Grandstream Conference Phones, SIP Speakers and Intercom Stations in Oman

The GAC2500 is the practical choice for a standard meeting room seating six to ten people. Three cardioid microphones cover 360 degrees out to about 3.6 meters, and it runs a 7-way conference bridge on the device itself, so you can pull in several remote callers without a PBX conference room.

It runs Android 4.4, which is old. Treat it as a very good speakerphone with a touch screen, not as a platform for current meeting apps. A daisy-chain port lets you link a second unit for a long boardroom table.

The GAC2570 is for boardrooms and rooms that change shape. Twelve microphones pick up voices at 5 meters, and you can add two optional GMD1208 wireless desk microphones up to 20 meters away for a long table.

It has a built-in 3,300 mAh battery rated for up to 4 hours of talk time, so a call keeps going if you have to move rooms halfway through. Grandstream lists it as Zoom certified, and HDMI in lets you bring a laptop into the meeting.

The GSC3516 is a speaker that can also listen. Page a warehouse floor, a school corridor or a clinic waiting area, and someone standing under it can answer without walking to a phone. Four microphones cover a 4.2 meter pickup distance.

It handles SIP paging, multicast paging and push-to-talk. A 2-pin input takes a call button, which turns it into a simple help point at a gate or a service counter.

The GSC3570 is the box on the wall at reception or in a security office. It takes intercom and paging calls on a 7-inch touch screen, and its relay output can switch an electric lock or a light, so a guard can answer a call and open the door from one place.

It has no camera of its own. It can display H.264 video streams up to 720p from other devices on the network. Four alarm inputs take door sensors or buttons.