Abstract: A technique for correcting the voice spectral deformations introduced by a communication network. Prior to the operation of equalization of the voice signal of a speaker, the constitution of classes of speakers is communicated, with one voice reference per class. Then, for a given speaker, the classification of this speaker is communicated, that is to say his allocation to a class from predefined classification criteria in order to make a voice reference which is closest to his own correspond to him. Then, for that given speaker, communicating the equalization of the digitized signal of the voice of the speaker carried out with, as a reference spectrum, the voice reference of the class to which the speaker has been allocated. This technique applies to the correction of the timbre of the voice in switched telephone networks, in ISDN networks and in mobile networks.

Abstract: Piston-cylinder unit including a working cylinder; a piston attached to a piston rod and installed with freedom of axial displacement in the working cylinder; and fastening elements, at least one of which is screwed into a threaded bore in the piston rod, where the interior pressure in the working cylinder holds a valve in the bore of the piston rod against an end surface of the fastening element. A vent groove leading to the atmosphere is provided between the end surface and the valve to create a pressure gradient to the working space, the groove being provided between the inner surface of the piston rod and the fastening element.