Does anybody have experience of soundproofing the walls of a semidetached / terraced house which adjoin the neighbours, to prevent them hearing accordion / concertina playing and loud singing?    What did they use and did it work?   How did they deal with fireplaces ?   

I've read about acoustic plaster board glued directly onto the party wall, or building a false wall which doesn't directly touch the party wall, covered with acoustic plasterboard and soundbreaker bars, but all the information I've seen is from companies trying to sell their products.   I just wondered if anybody here might have tried any of these or other solutions and have any advice?   


Thanks

Joy
in the UK