HDSP™.
High Definition Sound Projector.
Public address loudspeakers distinguish themselves through a more or less directional dispersion of a broadest possible frequency range. The purpose is to ensure that even in rooms with heavy reflections, a sufficiently high proportion of direct sound reaches the audience, thereby enhancing audibility. Conversely, this means that such loudspeakers must be aligned very precisely in the direction of the audience in order to avoid negative reflections. Thanks to the innovative HDSP principle, an almost rectangular room segment can be evenly supplied with sound energy.
There are two significant differences in comparison to common loudspeakers: firstly, the horizontal dispersion angle varies depending on the vertical angle, and secondly, the major part of the sound energy is radiated downward in a curved wavefront towards the audience, and not towards the walls or the ceiling. Several acoustic principles were combined in order to achieve this. The energy of the high-frequency driver is formed in a waveguide with varying path lengths to a vertically curved line, which is then radiated by the, in front of the waveguide positioned horn, with a width of 120° in the lower part and 60° in the upper part. In the transition to the low-mid frequency membrane, the sound signal is electronically delayed and phase corrected in such a way that the main inclined radiation axis is sustained over a wide frequency range. Likewise, the crossover frequency is selected in a way that the bundling resulting from the diameter of the membrane is equivalent to that of the mid-high frequency horn.
INSIDE HDSP™
A look inside an HDSP™ horn shows how the variation in horizontal dispersion is achieved. Clearly visible is the mouth of the waveguide which curves the wavefront more or less in relation to the horizontal dispersion.
The dispersion of the HDSP™ horn-waveguide exactly matches the dispersion of the speaker cone
Likewise, the crossover frequency is selected in a way that the bundling resulting from the diameter of the membrane is equivalent to that of the mid-high frequency horn.
As a result, the HDSP-range of KS AUDIO loudspeakers impress with an even and well-balanced sound pressure distribution both in the width and depth of space. Audibility is increased in a surprising way due to the small proportion of diffuse ambience. In most cases, there is no necessity to use different speakers in the short and long range, whereby a problematic transition range does not occur. This allows to reduce costs and the required installation volume in the installation area.
The vertical polar patterns show very clearly that the energy of the HDSP horn is directed in a 20° down-angle. This has to be seen in combination with the horizontal dispersion whereby the minimum dispersion of 60° occurs at the top of the horn and the maximum dispersion of 120° occurs at the bottom.
