Sound insulation

The wall between me and the neighbours who are having building work done in parallel with me is only one brick thick. Their daughter's music used to drive me nuts so in the alcoves on the ground (and first) floors I am having sound insulation between their living space (and bedroom) and mine. There will be no sound insulation between our respective utility rooms and bathrooms. I hope that doesn't prove to be an omission.

I once lived in a house whose previous occupants were musicians who had turned the basement into a sound-insulated recording studio with sand between the floors. This will be nowhere near that quality.