Denon Professional’s range of ceiling loudspeakers is designed to deliver exceptionally accurate, articulate sound while easily meeting commercial requirements for fire-resistance (EN 54-24) and suitability for multiple unit installation. It features a metal “can” rear enclosure, which provides a fire barrier behind the speaker to meet commercial fire codes. It also serves as the woofer’s enclosure to optimize its bass tuning and low frequency response. The speakers have 70/100 volt transformers to facilitate multiple unit installations without the impedance and level-matching concerns of paralleled transformer-less speakers.