Flat Screen Mounts, AV Furniture, Stands & Trolleys Sales & Consultancy
To visit our website, please click here
Over the last few years, there have been a number of technologies introduced that turn solid surfaces such as glass windows, wooden tables and desktops into loudspeakers, the actual sound is emitted from the actual solid surface, rather than an audio speaker.
One of the original companies that produced commercial flat panel speaker products was NTX Technologies. NXT produced its Distributed Mode Loudspeaker (DML) flat panel speakers, these were driven by magnetic coils mounted on the back of the solid surface. Rather then being a pistonic driver which physically moves the speaker diaphragm (membrane) forwards and backwards to produce sound waves, the moving coils or piezoelectric driver used by the NXT DLM technology causes the flat panel to vibrate to produce the sound from the whole surface. This technology has been used in products such as Clearsound, SurfaceSound & SoundVu, it has even been used in speaking or singing greetings cards.
This process of causing the solid surface to vibrate and emit sound by applying sound energy to it is common to all the technologies covered in this article, it’s the way the sound pressure is generated that differs between the technologies.
Feonic plc uses a powerful ‘smart’ material to produce sound energy that can then be applied to a multitude of applications. A smart material is one that reacts in a predictable way to an outside stimulus, in this case a small electrical charge. The smart material used is Terfenol, this is a grown crystal compound that expands rapidly when a small electrical charge is applied, this is called a magnetostrictive device. This Terfenol driven technology has been applied to both commercial and domestic applications such as the Soundbug and Whispering Windows. The Terfenol smart material is mounted on the back of the solid surface, actually touching the solid surface, when the electrical signal is applied the Terfenol expands and contracts incredibly quickly forcing sound energy into the solid surface, the solid surface then vibrates and emits the sound. Feonic Technology has been used commercially in the Soundbug, Whispering Windows, in marine applications and various others, including street furniture.
The newcomer to this arena is SFX Technologies, it’s Gel Audio products are being used and heavily advertised by MTV in it’s Wowee One portable speaker system. Unlike Feonic, rather than using a solid smart material, SFX Technologies uses a patented hydro-gel, when a small electrical current is applied to it, this produces a vibration energy which is then applied to the solid surface, in turn the solid surface is forced to vibrate to produce sound pressure waves. Currently, the SFX Technology is of course utilised in the MTV Wowee One product, however there are many commercial applications being developed.
All the above technologies employ an active sound driver mounted on the rear of a flat panel, this panel can be glass, wood, MDF, metal or almost any solid surface, they are not however suitable for use in low density fibre boards. As the production of sound depends entirely on particles to vibrate and pass the energy on to the next particle, the particles need to be reasonably well packed together, without air spaces between them.
The huge benefit for commercial applications is that unlike conventional speakers, there is no need to cut holes into the solid surface or to have ugly or intrusive speaker grills mounted on the visible side of the surface. As the solid surface does not need to be cut, then this opens huge market opportunities, particularly with outdoor applications such as street furniture and shop windows.
As the solid surface produces the sound, then this technology can be used for underwater applications, both for leisure and commercial applications. As all these technologies produce a diffused sound across a large surface area, then the overall volumes can be much lower than conventional loudspeaker, rather than being a potential source of noise pollution, these new technologies can be used to lower ambient noise.
For more information, please call 0845 835 0266