Directional sound amplification products suitable for outdoor playground areas in schools and similar environments aim to concentrate sound energy on the crowd in the playground while significantly reducing noise emissions to unrelated areas. The core technologies include wideband constant beam and wide-beam forming, adaptive beam forming, sidelobe suppression of sound arrays, array unit selection algorithms based on deep learning, and speaker detection technology and systems. These products can achieve uniform coverage in typical playgrounds and offer high speech clarity, minimal ground reflection, and low field boundary sound emissions.