A high definition distributed sound system has a master control hub with multiple serially linkable zones each capable of handling multiple serial arrays of powered speakers and a Cat5 cable. Each zone has an audio input, an internal master level controller and multiple powered-speaker outputs. Each of the serial arrays of powered speakers are connected to a corresponding powered-speaker output by the Cat5 cable. All of the zones can be used and controlled independently of the others or any number of them can be serially linked and controlled by their preceding zones. Additional master control hubs can be serially linked in a single system. The system interconnections can be done with Cat5 cable using RJ45 connectors. A low idle current power amplifier circuit offers extremely low levels of quiescent current, allowing a large number of speakers to be connected in one system.