The A2+ features analog amplifiers that are built into the left speaker, while the right speaker is passive so setup is simple. Just plug the left speaker into AC power and connect the included speaker wire from left to right. We’ve included minijack, RCA, and USB inputs for easy connection to your computer or phone and tablet and other cables you may need are included. There is no software or plug-ins to install and A2+ works with any computer or music player. The A2+ also has a variable RCA output for connecting a subwoofer, upgraded connectors, improved accessory cables, and a redesigned power supply.