Ranga, which means “color” in Sanskrit, is perhaps best explained by the painter Cezanne: “Color is the place where the universe meets our minds.” The combination of Helfenrath’s musical ideas and de Jong’s Indian classical background gave rise to endless inspiration. Through their collaborations on several albums, as well as performances  in Amsterdam, they developed the concept of Inner Sound Design (I.S.D).

Helfenrath describes ISD this way: “The listener can create his own inner music; any sound can become music, depending on the way one listens. In the inner room of their minds the musician and the true listener meet. There is no difference between the one who plays and the one who listens. They are both listening. Because of this similarity, the listener can play without playing, and thus can also take part in the creation of the music. Any music will do for this purpose; it depends on the relativity of the listener. However, music which is open and has a deep trancelike quality seems to be more suitable.”