An apparatus for forming a non-woven fiber web of fibrous material which includes a mixing chamber from which the blended fibers are fed into the fiber web forming chute where they are formed into a fiber web. The web forming chute includes a packing belt and a vibrating assembly each driven at selected speeds to compact the fibers into a fiber web of desired density. Volume dependent controls within the web forming chute act to control the rate of the feed rolls and the beater roll while weight or density dependent controls outside the web forming chute act to control the rate of the packing belt, the vibrating assembly and the size of the fiber web forming chute.