Spherical speaker “Pluto”


Created on 15.04.2020 18:21.

Updated 04.15.

Author: Gelfenstein G.I ..

Speaker “Pluto” refers to electronic acoustics and is used in acoustic systems. This type of speaker is designed to improve efficiency and overall sound quality.

Structurally, the product consists of the following components. The speaker design is based on an electromechanical transducer (1), which in turn contains a magnetic system (2). An annular working gap (3) is located in the indicated magnetic system, and a voice coil (5) is installed on the frame (4), fixed by a centering washer (6).

Spherical speaker “Pluto”

A spherical shell (7) is connected to the electromechanical converter. The elastic spherical shell (7) is filled with a special sound absorber that increases the efficiency of the speaker. The sound absorber is fixed in the structure using a sphere holder (8) made in the form of a rod.

The rod, in turn, is attached with its upper end to the apex of the spherical shell (7). The fixation is carried out using acoustic dampers – special sound-absorbing washers (9) and (10). The lower end of the rod (8) is reinforced in the lower part of the spherical shell (7) by means of a frame (4). This design provides a pulsating vibration of the spherical shell containing the filler.

How the loudspeaker works

The audio signal of the set frequency passes through the voice coil (5). When a signal passes through the working gap (3), an alternating magnetic field is generated. This alternating magnetic field interacts with the magnetic system (2), which has a constant magnetic field. As a result of the physical process, axial oscillations begin in the coil (5). These vibrations through the frame (4) fall into a spherical shell (7) filled with a special damping material (11).

The upper part of the entire structure of the spherical shell is rigidly and motionlessly fixed by sound-absorbing damping washers (9) and (10). As a result, the vibrations of the spherical shell are carried out in the form of pulsations that form a pseudospherical acoustic wave.

In this case, a special sound absorber filling the shell (7) does not come into contact with it. Without loading the shell, the absorber dampens all vibrations that penetrate inside.

Structurally, to facilitate the placement inside the sound absorber (11) and create the shell (7) itself, it is created either as a collapsible one-piece. In the first case, the speaker is disassembled at the seams, and in the second, an upper hole is left in a solid shell, through which a damping material (for example, cotton wool) is placed. Subsequently, with the help of washer-dampers (9) and (10), the holes are closed.

Enhanced sound reproduction is achieved by creating a circular sound zone. And by reducing nonlinear distortion and expanding the uniformity zone of the frequency response, the efficiency of the entire speaker increases.

Patent SU 1 584 130 A1, August 7, 1990.

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