FiiO Class A

Fully discrete Class A transistor headphone amplifier with fully balanced architecture

• Fully discrete Class A transistor headphone amplifier
• Custom 60W toroidal transformer
• Fully balanced differential amplification architecture
• 20,000μF bulk capacitor reservoir
• 4000mW + 4000mW balanced output power
• 5 level gain control
• Toshiba twin and complementary audio transistors
• Sanken audio transistors
• DC servo output control
• 1/4 in. (6.35mm), 4.4mm and 4 pin XLR headphone outputs
• RCA and XLR preamplifier outputs
• 12V trigger input and output
• USB-C firmware update port
• ±10dB independent bass and treble adjustment

Fully discrete Class A transistor headphone amplifier

Rediscover the warmth of the analog era

As the core headphone amplifier of the retro style desktop HiFi system from FiiO, the CLASS A adopts a fully discrete Class A amplification circuit, meticulously built from individual audio transistors and carefully selected resistors and capacitors.

The components of each channel are precisely matched and manually tuned to recreate a pure, warm, natural and distinctly analog sound signature.

Two transistor types, one perfect union

The Toshiba twin and complementary transistors sound warm and smooth, with a relaxed low end and sweet, engaging vocals, lending the music a captivating emotional nuance.

The Sanken Electric audio transistors are precise and fast, with incisive dynamics and strong control, delivering effortless composure and authority in large scale orchestral and rock performances.

Clean power delivery, unleashing the potential of your sound

The custom 60W toroidal transformer is purpose built for the high quiescent current demands of a Class A headphone amplifier. It is painstakingly wound through multiple complex processes to provide efficient, low interference, precise and clean power, helping the amplifier fully realize its sonic potential.

The core is made of a continuous silicon steel strip. High magnetic flux density and low losses provide more efficient and cleaner energy conversion.

The winding is made entirely of copper enamelled wire. Low internal resistance and high current capacity deliver fast transient response.

Copper foil shielding for the primary and secondary windings reduces electromagnetic interference for a remarkably clean and quiet background.

A built in resettable thermal switch automatically activates protection in the event of overheating, ensuring stable and reliable long term operation.

The outer silicon steel shielding reduces leakage magnetic interference and helps prevent interference with the circuitry.

Well defined soundstage, effortless dynamics

A split power supply design provides independent regulated power to the multiple amplification stages, ensuring a clean and stable power supply with lightning fast transient response.

The 20,000μF high capacity Nichicon audio specific filter capacitors smooth the pulsating current after rectification while storing the energy needed for sudden dynamic peaks. They suppress mains frequency ripple to deliver clean DC and a deep, black background. When drums or full orchestral tutti hit, they release that stored energy quickly, so dynamics stay controlled and the bass remains tight and powerful.

Effortless high power output, fully balanced architecture

Featuring a fully balanced differential circuit architecture, the amplifier delivers strong interference rejection, low distortion, a spacious soundstage and ample driving power. With up to 4,000mW + 4,000mW of balanced output into a 32Ω load, it effortlessly drives a wide range of headphones, unlocking their full sonic potential.

Authentic Class A sound, carefully selected audio components

Built with carefully selected professional audio components, the CLASS A brings you the distinctive Class A experience: exceptional resolution paired with a warm, engaging musical character, balancing outstanding performance with effortless long term listening.

The amplifier uses 8 WIMA film capacitors, 20 ELNA audio capacitors and 20 high precision MELF resistors.

Restoring sonic truth with DC servo control

A built in high precision DC servo feedback circuit continuously monitors and automatically adjusts the output DC offset, correcting deviations and maintaining the output at zero DC offset. This not only protects your headphones, but also improves bass response and transparency, resulting in clearer sound, better control and more refined low frequency performance.

Pairs well with any headphones, tailor your ideal sound

Five gain levels: Low, Medium, High, Super High and Ultra High. The five selectable gain levels make it easy to find the right gain setting for different headphones, helping each pair unlock its full potential.

±10dB independent bass and treble adjustment: Whether you prefer a more immersive low frequency presentation or greater high frequency clarity, you can easily fine tune the sound to your preference.

Versatile connectivity, comprehensive inputs and outputs

4 inputs: 3.5mm single ended, RCA single ended, 4.4mm balanced and XLR balanced, easily pairing with any source device.

2 line outputs: RCA single ended and XLR balanced, to effortlessly connect power amps or active speakers and expand your system.

3 headphone outputs: 6.35mm, 4.4mm and 4 pin XLR, to drive mainstream headphones on the market.

12V TRIG IN/OUT bidirectional trigger: Link with upstream sources or control downstream amplifiers and speakers for convenient, one touch power on/off across your complete HiFi system.

Comprehensive protection for your equipment and headphones

Multiple built in protection circuits continuously monitor the device in real time and automatically respond when an abnormal condition is detected, helping protect both the amplifier and your headphones. Enjoy it worry free for years to come.

Protection features: headphone amplifier thermal protection, transformer thermal protection, output overload protection, output DC protection, power input overvoltage protection and overvoltage protection (OVP).

Retro desktop HiFi system, immerse yourself in rich analog sound

The desktop HiFi system from FiiO is purpose built for the desk. From source to DAC to headphone amplifier, every component shares a unified size and design language, keeping your setup clean and tidy. There is no need to worry about matching components, simply enjoy an immersive, pure analog listening experience.