S05

About the S05

The Esoteric S-05 is a high-end Class-A stereo power amplifier designed to express music's unique tonal qualities with exceptional purity and dynamic range. It incorporates many development results from Esoteric's flagship Grandioso M1X monoblock amplifier, featuring a simple and straight circuit design concept focused on minimal circuitry and maximum output. The amplifier uses dual monaural construction in all stages, including the power smoothing circuit, to ensure excellent channel separation. It employs Esoteric's proprietary ES-Link Analog current signal transmission for high power and fidelity. The power stage features a high-capacity bipolar transistor 3-parallel push-pull configuration for instantaneous response, powered by a large 940VA EI core power transformer and Grandioso-grade custom block capacitors (10,000μF × 4 per channel). The input stage is a highly stable balanced amplifier resistant to common mode noise. The amplifier supports two modes: BTL drive for high output and bi-amp drive for pure sound from multi-way speakers. It includes DC trigger for sequential power on/off with compatible devices, a semi-floating top panel, specially designed isolation feet to reduce mechanical stress, and a uniquely shaped heat sink to minimize resonance. The S-05 delivers 30W + 30W into 8Ω in Class-A operation, 60W + 60W into 4Ω, and 120W in BTL mode at 8Ω. It supports speaker impedances from 4Ω to 16Ω (8Ω to 16Ω in BTL mode). The frequency response ranges from 5Hz to 100kHz, with a signal-to-noise ratio of 102dB (IHF-A, XLR) and total harmonic distortion of 0.007% at 1kHz, 8Ω, 30W. Dimensions are 445mm (W) × 191mm (H) × 444mm (D), weighing 30.7 kg. Accessories include an instruction manual, power cable, and original box.