How can I take benefit of instruments or devices that provide stereo output? A single S1 Pro+ multi-position PA System can Mix The 2 channels and fill the venue with one particular speaker. For devices or recorded material where stereo reproduction is essential, two S1 Professional+ Systems may be used https://www.bluetoothspeaker.top/outdoor-waterproof-bluetooth-speaker-high-powered-subwoofer-battery-powered-sound/