Abstract: The present invention relates to sound reproduction apparatus comprising stereophonic amplifier means for amplifying left and right signals from any stereo emission source, and a plurality of loudspeakers disposed in two groups, namely one group on the left of a listening direction and another group on the right thereof, each group respectively receiving the amplified left signal and the amplified right signal. The number of said loudspeakers is even and not less than four, the loudspeakers being situated in pairs on axes that are vertical or substantially vertical, with all of the emission faces of said loudspeakers being placed on a surface of continuous curvature, and with the respective vertical and horizontal distances between said loudspeakers being determined as a function of the size of the loudspeakers and as a function of the listening volume.

Abstract: The invention relates to a process and a system for the display of time-variable quantities.The system comprises a computer, a memory for recording the values of the quantities, a clock, acquisition means for the values of the quantities, connected to the computer, as well as display means connected to the computer. The system also comprises means for simultaneously recording in the computer memory and at the same acquisition frequency, the development of the values of one of these quantities compared with the development of the values of the other of said quantities, or the development of the values of one of these quantities compared with the development of the values of the other of these quantities as a function of time, the computer controlling the display means in order to obtain the image of the graph or graphs representing said development or developments.Application to the display of the development of values of physical quantities.