Wide power supply range: supports DC plus or minus 20V to 90V. With adequate power, it can reach around 200W, delivering good sound quality, strong drive, and capable when pushing a 15inch speaker without strain. Dualvoltage power supply guidance: the upgraded version optimizes the circuit and components. To directly apply voltage, it is recommended to stay under 90V and not exceed the voltage limit. Channel configuration: the board is a singlechannel power amplifier board and requires a dualchannel setup to form a complete stereo system. Circuit design and tube lineup: the design uses a dual differential circuit with the voltage audio pair tube A970 and C2240, and A1145 and C2705 for voltage amplification to drive the midpower pair tube A1837 and C4793. The output stage uses the power pair tubes A1943 and C5200. Use scenarios: DIY home audio: ideal for upgrading a system with large speakers, providing strong dynamics and clear sound, especially with a 15inch woofer. Small venue or rehearsal spaces: capable of delivering solid transient response and ample headroom when paired with appropriate speakers and power supply. Tube amp enthusiast projects: suitable for building dualchannel stereo configurations by pairing two boards, leveraging the listed tube lineup for amplification stages.