Stereo Bluetooth 5.1 Mini Amp Board 50W+50W

Compact stereo amplifier module delivering 50W RMS per channel into 4–8Ω loads. Physical size: ~12.5 cm (L) × 8.5 cm (W) × 3.5 cm (H); net weight approx. 320 g. Designed for DC 18–19V input with minimum 3A current capability; operation above 21V is not advised when driving four speakers, and 24V+ supplies pose burnout risk depending on PSU quality. Enclosure uses impact-resistant plastic with exposed aluminium heatsink thermally coupled to power components and open-bottom chassis design to maximise natural convection cooling. Input options include Bluetooth 5.1 (up to 15 m range in line-of-sight), 3.5 mm AUX jack, USB mass storage (U disk), and USB audio interface mode. Outputs support both line-level (for active speakers) and speaker-level (for passive cabinets) connections. Volume is controlled via continuous-rotation encoder with dynamic LED bar graph (8 brightness levels). Power toggle: press-and-hold 1 sec; playback: click for play/pause, double-click to cycle among Bluetooth/USB/AUX. Also supports smartphone-based track navigation (shake-to-skip) and on-board U disk file listing. Embedded protection logic guards against short circuits, excessive current draw, temperature spikes, and static discharge — automatically entering safe state and signalling fault to internal controller upon detection.