Master Class
Can be used as a preamplifier or headphone amplifier
True Class-A
Fully discrete
Twin-JFET input stage
Two current modes & four gain stages
99-step R2R volume control
Three pairs of output transistors connected in parallel per channel
New high/low-voltage power supply architecture
Separate power supplies for digital and analogue sections
100-watt linear toroidal transformer
Solid aluminium remote control
0.6A Class-A current per channel
12W output power
Dual toroidal analog transformer
Two gain levels
MUSES R2R volume control
40000uF capacitor array
Twin JFET Input Stage Circuit
The A17 adopts a Twin JFET (Junction Field-Effect Transistor) input stage design. JFETs inherently possess voltage-controlled characteristics similar to vacuum tubes, delivering a natural, smooth, and richly layered sonic character. By employing dual-transistor parallel architecture, linearity is further optimized, allowing the signal to acquire a full and solid texture from the initial amplification stage. Instrument imaging has solid physical presence and fine luster, while vocal reproduction is delicate, refined, and emotionally engaging. This design not only enhances musicality but also provides a more stable and purer signal foundation for the subsequent power amplification stage-making it a defining element of the A17's signature sound.
Isolated Dual Power Supplies for Analog and Digital Control
The analog section is powered by a 100W toroidal transformer, while digital control uses a separate supply. Digital isolators prevent interference. A large 80,000µF capacitor bank ensures stable power delivery.
New High / Low Voltage Split Power Supply Architecture
In fully-discrete Class-A amplifier design, increasing the supply voltage is key to achieving greater dynamic range and higher linearity, but it also brings significant heat generation-an inherent consequence of lower energy conversion efficiency. The A17 innovatively adopts a split power supply architecture with separate high-voltage and low-voltage rails. The pre-amplification stage operates at ±20V, ensuring ample dynamic headroom and a spacious soundstage, while the output stage runs at ±15V, effectively managing heat generation while maintaining driving capability. This partitioned power supply approach strikes an ideal balance between sound quality and efficiency, allowing the A17 to maintain stable operating temperatures and consistently high sonic performance even during extended Class-A operation.
