Abstract: An inlet silencer system for a refrigeration motor-compressor set. An inlet silencer is formed by a casing separated by a wall into two chambers which are coupled to each other by a coupling tube. A lid bearing an intake tube introduces refrigerant gas into the first chamber and a lead-in pipe connects the second chamber to the suction part of the cylinder head. The ratio by volume between the two chambers is in the order of 1. This ratio is determined to obtain a diminishing of the acoustic energy in the range of a frequency of 500 Hz. Furthermore, a chamber which is parallel connected on the suction path is used as a resonator to improve the attenuation and the acoustic spectrum. This device can be used on low-power, hermetically sealed, single-cylinder, alternating motor-compressor sets.