In one embodiment, a device for measuring concentration of a paramagnetic gas is provided. The device comprises a measuring cell having a closed cavity therein, a reference gas conduit extending into the cavity for supplying a reference gas to the measuring cell, the reference gas comprising a predetermined concentration of the paramagnetic gas, a measurable gas conduit extending into the cavity for supplying a measurable gas to the measuring cell, the measurable gas comprising a measurable concentration of the paramagnetic gas, a first microphone differentially coupled to the measurable gas conduit and the reference gas conduit, and a second microphone located at a predetermined distance from the reference gas conduit.