Grandstream GSC3518HS SIP/Multicast Talk-Back Horn Speaker (GSC3518HS)

The Grandstream GSC3518HS is a SIP/multicast talk-back horn speaker that provides crystal clear HD audio, a high-fidelity 50-Watt speaker, and IP66-rated water and dust protection. Ideal for outdoor campuses, public spaces, large offices, school playgrounds, hospitals, parks, warehouses and more, the GSC3518HS provides a powerful outdoor announcement solution that expands security and communication.

This high-powered SIP speaker includes 3 microphones, AI-based background noise reduction and intelligent text-to-speech (TTS) to ensure every word is heard clearly in talk-back scenarios. With a maximum SPL of 126dBA and a pickup distance of up to 8 metres, the GSC3518HS delivers expansive coverage in any environment. The GSC3518HS supports PoE++ input and PoE+ output, catering to device cascading scenarios, and includes differential LINE IN and LINE OUT connections for flexible audio integration.

The GSC3518HS supports Airplay, ONVIF, RTSP/HTTP streaming, local audio file playback and mobile app playback, alongside SIP paging, multicast paging, group paging and push-to-talk (PTT) with call-waiting priority override. Built with durable PC + ABS material, an aluminium back cover and a stainless steel mounting bracket, the GSC3518HS is designed to withstand harsh outdoor environments. It integrates with Grandstream's GDMS cloud platform and the broader Grandstream UC, facility management and IoT ecosystem.

Grandstream GSC3518HS Technical Specifications:

Speaker

• Speaker power: 50W high-fidelity
• Frequency response: 270 Hz–13.2 kHz
• Sensitivity: up to 109 dBA at 1m/1W (1 kHz)
• Max SPL: up to 126 dBA

Microphone

• Built-in microphones: 3
• Pickup distance: up to 8 m (26.25 ft)
• AI-based background noise reduction
• Intelligent text-to-speech (TTS) support

Audio Codecs & Telephony

• Voice codecs: G.711µ/a, G.722 (wide-band), G.726-32, iLBC, Opus, G.723, G.729A/B, in-band and out-of-band DTMF (In audio, RFC2833, SIP INFO), VAD, CNG, PLC, AJB, AGC, ANS
• Telephony features: SIP Paging, Multicast Paging, Group Paging, Push-to-Talk (PTT), call-waiting with priority override

Network Interfaces

• Network port 1: 1x 10/100 Mbps with integrated PoE/PoE+/PoE++ input
• Network port 2: 1x 10/100 Mbps with integrated PoE/PoE+ output

Auxiliary Ports

• 2x 2-pin Switch-in input ports
• 1x 2-pin Switch-out output port
• 1x differential line in port
• 1x differential line out port
• 1x DC 24V–48V input port
• 1x Reset

Power

• PoE++ input: IEEE 802.3bt, Class 8, max 71W, max input voltage 57V
• PoE+ output: IEEE 802.3at, Class 4, max 25W
• DC input: 24V/4A – 48V/2A

Network Protocols & Security

• Protocols: SIP RFC3261, TCP/IP/UDP, RTP/RTCP, RTCP-XR, HTTP/HTTPS, ARP, ICMP, DNS, DHCP, PPPoE, SSH, TFTP, NTP, STUN, LLDP-MED, SIMPLE, LDAP, TR-069, 802.1x, TLS, SRTP, IPv6, OpenVPN
• QoS: Layer 2 (802.1Q, 802.1p) and Layer 3 (ToS, DiffServ, MPLS)
• Security: user and administrator level passwords, 256-bit AES encrypted configuration file, TLS, SRTP, HTTPS, 802.1x media access control, secure boot

Management

• GDMS cloud management platform
• Firmware upgrade via TFTP, HTTP, HTTPS or local HTTP upload
• Mass provisioning via GDMS, TR-069 or AES encrypted XML configuration file
• Supports Airplay, ONVIF, RTSP/HTTP streaming, local audio files and mobile app playback

Physical

• Dimensions (L x W x H): 324.6 x 285.3 x 204.3 mm
• Unit weight: 2.870 kg (with mounting kits)
• Material: PC + ABS, aluminium back cover, stainless steel mounting bracket
• Installation: wall mount or pole mount
• Protection class: IP66
• Operating temperature: -30°C to +60°C
• Storage temperature: -40°C to +60°C
• Humidity: 10%–90% non-condensing
• Compliance: FCC, IC, CE, RCM

Package Contents

• 1 x Grandstream GSC3518HS Horn Speaker
• 1 x Mounting Kit
• 1 x Quick Installation Guide

Specifications Tab

Questions Tab