I could be that noisy neighbour, bearing in mind DH and 3 x DS's play musical instruments. But, out of consideration they don't do it after about 8pm. 2am karaoke is very, very inconsiderate.
I do remember years ago when DH and I first lived together, our next door neighbour used to play drums at 3am during the week, as he said he was stressed. I asked him to stop at a reasonable time, even midnight would have been OK, we had to be up for work, he refused. I did warn him that we could be very much louder than he could even imagine, so he told me to eff off.
So, the next week we started having full band rehearsals in our front room, at about 4pm, when he was sleeping, including drums, bass, guitar, singers etc. After a week, I went round and said we would stop if he would stop. He stopped.