Question: What do I do about my noisy neighbours below me?

So, I live above a tattoo shop (I know, I put myself into this issue) and they play music considerable loud in the evening. The close the shop at around 6, but the seem to gather in the evening and play really loud music.

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They re really nice and I don t want to cause any issues because I know they could easily make it louder.

How can I go about making it clear that they re being noisy without having to confront it head on?