Apologies for the length.
I live in a flat and have new neighbours who live directly below me. They’re young, I’d guess mid-late twenties at best, and also from another country. I can’t quite place the accent but that’s irrelevant, what’s relevant is that there is likely a language barrier.
Since they moved in less than a week ago they’ve been blaring music throughout the day. So loud that it vibrates my floors and can be heard from every inch of my flat. It’s not constant but it’s a lot. I’m usually home from work around 5pm and it can be on and off until 10/11pm. There has been one or two days where there hasn’t been any music at all.
I want to approach them about it as my last neighbour was the same and it made my life hell until she finally moved out a few months ago. I live alone and look younger than I am so feel quite vulnerable. I also don’t live in a great area, there’s a lot of break in’s both in homes and shops, junkies, drug dealers etc which makes me feel even more vulnerable and a bit of an easy target. I will be selling my flat for obvious reasons but probably not for another year or two due to costs.
I don’t want to be a dick about it but I also don’t want to let them take the piss. I’ve been miserable in my own home since I bought it due to my last neighbour and would like to have some sort of peace for the next couple of years. I don’t expect silence but I do expect a bit of common decency and respect from others in the building.
They don’t seem like very friendly, approachable people and I have a strong feeling they may be drug dealers (spotting them is a talent I have obtained since living here

). The constant smell of weed, people coming and going all day and night, flashy car and head to toe designer clothes were the first signs. There was also an instance at the weekend, so a couple of days after they moved in, where someone targeted the flat and attempted to smash the windows in.
Would it be ridiculous if I put a note through their door asking them to keep the music down? I don’t want a face to face interaction due to feeling vulnerable and don’t want them to know it’s me and be the face of the complaint. I’m also a bit worried that it might come across more rude than I intend to be due to the language barrier so thinking it might be better written down.
I’m aware I’m overthinking it but my last 4 years here have been hell on earth due to a multitude of reasons. The council and police have never been interested in helping me and I’m fed up of feeling defeated and depressed in the place I’m supposed to call home.