planar dimension of the finished panel perpendicular to that represented by the length of the laminated strips fig3 illustrates another method of forming the core 11 flat rectangular sheets 21 of corrugated fiberboard having at least one planar dimension equal to a nominal planar dimension of the finished panel 10 are stacked to a height equal to the other nominal planar dimension of the panel the sheets are permanently attached to one another with glue or adhesive at their interfaces the result is a block 22 which in the illustration of fig3 is a cube the block 22 is sliced with a saw along a plane denoted by lines x x and y y spaced nominally 1 inch from a side of the block to form a core successive cores 11 are formed by more cuts each spaced a distance of 1 inch from the preceding cut the flutes 19 of the core 11 extend perpendicularly to its major planar faces the face sheet 12 is an acoustically transparent medium or film optionally painted with proper air flow resistance that can serve as the appearance side visible to an observer in a room in which the panel 10 is installed the face sheet 12 is adhered to the core 11.