The artist who designed the cover is Paul Normansell, and the below info is from his official site:
The foundation of my work originates from the relationship between Art and Music. I wanted to try and create a link between colour, shape and sound. My abstract paintings are based on colour studies exploring how colours can stimulate feelings, emotions within a person, and the different meanings each colour has, and its power to evoke a certain response from the viewer.
From experimenting with colour my paintings became more illusional. I tried to create the illusion of movement, stimulating the eye into seeing things which may or may not be there. This seems to be testament to the human inclination to see patterns in randomness like looking for shapes in clouds or finding images within magic-eye pictures. The more you study the image the more you find. Each painting is individual, painted in gloss paint onto aluminium or board, each dot of paint is painted freehand using a brush. I use gloss paint and aluminium because of there reflective qualities and find it helps to enhance the optical effect of my work.