Esoteric F-01 Class A Integrated Amplifier

The Esoteric F-01 is a reference-grade Class A integrated amplifier designed to deliver the refinement of Esoteric’s flagship separates in a single, exceptionally engineered component. Drawing heavily from technologies developed for the Grandioso C1X preamplifier and S1X Class A power amplifier, the F-01 combines a fully balanced dual-mono preamplifier, powerful Class A amplification, advanced volume control, premium analog connectivity, and extensive system-upgrade capability.

Pure Class A Power

The F-01’s power amplifier section follows the circuit philosophy developed for the Grandioso S1X and delivers 30 watts per channel into 8 ohms in Class A.

Behind that seemingly modest rating is an exceptionally substantial power supply featuring a massive 940VA EI-core transformer, dual-monaural rectification and smoothing circuits, and Grandioso-grade custom capacitors. The design prioritizes current delivery, dynamics, control, and tonal richness rather than simply chasing higher output numbers.

Four 10,000μF capacitors per channel operate in a dual-mono parallel configuration to provide a stable supply of current during demanding musical passages.

Grandioso-Inspired Balanced Dual-Mono Preamplifier

Unlike many integrated amplifiers, the F-01 incorporates a preamplifier architecture designed to approach the performance of a dedicated separate component.

Its large-scale balanced dual-mono preamp incorporates technologies developed for the Grandioso C1X, with independent left and right signal paths and careful isolation of the audio, rectification, and control circuitry.

Ultra Fidelity Attenuator System

At the heart of the F-01 is Esoteric’s proprietary Ultra Fidelity Attenuator System, derived from the Grandioso C1X.

The UFA-1792 stepped attenuator provides exceptionally precise 0.1 dB adjustment across 1,120 steps, allowing remarkably smooth and accurate volume control while its high-voltage architecture is designed to maximize dynamic range and signal-to-noise performance.

ES-Link Analog

The F-01 includes three XLR inputs switchable between conventional balanced XLR and Esoteric ES-Link Analog.

ES-Link Analog uses Esoteric’s proprietary current-transmission architecture, designed to minimize the influence of interconnect impedance and preserve extremely small musical signals. The F-01 also provides both ES-Link Analog and XLR preamp outputs, allowing the technology to be used further through a compatible Esoteric system.

Fully Balanced Headphone Amplifier

Headphone listening receives the same serious engineering attention as the main amplifier.

The F-01 incorporates a fully balanced dual-mono headphone amplifier with both 4-pin XLR balanced and 6.3 mm unbalanced outputs. Balanced output reaches 600 mW into 32 ohms, while adjustable gain from 0 to +18 dB in 3 dB increments allows the amplifier to accommodate a wide range of headphones.

Dual-Mono MM/MC Phono Stage

Vinyl playback is integrated at a similarly high level. The built-in MM/MC phono preamplifier uses independent left and right circuits and independent channel power supplies for excellent channel separation.

This makes the F-01 a compelling centerpiece for systems combining reference digital playback with a high-performance turntable.

Precision 3-Band Tone Control

A balanced dual-mono Treble / Middle / Bass tone-control circuit provides precise adjustment without compromising the F-01's high-end design philosophy.

Adjustments can be stored independently for each source, with control available in fine 0.5 dB increments up to ±12 dB.

Exceptional Speaker Control

Esoteric has extensively reduced internal impedance throughout the amplifier, using 105μm copper circuit-board conductors, 1.0 mm high-purity OFC bus bars, ultra-thick internal cabling, and contactless MOSFET speaker-output switching.

The resulting damping factor of 500 gives the F-01 substantial control over demanding loudspeakers and large woofers, particularly in the lowest frequencies.

Reference Chassis Construction

At approximately 32 kg (70.5 lb), the F-01 has the physical construction expected of a reference separate amplifier.

Extensive aluminum construction, a semi-floating top panel, Esoteric’s patented isolation feet, and specially shaped heatsinks are all designed to control resonance and mechanical vibration while preserving the amplifier's musical openness.

Designed to Grow With Your System

The F-01 offers unusually extensive upgrade possibilities for an integrated amplifier.

An Esoteric S-05 Class A power amplifier can be connected through the XLR or ES-Link Analog pre-outs to create a multi-amplifier system. The optional PS-01F external power supply can also be added to further enhance the performance of the F-01's internal preamplifier.

Key Features

• 30W + 30W into 8Ω, Class A
• Balanced dual-mono preamplifier architecture
• Grandioso C1X and S1X-derived technologies
• Massive 940VA EI-core power transformer
• UFA-1792 Ultra Fidelity Attenuator
• 1,120 volume steps in 0.1 dB increments
• 3 × ES-Link Analog / XLR selectable inputs
• XLR and ES-Link Analog preamp outputs
• Fully balanced dual-mono headphone amplifier
• 4-pin XLR and 6.3 mm headphone outputs
• Built-in dual-mono MM/MC phono stage
• Balanced 3-band tone control
• Damping factor: 500
• Optional PS-01F external preamp power supply
• S-05 multi-amplifier expansion capability
• RS-232C and trigger control for system integration

The Grid HiFi Recommendation

The Esoteric F-01 is an outstanding choice for a reference two-channel system where the purity and musical character of Class A amplification are desired without moving to a full stack of separate components.

Speaker matching is especially important when selecting a Class A amplifier. Contact The Grid HiFi for expert advice on pairing the F-01 with the right loudspeakers, digital sources, turntables, cabling, and power components for your system and listening room.