For over twenty years, Arjen Lucassen's musical inspiration is a dance between psychedelia and progressive rock mixed with a genial approach in the forge of his mind. However, 2004 was a special year for Ayreon, because "The Human Equation" was affecting its profile with a more pronounced metal trend and a tendency to more "moderne" progressive structures. A decisive contribution in this direction come decisively with the selection of singers . An high-quality choice where the popularity of the names is absolutely secondary to the artistic caliber of voices appearing in this excellent concpt album. Plus the way they were intertwined with music is simply astonishing: James La Brie, Mikael Akerfeldt, Devin Townsend and the late Mike Baker. A must have.