GB1310165A - Sound radiator - Google Patents

Abstract

1310165 Loudspeakers ELEKTROAKUSZTIKAI GYAR 17 March 1970 [26 Nov 1969] 12793/70 Headings H4J and H4X A loudspeaker system comprises a zig-zag array of at least three baffles (Fig. 7) on each of which is mounted one or more loudspeakers. The baffles are flat and the radiation axis of the or each loudspeaker is perpendicular to the flat front face. The baffles are at a common level and each two adjacent baffles meet at an angle angle substantially different from 180 degree along a meeting line. All the melting lines are parallel. A first flat panel is common and perpendicular to all the baffles and is positioned above or below them. The baffles meet the panel in a zig-zag line. The projections on to the panel of the radiation axes of sound from the baffles are alternately in front of and behind the zig-zag line. Adjacent baffles have centres of radiation which are spaced from each other by a distance smaller than ten times the wavelength of the upper limiting frequency of sound emitted from the baffle having the higher upper limiting frequency. The upper limiting frequency is the frequency at which the response measured along the radiation axis has decreased 10dB below the mean response over a bandwidth of one octave in the region of maximum sensitivity. Preferably two panels perpendicular to the baffles are provided one at the top and the other at the bottom as shown in Fig. 7. Arrangements of four baffles (Fig. 8, not shown) and five baffles (Fig. 9, not shown) are described. The baffles may mount a plurality of loudspeakers, and the loudspeakers may be identical or different (Figs. 14, 15). Vertical wooden rods 18 (Fig. 20b) may be placed in front of the loudspeakers 5 to alter the directivity patterns. Two zig-zag arrays may be mounted one above the other, there being a lower and upper panel perpendicular to the baffles and a common perpendicular panel between the zig-zag arrays (Fig. 10). Alternatively the common panel is omitted (Fig. 11, not shown). The upper array may be out of step with the lower array (Figs. 12, 13, not shown).