Ceiling speaker a. Build in amplifier b. Hi-Fi quality sound effect c. Low distortion, low power consumption ... PHA-103F1 / PHA-103F2 Active Ceiling Speaker This speaker features Hi-Fi sound effect with frequency response ranging from 60Hz~20k Hz ... for familiers, stores etc..Build in amplifier with versatile connectorHi-Fi quality sound effectLow distortion, low power consumptionBalanced or Unbalanced ...