TRIODO

The 2A3 & 300B TRIODO Single-Ended Triode (SET) Monoblock Amplifier

The TRIODO single-ended triode (SET) monoblock amplifier is engineered to uncompromising high-end standards, combining classic thermionic purity with sophisticated modern regulation.

Output Stage Versatility (2A3 / 300B)

  • Dual-Tube Compatibility: Allows the seamless use of either the 2A3 tube (approx. 3.5W, legendary for its holographic midrange) or the 300B tube (approx. 8W, offering enhanced headroom and bass authority).
  • Smart Auto-Bias: Automatically senses the installed tube type, dynamically adjusting both the cathode bias current and the filament voltage safely without any manual user intervention.
  • DC Filament Supply: Implements clean, tightly regulated DC voltage to power the directly heated cathodes, completely eliminating the 50/60Hz AC hum typical of DHT topologies.

Three-Stage Architecture

  • Input & Driver Stage (ECC82): The twin-triode ECC82 provides linear voltage gain and a low output impedance, effortlessly driving the demanding grid capacitance of the power tubes.
  • Low Distortion: Optimized inter-stage voltage swing guarantees that the signal reaching the 2A3 or 300B grid remains perfectly clean and symmetrical.

6H30-Based Shunt Regulated Power Supply

  • 6H30 “Super Tube” Control: Employs the ultra-high transconductance 6H30 triode as a lightning-fast parallel (shunt) regulator element.
  • Constant Current Draw: The power supply maintains a constant load, ensuring that audio signal fluctuations never modulate the high-voltage rail.
  • Inky-Black Background: Yields a near-zero power supply impedance, resulting in explosive macro-dynamics and an exceptionally low noise floor.

Custom Audiophile-Grade Lundahl Transformers

  • Premium Core Materials: Custom-specified Lundahl output transformers (OPT) utilize advanced geometry with silicon iron, amorphous, or mu-metal cores.
  • Extended Frequency Response: Delivers deep, uncompressed bass without core saturation, alongside airy, extended highs due to extremely low parasitic capacitance.
  • Neutral Transparency: Renowned Swedish engineering guarantees a flat frequency response and absolute timbral neutrality, leaving the audio signal completely uncoloured.

Switchable Feedback Topology

  • Zero Feedback Mode (0 dB): Delivers the purest harmonic texture, dominated by natural second-order harmonics. It offers maximum soundstage depth and requires high-efficiency speakers.
  • Low Feedback Mode: Applies a minimal amount of negative feedback to lower the output impedance, increasing the damping factor for tighter control over challenging bass drivers.

Boutique Selected Components & Scalability

  • Ultra-Premium Parts: Features non-inductive film resistors, audiophile copper-foil or paper-in-oil (PIO) capacitors, and heavy-duty chassis connectors.
  • Bridgeable Design: Offers a bridging option for audiophiles who demand higher power output while fully preserving the micro-dynamics and texture of the pure triode sound.

The opportunity to work with the 2A3

The Sonic Alchemy of the 2A3 Single-Ended Triode

While the 300B is often crowned the “King of Triodes,” true audiophiles know that the 2A3 is the connoisseur’s choice. When matched with high-efficiency loudspeakers, a well-implemented 2A3 Single-Ended Triode (SET) amplifier doesn’t just reproduce music—it breathes it into the room. It offers a sonic presentation that is purely addictive, defined by an almost supernatural sense of realism.

Midrange Holography and Presence

The defining characteristic of the 2A3 is its midrange. It possesses a luminous, lifelike texture that makes vocals feel startlingly physical. Singers do not just appear between the speakers; they stand in three-dimensional space, with every breath, lip movement, and vocal inflection laid bare. There is zero electronic glare or artificial etching. Instead, the music flows with a liquid, organic ease that solid-state amplifiers simply cannot replicate.

Micro-Dynamics and Instrumental Texture

Where larger tubes can sometimes paint with a broader brush, the 2A3 is a master of micro-dynamics and fine detail. It resolves the subtlest acoustic cues—the gentle brush of a snare, the wooden resonance of a cello body, or the trailing decay of a piano note into an absolute, inky-black background. String instruments possess a breathtaking combination of bite and warmth, capturing the actual tension of the bow against the string.

Soundstage and the “Disappearing” Act

The soundstage rendered by a 2A3 amplifier is vast, deep, and beautifully layered. It possesses a rare transparency that makes the boundaries of your listening room dissolve. Instruments are decoupled from the loudspeakers, suspended in a holographic field where the ambient space of the original recording venue is vividly recreated.

The Low-End Nuance

Do not let the modest 3.5-watt output fool you. While it won’t shake the foundations of your house with sub-bass slam, within its power envelope, the 2A3 offers exceptional bass articulation. It delivers a fast, tuneful, and highly textured low-end that perfectly captures the pitch and timber of acoustic double basses and kick drums.

The Listening Experience

 

Ultimately, listening to a 2A3 SET amplifier is an emotional experience. It strips away the mechanical barriers between the listener and the performance, delivering an intimate, pure, and tonally exquisite sound that speaks directly to the soul.