18KHz. Operating Temperature: -20 to 50 ° C. Dimensions: φ213 x 165mm. Network Wall Surface Mount Audio Speaker GEN-6011A03 Power Supply: DC24V/1A or POE. Interaction Procedure: TCP/IP, UDP, SIP, ONVIF. Signal-to-Noise Ratio: > 80dB. Frequency Response: 100Hz https://radio31851.answerblogs.com/30182761/reasons-why-an-ip-paging-system-is-important-for-modern-organizations