Humor will not be tolerated!! -Portia

So we have some new neighbors who just moved in a few days ago. We haven't actually met them or seen them yet, but we're in a townhouse so we share a wall. They have something in their apartment that makes the world's most annoying thunking rhythm that transmits really loudly to a few rooms in our house. At first I thought they were hammering something into a wall, but after the perfectly constant rhythm went on for hours, I guess it's probably a ceiling fan that's loose and clunking on the ceiling a little? I don't know what else it could be.

But anyway, my question is this: what is the best way to tell them about the noise? I'm planning on going over there to say hi eventually, but it seems kind of rude to be like, "oh hey, welcome to the neighborhood, also GET OUR LANDLADY TO FIX THAT HORRIBLE FAN IT IS KEEPING ME UP AT NIGHT." Does anyone have any advice for letting them know how loud it is without being a jerk? Are there nice ways to tell a stranger that something they're doing in their own home is driving you nuts? I guess my other problem is that it seems unsocial to leave a note without ever having met them, and it also seems unsocial to bring it up the first time we're meeting them...thoughts?

Invite yourself in! (Well, if you're lucky, they'll invite you in, and if they do -- take the invitation!) Then while you're taking a little tour of the place figure out what's making the noise, and say, "Oh, that must be what's making the noise!"

They will probably take it from there.

/dispensation of advice

I finally met my next door neighbors yesterday after living here for 3 weeks. One of the first things I said was, "Do you hear our baby? our piano?" and they responded in the negative. They then asked if I heard their little girl throwing tantrums. I didn't. Anyway, I think we both feel a lot more comfortable around each other now that we know that all we hear of each other is walking around. So maybe you just need to see them and say "Do you hear our ____" with something like walking around or conversations. Then it might turn into a casual conversation about just how much you hear, and that's when you can bring up the thumping sound.

When you meet them I'd just ask them if they've heard a strange thumping noise. Don't let on that you think it's coming from their apartment.

If it were me, I'd want blunt. Wouldn't take offense.

Thanks everyone! I think I might bring them cookies or something in a nice, neighborly gesture but I'll make sure to say something about hearing a thumping noise from upstairs and saying that our landlady is really good about fixing things if it's something like a broken ceiling fan.