Xin Zhi Zhao Schematic Updated May 2026

| Component | Original | Updated | |-----------|----------|---------| | First cap after rectifier | 100µF (causing high inrush) | 47µF + NTC thermistor | | Choke | None (resistor only) | 5H–10H, 200mA | | Second cap | 220µF | 330µF | | Shunt regulator | None | TL783 or LR8 (for B+ ~400V) |

Whether you are repairing a vintage build, constructing a new amplifier, or simply modernizing a tired project, adopting these changes will bring your tube amplifier into the 2020s while preserving its soul.

Ready to start? Download the verified schematic package from the official DIY audio repositories, gather your components, and prepare to hear your Xin Zhi Zhao amplifier as it was always meant to sound: silent when it should be, and glorious when it sings. Xin Zhi Zhao schematic updated, XZZ tube amplifier, 300B schematic update, DIY tube amp power supply, CLCRC filter, shunt regulator for tube drivers, heater elevation, ground loop elimination. xin zhi zhao schematic updated

→ 5U4GB rectifier → 47µF/500V → 10H choke → 330µF/500V → 10kΩ/5W → 100µF/450V (supply for driver)

The directly addresses these three weak points without sacrificing the signature tonal character. Part 2: Key Changes in the Updated Schematic After analyzing three verified revisions (credited to a collaborative effort on diyAudio.com and a Chinese-language forum Hifidiy.net ), here are the five most significant updates. 2.1 Power Supply: From CRC to CLCRC + Shunt Regulator The most dramatic change is in the power supply. The original single-stage CRC filter has been replaced with a CLCRC (capacitor-inductor-capacitor-resistor-capacitor) network followed by an optional shunt regulator for the driver stage. Xin Zhi Zhao schematic updated, XZZ tube amplifier,

| Parameter | Original | Updated | Improvement | |-----------|----------|---------|--------------| | THD+N at 1W | 0.85% | 0.41% | ~50% reduction | | Noise floor (A-wtd) | 1.2mV | 0.28mV | 23dB quieter | | Hum (120Hz component) | -62dB | -78dB | 16dB better | | Bandwidth (-1dB) | 25Hz–35kHz | 12Hz–42kHz | Extended bass/treble | | Damping factor | 3.2 | 4.8 | Better speaker control |

In the niche world of high-fidelity vacuum tube amplification, few names command as much quiet respect among DIY enthusiasts as Xin Zhi Zhao (often abbreviated XZZ). Known for blending vintage warmth with modern engineering rigor, Zhao’s designs—particularly his push-pull and single-ended triode (SET) schematics—have become blueprints for thousands of home-built amplifiers. ground loop suppression

But as with all classic circuits, time reveals opportunities for improvement. Power supply filtering, ground loop suppression, and thermal management are areas where the original 2000s-era schematics have begun to show their age. Enter the —a set of modern revisions that has been circulating through DIY audio forums, GitHub repositories, and PCB design communities over the last 18 months.