The QUBE speakers is collection of loudspeakers that provides to sound contractors and engineers tools they need to solve acoustical problems featured in QUBE powered speakers, HDD high dynamic device is an integrated system comprising digital processor and two high efficiency Class D PWM and Class G amplifiers. QRC 32 Network Interface some of Qube Active Series loudspeakers are equipped with built in network Interface with RJ 45 (In and Thru) connectors, capable of driving cable lengths of up to 100 meters (400 ft.) The QRC 32 USB interface features two channels, A and B, with each channel providing connection of up to 16 speakers for a total of 32 controllable speakers.