“...Nagel created his own universe, sometimes thwarted but never fully deterred: among other things, he animated three Musical Arabesques (1979-1982) using color pencils. He turned musical pieces such as Robert Schumann's “Dreaming” or Suite No. 4 by the GDR rock group Bayon into sensual and visual experiences through abstract plays of color and light. Nagel's art followed the tradition of German trick classics such as Oskar Fischinger and Walther Ruttmann. Nagel found a small, committed circle of fans, but was rather neglected when it came to theatrical distribution because his films did not correspond enough to conventional viewing habits.”   —Ralf Schenk, “The Colorful World of DEFA Animation"