Abstract: A fluid amplifier comprising a housing having a cavity therein and a diaphragm in the housing dividing the cavity into first and second chambers. First and second supply passages lead to the first and second chambers, respectively, and terminate in first and second supply ports. The diaphragm is movable in the cavity to selectively substantially seal off the first and second supply ports. First and second control passages extend between the first and second supply passages and the first and second chambers. First and second signal passages are provided in the housing and terminate in the first and second chambers, respectively. The first and second control passages are in communication with the first and second signal passages through the first and second chambers regardless of which of the supply ports is sealed off by the diaphragm. First and second output passages terminate in the first and second supply passages, respectively.