Synaesthesia (also known as Synæsthesia) was initially an anonymous project for Bill Leeb and Rhys Fulber of Front Line Assembly and Delerium to further explore their ambient ideas. The sound of Synaesthesia is basically the continuation of Delerium's boding ambient basis of their early albums such as "Stone Tower" before their gradual shift of genre towards trip-hop - the same ambient music that was released under the Delerium moniker around the time of "Semantic Spaces".