I don’t really have any experience with situations like this, but I’d be cautious of suggesting such things. Worst case they don’t do anything, and something happens to the neighbor and suddenly you have a lot of trouble waiting for you.

I know here in Germany you can create a log of all the occurrences of your neighbor being loud, end if it is excessive a court can order your neighbor to be silent. If your neighbor then breaks the order, the police will actually do something. Not sure how things work in the UK tho