Mini 50W+50W Stereo Amp Bluetooth 5.1 Board

Dual-channel stereo amplifier board with 50W output per channel. Approximate dimensions: 12.5 × 8.5 × 3.5 cm; weight: ~320 g. Operates on regulated DC 18–19V input (≥3A required); for four-speaker configurations, maximum safe input is 21V — use of 24V or higher may result in irreversible damage depending on power supply stability. Housed in rigid plastic casing featuring externally mounted aluminium heatsink and open-bottom layout to enhance passive cooling efficiency. Audio inputs: Bluetooth 5.1 (15 m range in open air), 3.5 mm AUX, USB flash drive (U disk), and USB audio class support. Output flexibility: supports both active speaker inputs (RCA/line-level) and passive speaker connections (spring terminals). Volume adjustment via infinitely variable rotary encoder with progressive LED bar display (adjustable brightness: 8 levels). System control: hold 1 sec to power on/off; single tap plays/pauses; double tap switches between Bluetooth, USB and AUX sources. Also supports mobile device gestures (shake to skip) and displays U disk directory contents natively. Built-in hardware safeguards include short-circuit detection, overcurrent limiting, thermal throttling, and ESD hardening — all coordinated through internal fault-reporting protocol to preserve integrity under abnormal conditions.