Good soundproofing elements near the property boundary - recommendations?

I would like to slow it down before it reaches our garden.

Forget it! If you shy away from (pleasant) confrontation, then do it once or twice with horrible Celine Dion music or Tabata crash sports music... starting at 9 am, when they are there themselves, but not yet in party mood. Maybe during Sunday breakfast?! That would hold up the mirror that most understand.

Forget it! If you shy away from (nice) confrontation, then do it once or twice with horrible Celine Dion crap or Tabata crash sports music... already at 9 o’clock, when they are there themselves but not yet in party mood. Maybe during Sunday breakfast?! That would be holding up a mirror that most understand.

Why kid gloves? Early at 7:00 circular saw.

Basically, such recklessness from the neighbors is already sad. I'm not sure, but have the neighbors lived there longer than you? Sure, you can rarely choose your neighbors, but it can't be that you have to isolate yourself from neighbors to such an extent by installing a two-meter high sound(!)proof wall, even if the neighbor is "in the right" with their music. A privacy screen to feel more undisturbed in the garden might still be acceptable... Therefore, it would certainly be the most sensible thing to start by seeking a conversation. She does seem willing to talk. Bass is indeed hard to "stop." When I was still renting, I agreed with my neighbor that she would please put a note on the door when she had a night shift. Then I knew I could turn my 5.1 system "a bit" louder :)

Basically, such thoughtlessness from the neighbors is really sad. ...

Maybe it is just carelessness? : what exactly does the noise barrier wall already passing by your property shield?

... In other words: a water feature (fountain, water jet, stream). ...

The idea is not bad in itself. However, there is a risk that one might have to run to the toilet constantly ...

Why kid gloves? Early at 7:00 a.m. circular saw.

But that is exactly not the reflection they are supposed to see and understand. In principle, it can only be the same, meaning the annoying guest visit over 3 consecutive days, then for others annoying music from a speaker, where their annoying tunes also came out. Otherwise, sooner or later there will be a fight.

Maybe it's just thoughtlessness?

Of course it is. Why would they do it intentionally? They're having fun, that's all – they don't worry that others are listening in and don't find it so great.