Oh man this is rad. This is what done houses in the 70’s and 80’s had. A central sound system throughout the house.
I think you’re looking for a receiver obviously to handle the inputs but then you also need a multi-room amplifier. I’m pretty sure it also has another name, but something like this: Juke Audio
I’ll follow this thread because I’m always interested in everyone’s suggestions.
Probably not what you’re looking for but you can roll your own “smart” speakers that work directly with home assistant and play audio that way. Doesn’t help with audio input from like a TV, but it’s what I’ve got to offer at the moment because it’s what I’m working on at the moment.
Edit:the other name they go by is “matrix amplifier”. Good luck bud.
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