Thermal expansion matching for an acoustic telemetry system. An acoustic telemetry system includes at least one electromagnetically active element and a biasing device which reduces a compressive force in the element in response to increased temperature. A method of utilizing an acoustic telemetry system in an elevated temperature environment includes the steps of: applying a compressive force to at least one electromagnetically active element of the telemetry system; and reducing the compressive force as the temperature of the environment increases.