So you can communicate without waking up your sleeping infant, turns out. Though phones work for this too.

Stop worrying about waking up the kids with your noise, and they'll soon learn it's normal (even comforting) and sleep right through it.

That probably works great for your children, and I'm very happy for you, but not shouting works a treat for me. If a child slept through shouting that was loud enough in my house to be heard (we have 3 foot thick stone walls) I would be worried about their hearing.

Also, I mean this in the most polite way possible, but unsolicited parenting advice is often not received as well as one might hope.

If you're yelling enough for your children to no longer wake up from it, your neighbours will typically call a social worker.

I doubt they'd call the social workers over yelling "Mr. Watson come here - I want to see you."

Many DECT phones have this functionality without being wired. Also there probably is a way to use SIP locally as an intercom between smartphones.

Unlike an intercom they're portable.

The main thing missing is voice or sound activated pick-up and hang-up, sometimes automatic loudspeaker mode.

I rejected wireless intercoms at the time because every wireless thing I bought had horrible sound quality, like the worst walkie-talkie. Even with simple analog electronics, wired had good sound quality.

I did install some speaker wires, but the times when I wanted to play music in one room and hear it in another are just about never.

Guess I'm just not finding any point to home automation. Even if I had installed a home automation system, the intervening years would have turned it into expensive obsolete junk anyway. I've heard of people, when they try to sell their homes, having to rip it all out and put in conventional wiring.

What did pay off was running Cat5 and RG6 cables in a star configuration. Wifi has improved greatly, but it's nothing like a wired connection for smooth, problem free operation.

>I did install some speaker wires, but the times when I wanted to play music in one room and hear it in another are just about never.

I have speakers around my house, including on my deck, wired to a stereo receiver for music and I do use it. But Sonos didn't exist when I had the various renovations done when the wiring was added. If I were doing it today, I'd almost certainly just go with some sort of wireless system.