Fast dispatch and helpful advice before we placed a multi-site order. Pricing was clear and the product arrived ready for install.
Wesley G.
Grandstream GSC3518HS SIP Horn Speaker
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£238.00
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**Product Overview**
The **Grandstream** **GSC3518HS** SIP Horn Speaker is a high-power outdoor SIP/Multicast talk-back horn speaker designed for large-area public address, emergency alerts, and two-way voice communication in demanding environments such as campuses, industrial sites, parks, warehouses, and transportation hubs. It delivers extremely loud HD audio output (up to 50W / ~126 dBA) with integrated microphones for interactive communication.
Unlike standard paging speakers, the **GSC3518HS** is built for long-range sound projection and full SIP integration, allowing it to function as both a broadcast horn and a talk-back intercom device in IP-based communication systems.
**Ideal For**
- Outdoor campuses and school grounds
- Industrial sites and warehouses
- Public transport areas and stations
- Stadiums, parks, and large venues
- Hospitals and emergency notification systems
- Security and perimeter alert systems
**Benefits**
Its 50W high-fidelity horn speaker delivers very high sound pressure levels for long-distance audio projection, while built-in microphones with AI noise reduction allow two-way communication and voice response.
- The GSC3518HS is designed for maximum coverage and clarity in noisy outdoor environments, making it suitable where normal speakers would be insufficient.
- With SIP and multicast support, it integrates easily into VoIP and unified communication systems, enabling scheduled announcements, live paging, and emergency broadcast overrides.
- Grandstream GSC3518HS SIP Horn Speaker
- Heavy-duty stainless steel mounting bracket
- Installation hardware kit
- Documentation pack
- SIP & multicast talk-back horn speaker
- 50W high-power HD audio output
- SIP & multicast talk-back horn speaker
- 50W high-power HD audio output
- Up to ~126 dBA maximum volume for long-range coverage
- 3 built-in microphones with AI noise reduction
- Full-duplex talk-back communication support
- SIP paging, multicast paging, and priority override
- Text-to-speech (TTS) support for announcements
- Line-in and line-out audio interfaces
- Dual network ports (PoE input + PoE pass-through support)
- Supports ONVIF, RTSP/HTTP streaming, AirPlay, and local playback
- IP66-rated weatherproof and dustproof housing for outdoor deployment
- Product Type: SIP / Multicast horn speaker (talk-back capable)
- Model: GSC3518HS
- Audio Output Power: 50W
- Maximum Sound Level: ~126 dBA
- Microphones: 3 built-in with AI noise reduction
- Communication Type: SIP + multicast + full-duplex talk-back
- Audio Codecs: Opus, G.722 and other wideband codecs
- Network Interface: 10/100 Mbps Ethernet
- Power: PoE / PoE+ / PoE++ support
- Weather Rating: IP66 outdoor protection
- Audio Interfaces: Line-in / Line-out support
- Streaming Support: ONVIF, RTSP, HTTP
- Mounting: Heavy-duty outdoor wall/pole bracket
- Deployment Type: Outdoor / industrial / public area
**What's in the Box**
- Heavy-duty stainless steel mounting bracket
- Installation hardware kit
- Quick installation guide: Included documentation
- Documentation pack
**Shipping and Fulfilment**
- **UK delivery:** Standard, express and timed services are shown at checkout where available.
- **Dispatch:** Stocked products are prepared for dispatch during normal business days.
- **Large or project orders:** Delivery timing is confirmed with the order or quotation.
- **VAT:** Product prices are displayed excluding VAT; VAT is calculated at checkout.
Grandstream GSC3518HS SIP Horn Speaker
£238.00
Excl. VAT
· In stock for trade orders
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