Important Notice: When testing the machine, always connect it to speakers. Testing under no-load conditions can easily damage the transformer or vacuum tubes (tubes may show a red glow). Damage caused by this type of operation is not covered by our warranty.
The wood grain on the chassis of the shipped unit will not match the grain in the product images, as each chassis has a unique pattern. Wood type: Sapele solid wood.
[Specifications]
Operating Mode: Stereo Push-Pull Class A
Output Power: >215W (RMS)
Frequency Response (-1dB): 20Hz–28kHz
Sensitivity: ≤1V
Distortion: ≤0.5% at 5W
Signal-to-Noise Ratio: ≥95dB
Power Consumption: <150W
Output Impedance: 4Ω, 8Ω
The preamplifier stage of this unit uses the Beijing 6N3-J (equivalent to imported model 5670). The driver stage employs the Beijing 6N1 (equivalent to imported models ECC85 or 6AQ8), known for its strong low-frequency performance. The power amplifier stage utilizes the EL84 pentode (directly replaceable with 6P14), a tube highly regarded in the audio community for its excellent performance. It features a large cathode area, long lifespan, and a high transconductance of ±1.3mA/V, ensuring high sensitivity and efficiency. The EL84 has been proven to deliver outstanding performance in practical listening tests. Pentodes offer the advantage of high amplification factors, providing greater gain in amplifier applications. Additionally, due to the dual shielding effect of the screen and suppressor grids, the interelectrode capacitance is minimal (e.g., less than 0.2pF for the 6P14), resulting in low high-frequency losses. While pentodes generally exhibit higher distortion and noise compared to triodes, this unit delivers a pure, natural, and transparent sound with virtually inaudible noise.
Attention, Buyers: All machines sold in our store are genuine pure tube amplifiers, utilizing output transformer coupling between the tubes and speakers. Experts understand that the unique "tube sound" is largely attributed to the output transformer. This is something that hybrid amplifiers or fake tube amplifiers (where tubes serve only as decoration) cannot replicate! All transformers in this unit are manufactured in-house, ensuring consistent parameters and no compromise on quality.
[Tube Amplifier Selection Tips]
Check the number of transformers installed: A genuine tube amplifier requires three transformers (one large power transformer and two smaller output transformers). The power transformer (Model: 1055013) in this unit provides a full 190W of power, with a 105x50 core. It operates without overheating or vibration and is crafted with copper wire and annealed silicon steel sheets. Mounted horizontally, it is a work of art even without a cover. The output transformer (Model: OP763501) is wound using a 3+2 method, with a core made of Japanese Z11 silicon steel sheets (0.35mm thick, dimensions 76x35mm). The Z11 core offers higher magnetic permeability, resulting in deeper bass performance, significantly superior to domestic H14 or H18 silicon steel sheets. Since transformers account for the majority of the machine's cost, we emphasize their quality. Additionally, the filter choke (Model: I573019) in this unit has an inductance of 5H and a current rating of 0.2A, contributing to a high signal-to-noise ratio. The background noise is barely audible even when placing your ear close to a speaker with 90dB sensitivity.
[Materials and Construction]
○ Fully hand-wired point-to-point construction.
○ Coupling capacitors: Sprague SPRAGUE 0.1µF. Filter capacitors: High-quality, low-impedance electrolytic capacitors from SAMYOUNG (Korea).
○ Resistors: Mostly imported carbon film and metal film resistors with copper leads. High-power resistors use metal oxide film types.
○ PCB wiring is neat and aesthetically pleasing, with minimal background noise.
○ Potentiometer: ALPS 16-type A100K.
○ Tube sockets: Ceramic with silver plating. Tube models: Soviet OTK (85% new) 6N14N x4, Beijing 6N3-J x1, Linlai 5U4G x1.
○ Power supply: Bridge rectifier with a 5U4G tube buffer, providing high current while protecting all other tubes.
○ Chassis: Sapele solid wood, dried, polished, and lacquered for a rich grain and elegant appearance. Top plate: 1.5mm stainless steel. Bottom plate: 1mm perforated and painted mesh. Metal plates help shield against stray interference.
○ Compact dimensions (35cm width, 25cm depth, 17cm height) and a sleek, low-profile design. Weight: 9.5kg, offering a solid and stable feel. Ideal for desktop or home audio systems.
○ Thanks to the custom-made output transformers with large inductance and a 76x35mm core, the unit achieves a low-frequency response down to 20Hz. It performs excellently not only for vocal music but also for large-scale symphonic works, rivaling amplifiers like the 1969 Class A, TDA7294, or LM3886.
○ Rated Output Power: 15W + 15W (Due to the overload tolerance of vacuum tubes, the actual undistorted output power is comparable to an 80W + 80W transistor amplifier!).
○ The unit supports 4Ω and 8Ω output impedances. It is best paired with high-sensitivity (88dB or higher) bookshelf speakers, preferably 8 inches or smaller, with a power handling capacity of up to 100W. Full-range paper cone speakers add a unique charm to vocal music. As all tube stages operate in Class A, distortion is minimal, delivering a sweet, smooth, and highly enjoyable sound.
○ For safe shipping, we use extra-thick packaging, and tubes are packaged separately. You will need to install the tubes upon receipt.
[Schematic Diagram] As shown in the image.
