Xin Zhi Zhao Schematic Updated -
Today, we are presenting the —a comprehensive revision that corrects previous errors, modernizes the power supply, and optimizes the driver stage for 21st-century preamp compatibility.
Whether you are a seasoned engineer or a bold beginner, use this V4.2 guide. Your ears (and your speakers) will thank you. Have you built the updated Xin Zhi Zhao? Share your build photos and measured voltages in the comments below. For more technical deep dives, subscribe to our newsletter for weekly amplifier schematic analyses.
The Xin Zhi Zhao is a amplifier typically utilizing the 300B vacuum tube. It earned its nickname, "The Little Chinese 300B," not because of its size, but because of its ability to produce "western" 300B sound quality at a fraction of the cost. xin zhi zhao schematic updated
| Metric | Old Schematic (2005) | Updated Schematic (2024) | | :--- | :--- | :--- | | | 7.2 Watts | 8.9 Watts | | Frequency Response (20Hz–20kHz) | -3.5dB (20Hz) | -0.8dB (20Hz) | | Signal-to-Noise Ratio | 82dB (A-wtd) | 94dB (A-wtd) | | Output Impedance | 3.2 Ohms | 1.9 Ohms |
| Component | Recommended Part | Budget Alternative | Why | | :--- | :--- | :--- | :--- | | | Western Electric (reissue) | Psvane WE300B | Low microphonics | | Driver Tube | NOS Sylvania 6SN7GTB | Electro-Harmonix 6SN7 | Matched triodes | | Coupling Cap | Jupiter Copper Foil | Solen Fast Cap | Smooths high-frequency hash | | OPT | Lundahl LL1663 | Edcor GXSE15-3.5k | Bandwidth for updated circuit | | Choke | Hammond 159S | Triad C-36X | Stiff power supply | Part 5: Step-by-Step Build Guide (Following the V4 Schematic) If you have the updated Xin Zhi Zhao schematic printed out, follow this sequence to avoid catastrophic failure. Today, we are presenting the —a comprehensive revision
Introduction: The Legend of the “Little Chinese 300B”
In the world of high-fidelity tube audio, few names evoke as much curiosity, controversy, and respect as the (often abbreviated as XZZ or Xin Zhao). For nearly two decades, this obscure yet powerful amplifier design has been a darling of the DIY community. However, until recently, the schematics available online were fragmented, often erroneous, or based on early prototype models. Have you built the updated Xin Zhi Zhao
This article is for informational purposes. Working with high-voltage tube amplifiers (400V+) can be lethal. Always discharge capacitors and use an isolation transformer.