Abstract: A diaphragm type cake compressor for filter presses employing recessed plates, which compressor comprises a planar panel of quadrilateral configuration and formed from a suitable inert material to define a lower central slurry feed through opening and at its corner portions at least one filtrate passing aperture and at least one separate wash passing aperture, which panel has applied to each face of same an elastomeric membrane, which membranes are secured in place by double sided adhesive tape applied about the margins of the panel and membranes, in circumambient relation thereto, with the membranes being coupled together and through the panel slurry feed through opening in sealing relation thereto to define the slurry feed through port of the compressor, and with the membrane being apertured to correspond to the panel filtrate and wash apertures, which apertures are sealed off from the slurry by adhesive tape bonding of the membranes to the panel.