Most modern installations for architectural audio, digital signage, restaurants, corporate boardroom audio system, classroom audio systems, retail merchandizing kiosks and background music systems, etc. need a compact and robust speaker. The PHA-4 is a very good fit for such applications. It offers audiophile quality of high-performance, high-efficiency and very well defined dispersion pattern. This small yet powerful package delivers true high-fidelity performance that actually rivals the sound quality of large speakers. This miniature yet powerful package delivers high performance and quality at an affordable price.