 stage are powered by fully stabilized power supplies. The A-100 reproduces an exceptionally deep and finely detailed sound stage using this innovative power supply design.

Mechanical chassis construction

Power supply and output transformers are held by an extremely rigid 'H' structure and circuit components reside in a block configuration surrounding this mainframe design. The massive chassis construction keeps the unit from unwanted vibrations and induced noise between circuit components.

Input selector / volume attenuator

The A-100 is designed for pure power amplification but it also works as an integrated amplifier by selection from an operating switch on the rear panel. This switch activates an input selector (RCA ×3 / XLR ×1), and includes a very high quality volume attenuator plus system remote control.

Two bias modes

The A-100 has two bias modes (A or B), selectable from a back panel switch. B mode is for a normal setting, and A mode (slightly reduced bias voltage), is for slightly finer sound depending on other component within the system. Often B mode might be selected for classical music but these decisions are totally subjective to the user.

High grade parts selection

RCA Jac RCA input terminals are highly reliable WBT-0201. The speaker terminals are WBT-0710Cu, the latest version of WBT terminals, incorporating pure copper conductor material for high signal purity and ultra-low terminal resistance. Signal loss is kept to a minimum with the use of these high grade audiophile connections.

Remote controller

A remote control with illuminated keys for integrated amplifier operation is included.

Output power Minimum 45W+45W (1KHz, 4ohms/8ohms)
Frequency response 20Hz to 60kHz (at 1W, 8ohms, +1/-3dB)
S/N ratio more than 98dB (JEITA)
Input sensitivity 400mVrms/45W (8ohms)
Input impedance 10kohms (Line in), 1Mohms (Direct in)
Input terminals RCA ×3
XLR ×1
Output terminals WBT-0710Cu pole terminals ×1 pair (4ohms/8ohms)
Tubes First stage: 12AT7 ×2
Drive stage: 12AU7 ×4
Bottom stage: KT88 ×4
General Power supply AC 230V 50Hz
AC 120V 60Hz
Power consumption 200W
External dimensions (W×H×D) 382×252×486 mm
(15-1/16×9-7/8×19-1/16 ")
Weight 40kg (88lbs)
- 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-100 A-100 A-100
A-100 A-100 A-100

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