Abstract: The disclosure of the present specification aims to provide a directivity control system for speakers, which is capable of easily controlling directivity of acoustic data to provide desired sound fields with a plurality of speakers, and freely producing sound fields with high accuracy. A plurality of physically connected speaker units are virtually arrayed at respective directivity angles according to control signals that define the directivity angles. Virtual delay time data is calculated for the case where data is outputted with the virtual array, and output is performed according to output data affected by the delay time data, so that desired sound fields can be formed with the speaker units remaining fixed, without the necessity of mechanically rotating the speaker units.

Abstract: The disclosure of the present specification aims to provide a directivity control system for speakers, which is capable of easily controlling directivity of acoustic data to provide desired sound fields with a plurality of speakers, and freely producing sound fields with high accuracy. A plurality of physically connected speaker units are virtually arrayed at respective directivity angles according to control signals that define the directivity angles. Virtual delay time data is calculated for the case where data is outputted with the virtual array, and output is performed according to output data affected by the delay time data, so that desired sound fields can be formed with the speaker units remaining fixed, without the necessity of mechanically rotating the speaker units.

Abstract: A conical helix decorative Christmas tree with lights attached is supported either on a pole or a bracket extending from a wall. If a pole is used, the base may be in a tree stand or a bracket attached to a wall. In both embodiments the base of the helix has a circle aligned by a plurality of strings attaching the circumference of the circle to a washer at the radial center of the helix. More than one helix may be used in this manner to form the tree. A shroud may be used to add a translucent decorative effect. A topper of a star, angel or continuation of the conical tree to a point may be added at the top of the conical helix tree. The tree can be attached to horizontal or vertical surfaces.