Traditional loudspeakers
Sound field generated by conventional speakers
The “piston” operation, typical of conventional loudspeakers, has a significant disadvantage. As the frequency increases towards and beyond the point where the wavelength in air is comparable to the size of the diaphragm, the acoustic output becomes increasingly directional.
You can avoid this by making the diaphragm small enough, but since the wavelength in air at 20kHz (the nominal high-frequency end of the audible spectrum) is only 15mm, it should be too small to allow generating useful output at lower frequencies.
To generate a given sound pressure level, the acceleration of the diaphragm must be constant, ie its excursion must quadruple with each halving of the frequency.
In practical use, shown in Pic.2, by virtue of what was described in the previous paragraph, the sound decay in relation to the listening distance is much faster than in a conventional loudspeaker (as shown in the diagram “Sound decay as a function of distance”.
It follows that the people present in the room will listen with a very different sound level depending on their position: those sitting in front will hear with a much higher level than the others.
Oyster AudioScreen Monitor
Sound field generated by the Oyster AudioScreen™
The AudioPanel exhibits different acoustic behavior from conventional loudspeakers due to the highly complex and nearly random nature of their vibration at frequencies sufficiently above the panel’s fundamental bending mode. More significantly, the AudioPanel does not tend to transmit its acoustic power as the frequency increases; instead, it maintains a virtually constant and wide directivity independent of frequency, whatever its size. Again, due to the complex nature of its vibration, the AudioPanel is also a diffuse sound radiator and this diffusivity reduces negative interactions with the boundaries of the room, which effectively act as acoustic mirrors.
In practical use, shown in Fig.1, by virtue of what was described in the previous paragraph, the sound decay in relation to the listening distance is very slow compared to a conventional loudspeaker (as shown in the diagram “Sound decay as a function of distance ”.
As a result, people in the room all hear at a similar sound level, regardless of their location.
AudioPanel
This is just one example of things you can do with AudioPanel. Contact us for more information on how to create your own product.