This is what happens when I try to do something without thinking it through... I mounted the 1831C-PIR to a temp board at about the 6ft mark, setup an iPad about 5 feet behind it to record, then grabbed someone to stand in front of the camera to have a conversation with. They didn’t want to be on video, so I penciled them in. The audio for the entire video is low (I should have tested first), but if you adjust the volume up to where his voice is a normal level, you’ll hear how loud the speaker is. Heads up, when the video fades to black, the next section is how loud the alarm is, so turn it down a little for that. It’s not incredibly loud, but it’s loud enough.
I used the iDMSS app on my iPhone to talk back through the camera as well as trigger the alarm.