An air filter assembly comprising: a housing comprising a tube sheet separating the housing into a dirty air chamber and a clean air chamber; a plurality of venturi elements attached to the tube sheet, wherein each venturi element (30, 130, 230) of the plurality of venturi elements comprises a throat (32, 132, 232) located between a pulse inlet (36, 136, 236) and a pulse outlet (34, 134, 234), wherein a venturi axis extends through a geometric center of the throat and a distal end (137, 237) of the pulse outlet; a plurality of apertures in the tube sheet, wherein each venturi element of the plurality of venturi elements is positioned over or through an aperture in the tube sheet such that air passing from the dirty air chamber into the clean air chamber through each venturi element of the plurality of venturi elements passes through the aperture; and a plurality of filter elements (40, 240), wherein each filter element of the plurality of filter elements is positioned at the distal end of the pulse outlet of a venturi element to receive air passing out of the pulse outlet of each venturi element of the plurality of venturi elements; wherein a distal end (32, 132, 232) of the pulse inlet of each venturi element of the plurality of venturi elements is attached to the tube sheet such that the pulse outlet, the throat and the pulse inlet are located in the dirty air chamber; characterized in that: the pulse outlet of each venturi element of the plurality of venturi elements comprises a cross-sectional opening shape at the distal end that is non-circular, the non-circular cross-sectional opening shape including a generally oval shape, and the non-circular cross-sectional opening shape at the distal end of the pulse outlet of each venturi element of the plurality of venturi elements matches a generally oval opening shape of the filter element positioned at the distal end of the venturi element. a housing comprising a tube sheet separating the housing into a dirty air chamber and a clean air chamber; a plurality of venturi elements attached to the tube sheet, wherein each venturi element (30, 130, 230) of the plurality of venturi elements comprises a throat (32, 132, 232) located between a pulse inlet (36, 136, 236) and a pulse outlet (34, 134, 234), wherein a venturi axis extends through a geometric center of the throat and a distal end (137, 237) of the pulse outlet; a plurality of apertures in the tube sheet, wherein each venturi element of the plurality of venturi elements is positioned over or through an aperture in the tube sheet such that air passing from the dirty air chamber into the clean air chamber through each venturi element of the plurality of venturi elements passes through the aperture; and a plurality of filter elements (40, 240), wherein each filter element of the plurality of filter elements is positioned at the distal end of the pulse outlet of a venturi element to receive air passing out of the pulse outlet of each venturi element of the plurality of venturi elements; wherein a distal end (32, 132, 232) of the pulse inlet of each venturi element of the plurality of venturi elements is attached to the tube sheet such that the pulse outlet, the throat and the pulse inlet are located in the dirty air chamber; the pulse outlet of each venturi element of the plurality of venturi elements comprises a cross-sectional opening shape at the distal end that is non-circular, the non-circular cross-sectional opening shape including a generally oval shape, and the non-circular cross-sectional opening shape at the distal end of the pulse outlet of each venturi element of the plurality of venturi elements matches a generally oval opening shape of the filter element positioned at the distal end of the venturi element.