The module typically features a simple 9-pin interface for easy integration.
Some HW-104 boards integrate speaker terminals directly:
The HW-104 is a low-cost, dual-channel (stereo) audio power amplifier module intended for DIY audio, portable speakers, and low-voltage embedded systems. The board is not an IC but a breakout board typically housing a (or clone) IC. It operates from a single DC power supply and delivers moderate audio power with a simple "pop-free" start-up.
