welcome to the core forum
without going into amplifier design…and types generally …
it uses the same ground point for each channel in this and most cases…its just duplicated …
so you would connect your leads to this board by joining both grounds to its ground pad…or just use a 3.5 mm phono stereo to rca lead and use the onboard audio jack
in the case of bridged amplifiers…etc and alike.they have two separate grounds or earths if you will…
depending of the amplifier class design
