The album contains 10 tracks, most of them recorded in 2004. In a sense, one can say that Ruby four marks the passage from one millennium to another in Indra’s musical career. An interesting fact is that between 2001 and 2004 the artist did not have any musical productions.
Just like in the previous albums, here we meet a conglomeration of musical styles, which are obviously inspired by Indra’s conjunctions. Even so, it should be noted that the author turns slowly but surely to a pure electronic style, which we can also notice in the official albums he started to publish from 2005.