Contact your local noise abatement officer. They will send you diary logs so you might as well start keeping a diary now.
You will be lucky if they move quickly though. It has taken more than 2 years and threats to sue the Council for them to finally tell our neighbour that they will take enforcement action if she does not stop. Last time I complained, they put up a lock box so that she would stop waking us up at night to let her in. Only problem is, they did it while she was in hospital and didn't tell her it was there or how to use it. After she came out, her preferred method of entry was to ramrod the security door until we let her in and then complain that we hadn't been quick enough.
The Housing Officer came out and showed her and then said to me afterwards 'of course it doesn't have a key in right now' - but in her view they have now dealt with that problem.
We have now been sent yet another pile of logs. The problem is that the other neighbours in the block are too old (late 80s and 90) to deal with these on their own, don't speak English well and are not good at dealing with administration, so I spent hours last time helping them with them. I haven't got the strength to do it again.
She is getting aggressive and is physically very tough so it is very intimidating. I have seen her attack people but the Council is convinced that she is a victim and is defending herself because she got the flat because of domestic abuse.
She has had a fight with her drug dealer and so she is not filling the building with the smell of skank for now but she will find another one. Then we have unsavoury characters coming into our small block.
Your neighbours are not going to change as they don't think they are in the wrong and whether any further action will be effective will depend on how good your council is. After they get the logs, they will serve a Noise Abatement Notice demanding the noise stops and if they don't a fine will be payable.
This may stop the noise but it will cause an atmosphere and you have to decide if it is worth it. It might also make them decide that they want to move so it is all guesswork really.
I think that problems have to be confronted but there can be blowback.
I know someone who received a Notice. She denied that they had done what they were accused on but did take it seriously.
I would drop then a line, people respond very differently to complaints put in writing, and also contact the Noise Abatement Officer. If they stop after getting your letter, then you won't have to proceed with the complaint and they won't know that you have made it. If you wait you will have to put up with it for longer while filling in the logs.