FELIKS AUDIO BLISS – THE UNSEEN AWAKENS

After over 4 years of development, Feliks Audio makes its first foray into the unique world of electrostatic headphones. The Bliss, then unnamed, was initially unveiled to the public during the High End Munich 2024 show as a prototype. Despite remaining concealed for the duration of the show, it has made lasting impressions, fueling the excitement of attending audiophiles. In 2025, at the same venue, the final version of Bliss was revealed to the world. Now, in its full glory, attendees got to experience the ultimate electrostatic performance, as well as the highest level of craftsmanship and finesse.

Despite being shown for the first time, the Bliss had already received high praise, garnering two Best of Show – High End Munich 2025 awards from reputable audio journalists – Soundnews and Headfonia.

“…when it comes to designing tube amplifiers that are both ferocious and beautiful, the Feliks brothers redefine the limits of possibility.”

Vitalis Sandu, Soundnews

Now, a few shows, countless smiles, and positive impressions of attendees later, this sentiment has never been truer. Widely regarded as the ultimate pairing for flagship electrostatic headphones, the Bliss consistently impresses.

An amplifier meant to push the boundaries

After the success of the Envy, the natural next step was to venture into the world of electrostatic headphones. The Bliss is an amplifier meant to push the boundaries of what is possible within that realm – its potential squeezing every ounce of performance out of your favourite e-stats. It is a device characterised by a natural, yet very dynamic and detailed sound signature, meant to entrance the listener in a hyper-realistic soundscape.

The Bliss’s versatility lies not only in its functionality. Its sound signature suits music of all genres, whether you’re a classical music enthusiast or a fan of EDM. Your music will get the treatment it rightfully deserves, reproduced faithfully and with authority, leaving no detail or nuance behind.

Carefully selected array of tubes

Feliks Audio Bliss uses a carefully selected array of tubes to deliver incredible gain, significantly enhanced frequency response, and greater interference immunity, free of distortions and power supply noise. At the driver stage, four 6E5P working as triodes are used in a push-pull pure Class A configuration. The power stage consists of four EL34 tubes and four 300B tubes. Matching the tubes of the Bliss properly is not just ordinary matching of quad sets – it involves obtaining the tubes’ full characteristics to create a perfect match. Swapping has never been easier – Feliks Audio keeps records of each unit’s tubes by serial number, to ease the future process of swapping, e.g., 1 of 4 tubes from a quartet.

Choosing the right tubes for the Bliss is not a matter of coincidence. The Bliss’s driver stage consists of four unique 6E5P (NOS) tubes working as triodes, offering incredible voltage amplification and sound performance. The 6E5P is an excellent driver for tough loads thanks to its low plate impedance. It is a tube perfectly suited for a push-pull configuration, capable of exceptionally high voltage gain. That, combined with a class A topology, provides low harmonic distortion, enhanced efficiency, and driving power for an unprecedented sound performance, not just to be measured by numbers.

A fully symmetrical Hedge topology

Past the driver stage, the phase-inverted signal reaches the 300B-based power stage. The power stage of the Bliss forms a fully symmetrical Hedge topology, characterised by ultra-linear operation, exceptionally low harmonic distortion, and very high CMMR (Common Mode Rejection Ratio). Most importantly, however, such a topology eliminates the Miller effect, maintaining an exceptionally wide and unrestrained frequency response while providing incredible gain.
Despite being a purely tube-based design with no output transformers, Bliss achieves exceptionally high gain and outputs up to 1470 V peak-peak. Unlike conventional designs, Bliss employs EL34 tubes as part of its precision current-control architecture. The EL34s are also used to dissipate heat from the amplifier.

Thanks to this solution, the Bliss maintains relatively low operating temperatures, allowing tight parameter tolerances and stable operation. The Bliss’s power stage uses the Stradi S300B tubes. These power triodes provide great frequency response and a precise, detailed, and airy sound signature. The S300B are carefully matched into pairs by the Korean manufacturer for ideal balance and operating conditions. The Bliss is compatible with any 300B tubes that have a standard filament voltage of 5 Volts, offering unparalleled freedom for future tube rolling and sonic exploration.

Meant to accommodate every electrostatic headphone

Feliks Audio Bliss is meant to accommodate every electrostatic headphone, no matter the voltage requirement, thanks to an innovative adjustable bias solution. Whether you own modern flagships that need 580 Volts or vintage classics that require 230 Volts, the Bliss can handle it all – just set the knob to your preferred voltage.
The construction sports two headphone sockets – a 6-pin NORMAL, and a 5-pin PRO ONLY socket, doubling down on the amplifier’s versatility. With the bias knob, voltage values for both sockets are adjusted at once, with the NORMAL socket outputting half the voltage of the PRO ONLY socket at all times. The voltage can be set between 120 Volts and 360 Volts for the NORMAL socket, and between 240 Volts and 720 Volts for the PRO ONLY socket. The Bliss can also be used with any DAC on the market, thanks to adjustable input voltage sensitivity, making it a perfect bridge between your favourite DAC and your favourite electrostatic headphones. It is recommended that the Bliss be used with a powerful DAC, with a voltage output ranging between 5 Volts and 10 Volts.

Carefully chosen to navigate the challenges of amplifier design

Years of rigorous testing of the Bliss resulted in a construction in which every smallest component is carefully chosen to navigate the challenges of amplifier design. To combat channel imbalance, high-quality, matched Lundahl transformers are used in tandem with a DACT balanced stereo stepped attenuator, which reduces inductance and stray capacitance, thereby improving reliability. The tried-and-true stepped attenuator is characterised by low distortion and improved accuracy, delivering the flagship performance befitting the Bliss. Even the smallest components used with the Bliss are of the highest quality, supplied by manufacturers like Vishay, Dale, Nichicon, and Jantzen, as well as Lundahl and Toroidy transformers. Internal wiring is custom-made in-house, specifically for the Bliss. Point-to-point soldering of critical components helps minimise parasitic capacitance, while thoroughly optimised signal routing and component layout ensure minimal interference levels and an exceptionally clean internal structure.
Following the inputs are Lundahl line transformers, allowing the phase-inverted signal to be precisely controlled at the driver stage.
Each channel sports dedicated custom toroidal transformers from Toroidy, using advanced shielding and resin encapsulation to ensure the amplifier remains immune to electromagnetic interference.

At Feliks Audio, we strive for nothing less than exceptional build quality. Each amplifier is hand- built by a team of experienced specialists, ensuring ultimate reliability and precision. Our mission is to redefine the market standard for premium headphone amplification, and the Bliss is a testament to that – hours of intricate work, meticulous measurements, and rigorous testing to provide our users with a unique product. Thanks to the majority of the production processes being done in-house, every unit is polished to perfection.

Feliks Audio Bliss is a monumental construction, becoming the centrepiece of any room it is displayed in. To perfectly match the design of your space, the Bliss is available in three beautiful finishes: Oak, American Walnut, and Zebrano. Every solid wooden part is machined and polished in-house. Then, the part goes through a multi-step curing process to ensure maximum durability and resistance to the heat emitted by the amplifier. The result is simple – Feliks Audio Bliss’s design speaks for itself, with no two amplifiers ever being the same.