Abstract: The silencer device set forth herein in its various embodiments consists of at least one channelling bounded by at least one turn of a flat spiral, or of a cylindrical helix, or of a tapered helix, which may be blanked-off or open at one of its ends or at both of its ends, and/or incorporate radial holes or frontal holes in one or both faces. The outermost turn of the spiral, or the outermost surface of the helix, may either provide the shell of the device, or form a part thereof.