The Bogen Nyquist Gen-2 Series NQ-S1810CT-G2 ceiling speaker provides superior HD audio quality and seamless integration into the Nyquist ecosystem. There is no need for external amplifiers, traditional intercom wiring, or transformer taps to manually set or adjust. Connect the speakers via Cat5 to a PoE Switch or PoE Injector, and they are ready to operate. Volume is controlled via the Nyquist GUI Dashboard. These Gen-2 VoIP speakers also offer a Form-C relay output for controlling/overriding third-party devices like AV sources. As one would expect from Bogen, the HD audio quality is superb, with excellent incoming and outgoing intelligibility. Many two-way speakers use the speaker itself as the microphone, resulting in poor talkback audio quality. The Nyquist Series VoIP speakers use a separate high-performance MEMS microphone to achieve superior talkback audio.