Details
Parallel Single-Ended 2A3 with Interstage Transformer Coupling
The Sun Audio SV-2A3TSX is a monoblock, parallel single-ended triode (SET) amplifier kit, designed for audiophiles seeking higher power output than s single 2A3, superior dynamics, and exceptional musicality. Featuring a pair of parallel 2A3 tubes per channel, interstage transformer coupling, and upgraded Tamura transformers, this amplifier delivers the legendary 2A3 tone with enhanced drive, resolution, and bass authority.
This is a kit, not a finished product. It includes all necessary components for assembly—including upgraded Tamura transformers, chassis, and premium-quality parts—but requires soldering and technical knowledge to complete.
High-Power 2A3 SET Performance
The SV-2A3TSX employs a parallel single-ended 2A3 configuration, doubling the output power per channel while preserving the natural warmth, midrange purity, and holographic imaging of the 2A3 triode. The addition of interstage transformer coupling between driver and output stages results in greater clarity, efficiency, and improved transient response, making this amplifier an outstanding choice for high-efficiency speakers.
Kit Features & Design
• This is a DIY kit – Assembly required; includes all necessary components.
• Monoblock Design – One chassis per channel for superior channel separation and power handling.
• Parallel Single-Ended 2A3 Circuit – Uses two 2A3 tubes per channel, increasing output power and drive capability.
• Interstage Transformer Coupling – Direct coupling between driver and output stages using a Tamura interstage transformer, eliminating capacitors in the signal path for improved clarity and efficiency. The first two stages are direct coupled, and the interstage transformer couples the circuit to the 2A3 stage.
• Upgraded Tamura Transformers – Premium Tamura power, output, and interstage transformers provide enhanced dynamics, tighter bass, and greater tonal refinement.
• Hand-Wired, Point-to-Point Construction – Traditional Japanese craftsmanship, designed for sonic purity and reliability.
• Tube Complement:
• Input/Driver: 6SN7
• Driver Stage: 6V6GT
• Interstage Transformer Coupling
• Output Stage: Parallel 2A3 (two per channel)
• Tube Rolling Capability – Compatible with various 2A3 tubes, allowing users to tailor the amplifier’s tonal character.
Specifications
• Circuit Type: Parallel Single-Ended Triode (SET), Class A
• All triode tube circuit with interstage transformer coupling
• Output Power: Higher than standard 2A3 SET (estimated 6-8W per channel)
• Frequency Response: 20Hz – 20kHz (+/-1dB)
• Input Sensitivity: 0.7V for full output
• Input Impedance: 100kΩ
• Output Impedance: 8Ω / 16Ω (selectable)
• Power Consumption: ~75W per monoblock
• Dimensions (per monoblock): W350 × H195 × D230mm
• Weight (per monoblock): 13kg
This is a Kit – Assembly Required
The Sun Audio SV-2A3TSX is only available as a DIY kit. It is intended for experienced builders who are comfortable with soldering, circuit assembly, and high-voltage electronics. No finished or pre-assembled version is available.
