Feliks Audio – Bliss

Feliks Audio Bliss – Reference Electrostatic Headphone Amplifier

The Feliks Audio Bliss is a reference-grade electrostatic headphone amplifier that marks Feliks Audio’s first entry into the electrostatic domain. After more than four years of development, the Feliks Audio Bliss was officially unveiled in its final form at High End Munich 2025, where it received two Best of Show awards from Soundnews and Headfonia. Designed without compromise, the Feliks Audio Bliss represents the pinnacle of tube-based electrostatic amplification.

Ultimate Electrostatic Performance

Engineered to drive any electrostatic headphone, the Feliks Audio Blissdelivers exceptional transparency, dynamic range, and tonal realism. Its sound signature is natural yet authoritative, combining fine micro-detail with a vast, holographic soundstage. From classical and jazz to rock and electronic music, the Feliks Audio Bliss reproduces music with accuracy, control, and emotional depth.

Fully Tube-Based, Transformerless Class A Design

At the heart of the Feliks Audio Bliss is a fully tube-based, transformerless architecture operating in pure Class A. Despite the absence of output transformers, the amplifier achieves extremely high gain and delivers up to 1470 V peak-to-peak, ensuring effortless control over demanding electrostatic loads.

• Driver Stage Four carefully selected 6E5P NOS tubes, operated as triodes in a push-pull Class A configuration, provide exceptional voltage amplification, low plate impedance, and minimal harmonic distortion.
• Power Stage The symmetrical Hedge topology, built around 300B triodes, ensures ultra-linear operation, outstanding common-mode rejection, and an exceptionally wide frequency response by eliminating the Miller effect.

To maintain precise current control and stable thermal behavior, EL34 tubes are integrated into the circuit. The amplifier is supplied with matched 300B tubes and supports any standard 5-volt filament 300B, offering extensive flexibility for tube rolling.

Adjustable Bias for Maximum Compatibility

The Feliks Audio Bliss features an adjustable bias system, allowing perfect matching with both modern and vintage electrostatic headphones. Bias voltage can be precisely set via the front-panel control:

• PRO ONLY output (5-pin): 240–720 V
• NORMAL output (6-pin): 120–360 V

The NORMAL output always operates at half the voltage of the PRO output, ensuring safe and correct operation across all supported electrostatic standards.

Adjustable input sensitivity allows seamless integration with a wide range of DACs. For optimal performance, a high-output DAC delivering 5–10 V is recommended.

Precision Components and Flagship-Level Engineering

Every Feliks Audio Bliss is built using premium, carefully selected components. A 24-position DACT balanced stereo stepped attenuatorensures precise channel balance, low distortion, and long-term reliability.

The internal design features components from Vishay, Dale, Nichicon, and Jantzen, combined with Lundahl line transformers and custom Toroidy toroidal transformers for each channel. Advanced shielding and resin encapsulation provide excellent immunity against electromagnetic interference.

Critical signal paths are executed using point-to-point wiring, minimizing parasitic capacitance and preserving signal integrity throughout the amplifier.

Handcrafted Build and Timeless Design

Each Feliks Audio Bliss is hand-built by experienced specialists and subjected to extensive measurement and listening tests. Its substantial construction and refined aesthetics make it a natural centerpiece in any high-end listening environment.

The amplifier is available in three solid-wood finishes—Oak, American Walnut, and Zebrano. All wooden elements are machined, finished, and cured in-house to ensure durability and resistance to heat. No two units are ever exactly alike.

Technical Specification

• Driver tubes: 4 × 6E5P
• Power tubes: 4 × 300B, 4 × EL34
• Input sensitivity: 2 V / 4 V
• Maximum output voltage: 520 V RMS (1470 V peak-to-peak) @ 1 kHz
• Input impedance: 10 kΩ (RCA) / 10 kΩ (XLR)
• Gain: approx. 250×
• Adjustable bias voltage:
• PRO ONLY socket: 240–720 V
• NORMAL socket: 120–360 V
• Volume control: 24-position high-quality DACT stepped attenuator
• Signal inputs:
• 2 × single-ended stereo RCA
• 1 × balanced 3-pin stereo XLR
• Electrostatic headphone outputs:
• PRO ONLY 5-pin (580 V bias)
• NORMAL 6-pin (230 V bias)
• Automatic mains voltage adaptation: Yes
• Mains voltage: AC 120 V / AC 230 V, 50 Hz / 60 Hz
• Power consumption: 250 W
• Weight: 26 kg
• Dimensions (with tubes): 47 × 47 × 29.5 cm
• Dimensions (without tubes): 47 × 47 × 27 cm

Box Content

• Feliks Audio Bliss Electrostatic Headphone Amplifier
• 4 × 6E5P tubes
• 4 × 300B tubes
• 4 × EL34 tubes
• AC power cord
• User manual
• Warranty card