The music sounds like it is segmented into little grains, rather than flowing in one continuous piece. Not liquid or fluid. Suffering from harmonic or I.M. distortion. Some early A/D converters sounded grainy, as do current ones of inferior design. Powdery is finer than Grainy.
composed of or covered with relatively large particles; "granular sugar"; "gritty sand"
(1) A descriptive term for gritty texture which is desirable in certain hard-grating cheeses, though not to the point of mealiness. Parmesan and Romano exhibit a granular or grainy texture. (2) A flavor term that may be used to describe the grainlike (wheat) flavors that occur as the result of ripening.