Sound Description
The 6N2 + FU-19 high-end tube amplifier delivers exceptional performance: the FU-19 provides effortless control over the low frequencies, with tight, elastic bass and no muddiness. The highs are transparent and airy, full of life, while the midrange is sweet, rich, and aromatic like aged wine. The entire frequency range is exceptionally well-balanced, with precise vocal positioning that makes it feel as if the singer is standing right in front of you.
Product Features
- Compatible with CD players or computer audio sources (ensure your computer sound card has a line-out port; an independent sound card is recommended over an integrated one, as integrated cards may output about half the volume of a CD player).
- Fully AC filament supply ensures a noise-free experience, even with 90dB sensitivity speakers—so quiet, it feels like the unit is off.
- Utilizes a 6N2-driven FU-19 Class A amplifier circuit, delivering 8W+8W output power, ideal for speakers with 4-8 ohm impedance and 90dB or higher sensitivity.
- Features a Japanese ALPS 16-type volume potentiometer for precise channel balance and clear positioning.
- High-precision 1% metal film resistors and imported electrolytic capacitors are used throughout. Coupling is handled by Hong Kong TE MKP film capacitors, offering sound quality comparable to WIMA.
- CRC multi-stage filtering ensures a high signal-to-noise ratio. The filter network uses Swedish RIFA or Japanese Nichicon electrolytic capacitors paired with high-power metal oxide resistors. The tube filaments are wired in a 3.15-0-3.15 configuration with center tap grounding for superior AC hum suppression.
- All tubes are brand new J-grade: Beijing 6N2-J and Beijing FU-19.
- Custom-wound FU-19 (5K) 11W output transformer (model 664403) and 160W power transformer (model 965008), both handcrafted in-house for stable and reliable performance. The power transformer provides a full 160W, with a 96x50mm core that remains cool and vibration-free, complete with a top cover. The output transformer uses a 3+2 winding method and a 66x44mm core made from Japanese Z11 silicon steel sheets (0.35mm thick). Z11 offers higher magnetic permeability, resulting in deeper, more extended bass—significantly outperforming domestic H14 and H18 silicon steel. Transformers account for the majority of the unit's cost, hence the detailed explanation.
- Hand-wired point-to-point construction allows for easier future upgrades and modifications.
- Rated output power: 8W+8W per channel (thanks to tubes' strong overload capability, the actual undistorted output is comparable to a 40W+40W transistor amplifier). The unit supports both 4-ohm and 8-ohm output modes and is best paired with high-sensitivity bookshelf speakers, preferably 6.5-inch models within 80W power handling. Operating in Class A across all stages ensures minimal distortion, delivering sweet, smooth, and highly listenable sound.
Appearance & Dimensions
- Chassis Material: Solid teak wood (not veneer; solid wood costs significantly more than aluminum, iron, or stainless steel).
- Product Weight: Approximately 8.5kg
- Product Dimensions: Width: 300mm, Height: 145mm, Depth: 20mm (including tubes)
Specifications & Performance
- Input: One RCA input
- Output: Two sets of speaker terminals for 0-4 ohm and 8 ohm
- Frequency Response: 20Hz - 28kHz (±2dB)
- Signal-to-Noise Ratio: >95dB (A-weighted)
- Total Harmonic Distortion: <1% at 1W
Reference Diagram (Component values are based on actual parts; the diagram is for circuit structure reference only):
