I've known a couple of Shih tzus and they were both quiet dogs. I think the Pug sounds like a good dog for an apartment.
My Chihuahuas are very quiet unless someone is at the door, drives up the driveway, seen on a walk, when the UPS man is here, when I stomp my snow off my boots outside the door, when a coffee up is set down too hard in another room, when another dog barks on TV. LOL. When they're just hanging out and nothing happens, they're quiet as a mouse. And they're good about stopping when I tell them "enough." Well, Chulita is really good. Jose` is not perfect.
My Doberman doesn't bark unnecessarily. But my son's dog barks the most of all of our dogs. She is worse than my Chi's and she's a GSD-Pit mix, we think. She has yet to be taught better that she doesn't have to react to every little thing. She has the most abrupt and loud bark. She will stop when you ask her to, but my goodness and then she starts again. It's quite annoying.
Along with the breed I also think it has to do with what noises a dog is use to
Definitely. I can attest to that. When I first visited my daughter's apartment in Seattle, the dogs barked at all kinds of noises....neighbors closing their doors, people talking and walking on the street below, traffic, car alarms.... These things do NOT happen where we live. But as I visited a few more times and even though I only go there about 4 times a year, they are onto the idea that it is normal there for these noises but it would not be normal here. And they're all relatively quiet when we visit, thank goodness.