A fluidic device containing a flow through chamber comprising an inlet port, an outlet port, and a fluid permeable, compressible matrix located in the chamber between said inlet port and said outlet port, and said compressible matrix having a higher flow resistance at higher compressions and a plurality of flow paths leading from said inlet port to said outlet port through said matrix comprising shorter and longer length flow paths, wherein said matrix is compressed in at least one dimension, being more strongly compressed along the shorter length flow paths than along the longer length flow path.