Slab Sound Analysis

The images you see here show the activity on the surface of a Slab panel as it moves and flexes to create the frequencies we hear as music or speech.

Panel example:
Dimensions: 200 x 300 Panel: 3mm thick Edge: Simply supported

Abstract:
This document contains mesh and contour plots generated by computer modelling. These plots show the magnitude of displacement of the panel surface. The model has been prepared for the 200 x 300mm Slab loudspeaker. It is intended that this document provide a computer simulation of the surface activity of a Slab panel. These images were originally created in the old fashioned way by sprinkling sugar onto the panel and observing the surface activity at various frequencies.

Comments:
These results have been prepared using the simple isotropic panel model. In the computer model it is assumed, in the computer model, that the panel is simply supported. The actual Slab loudspeaker may have some amount of momentary resistance at the boundaries. The effect of this will be to reduce the displacement of the surface around the perimeter and increase the natural frequencies. The model has been prepared with a structural damping factor of 0.01. This is an arbitrary value. Testing and measurement continues. The following columns of images show on the left the pattern that is activated on the panel to create the frequencies we hear as voice and music. The column on the right shows an exaggerated 3d image of the surface of the panel. The images here show the activity when looking down on a panel (left picture).The picture on the right is a 3-d image. The activity is recorded at 3,500Hz.

The lower examples from left are; 100Hz, 600Hz, 2,000Hz, 4,000Hz, and 5,000Hz.

The images you see here show the activity on the surface of a Slab panel as it moves and flexes to create the frequencies we hear as music or speech.