The basic definition of decoupling is to separate objects. Decoupling to isolate sound is most commonly done with resilient sound clips, resilient channel, or specialty framing like double stud or staggered stud walls. Sound vibrations will transfer best from material to material rather than through open space. An example of this would be sound transfer from drywall to framing and then to the drywall on the other side. Stop this transfer with decoupling by reducing the number of connections (resilient sound clips) or by breaking the path entirely (specialty framing).