The unique sensation of spaciousness, which arises when sound flows effortlessly and expansively, along with the authentic experience of a live performance, is only achievable when an amplifier possesses a substantial power reserve to effectively drive the speakers. To fulfill these criteria, Esoteric amplifiers are constructed using top-tier components and robust power supplies. Adhering to the design principles established for the flagship mono power amplifier M1 from the Grandioso series, the new Esoteric S-02 stereo model captures every detail of sound and conveys the full emotional depth of a live performance.
Speaker impedance can fluctuate significantly based on the frequency characteristics of the music being played. Rapid bass attacks place considerable demands on the amplifier, necessitating not only high continuous output power but also the ability to handle repeated signal peaks. If the power supply falls short in this regard, the music’s dynamics may be compromised. The Esoteric S-02 features a powerful power supply that can deliver an impressive 580W into 2 ohms and a nominal power of 145W into 8 ohms, demonstrating a linear relationship between output power and load, which enables it to reproduce the complete dynamic range of audio signals at any volume.
Great care was taken with the custom Esoteric S-02 power transformer, from the choice of materials for its EI core, to the cross-section of the magnetic core, and even its mounting on the chassis. This type of transformer is popular with audiophiles for its full-bodied, high-quality bass. To maintain the purity of the sound, this large 940VA transformer has separate secondary windings for the left and right channels and is firmly mounted on a rigid 5mm thick steel plate. Three parallel-connected 4700uF capacitors per channel reduce charge/discharge time and ensure a tight, fast sound. The power buses are laid with thick cables with crimp connectors to reduce impedance to the lowest possible level. To reduce output impedance to an absolute minimum, the designers used 9 thick buses in each channel for the power stages and eliminated the need for an inductor (coil) at the output.
Great care has been taken to simplify the circuit and expand its bandwidth, resulting in an exceptional damping factor of 1000. This ensures that even the large-diameter bass drivers receive precise damping for accurate sound reproduction, providing a sense of breadth across the entire frequency range – right down to the deepest bass. The input audio signal enters the Esoteric S-02 via balanced discrete buffer stages and is transmitted to the amplifier stages via a balanced low-impedance path. The outstanding dynamic range is ensured by a clean, noise-free signal, as well as the high sensitivity required to convey every nuance – from the musical crescendo to complete silence. Large bipolar LAPT (Linear Amplified Power Transistor) transistors, capable of delivering 17 amps continuously and up to 34 amps instantly in peaks, also have the wide bandwidth required for the highest tonal fidelity.
The LAPT transistors are arranged in a three-stage Darlington configuration with five parallel push-pull modules. The unique LIDSC (Low Impedance Drive Stage Coupling) driver stage coupling scheme used in the Esoteric S-02 reduces transient impedance and increases the ability to deliver high currents. This allows for the signal amplitude to be maximized within the available voltage from the power supply, reducing distortion, bringing the Esoteric S-02’s ability to drive loudspeakers closer to that of the top-of-the-line M1 monoblock.
The designers sought to make the amplifier circuit as simple as possible and thereby minimize the depth of overall negative feedback in order to achieve a natural and life-like sound. The voltage gain stage has a separate power supply with a small toroidal power transformer and stabilizer – for a radical improvement in the resolution of fine musical details.
The Esoteric S-02 uses highly reliable XLR and RCA input connectors, as well as speaker terminals from WBT in Germany, low-impedance electrolytic capacitors and transistors with excellent high-frequency characteristics. Traditional Esoteric two-tier chassis is divided into separate compartments by 2-mm steel sheets, while its lower level is made of 5-mm steel, and the front panel is made of thick aluminum. Four proprietary Esoteric point supports ensure the stability of the heavy case and the absence of resonances.
