the process disclosed enables the &# 34 ; time domain aliasing cancellation &# 34 ; method to be extended systematically to larger block overlapping . the boundary conditions which , when using various modified transforms , the analysis and synthesis windows must comply with , can thus be given . the transform series must also be included in the design of each analysis and synthesis window in order to optimize for a given application , because this changes the boundry conditions with which an analysis window function can be determined . design for analysis and synthesis windows have shown that analysis and synthesis properties obtained by multiple block overlapping are significantly better than those obtained by convential double block overlapping . the systematic method of the invention offers numerous possibilites for optimizing windows in special applications .