TWO-WAY Audio Question

[salvananez]

Hi. I'm looking to setup a 32-ch NVR for the enterprise I work for.
I'm looking for a setup that makes possible to "talk" through the selected camera .
I want to purcharse 23 DS-2CD2135FWD-IS 3MP Dome Cameras. I 've read that the S stands for audio input and output. I know that I can connect a microphone to the camera to record video with audio.
But the in the specs for the NVR I'm looking for DS-7732NI-I4/16P. It advertises 1 RCA output for Two-Way Audio.

I'm confused about this. Can I have two way audio via the same ethernet cable? Otherwise. What's the camera audio output for?
Could someone guide me through this? :c

 

[Securame]

You would need to connect a microphone and speaker to each of the cameras to accomplish two way audio with that model.

You might want to look at the cube models, 2CD24xx, which have integrated mic/speaker (unless you need great microphones or huge speakers, in which case you do need audio input/outputs).

 

[fenderman]

You will need an amplifier to drive the speaker

 

[Fastb]

And research two way audio on an NVR.
It's not real time two way audio, as with a phone.
It's one way at a time. You click on the mic, and you can talk through the speaker which you'd have located near the cam.
While talking, you can't hear audio from the mic at the cam.
Un-click the mic icon, and you can hear again.
It's half-duplex audio. As with a walkie-talkie, with a Push To Talk (PTT) button.
Additionally, audio data travels over ip, so there's a real lag.
The Ring & Nest use VOIP (Voice Over IP), which prioritizes audio. (too bad their cameras are inferior, fish-eye, and often 720p vs 1080)
Office phones these days use CATx cable, with VOIP (as vs the only POTS analog audio). True VOIP workes well, and is full duplex. However, NVRs and ip cams don't use VOIP. Yet.

I want to purcharse 23 DS-2CD2135FWD-IS 3MP Dome Cameras.

Before pulling the trigger on that many cams, test with one first.
You may change your mind on form factor also. Research opinions here on domes, especially using domes outdoors.

Good Luck!

Fastb