The differences between invisible and conventional sound technologies are marked and should be celebrated, writes Keziah Newlove, marketing manager at Amina Technologies…
Invisible speaker technology has no doubt come of age and while its development and application will continue to evolve, companies embarking on the provision of invisible audio solutions for clients need to think outside the conventional speaker box. There are many ways to create sound, however when it comes to invisible solutions, the ‘conventional’ rules don’t apply.
It is not enough to adapt a conventional speaker and force it to do something it was never designed to do. Consumers want more. They want a product that creates a blanket of sound, with clarity rather than a compromise. To find their way in achieving this, manufacturers have adopted various technologies. Some have created variants on OEM arrangements or attempted to copy other’s fundamental designs, with varying degrees of success.
However, generally, the technology adopted is either a full DML structure, or a part DML structure in the upper ranges, supported by conventional bass drivers that set up an air pump under a panel surface to get it to move more to generate lower frequencies. While DML is the much newer audio technology, it actually derives from a much older place – a musical instrument. Before sound reproduction existed, musical instruments were the sole way to listen to music. The natural musical instrument concept forms the basis of DML, which along with thousands of hours of R&D, testing and feedback, is creating literal waves across the invisible speaker market. It’s a different sound, an immersive blanket, and its benefits and purposes are as valuable as those creating standalone conventional technology.
You may also be interested in:
Everyone is different, and this difference is important in creating new and interesting movements within the audio industry.
Over the past 20 years the creation and evolution of the invisible speaker market has created a drive for constant improvement and strive for excellence among suppliers.
With any new technology, adjustments in specification have to be made. That’s true with DML technology, but like lots of emerging technologies, DML offers a number of advantages over the traditional. One of the key things to keep in mind is that you cannot be restricted by the rules that conventional speaker design dictates. DML invisible speakers allow for a much broader placement selection, as symmetry is not required. It is imperative to remember the purpose of the product.
Invisible speakers are not used as critical listening devices, but rather to create a listening environment that allows the listener to move freely while still maintaining amplitude and full frequency response anywhere in the room. Spread source (DML) devices reach further, interact much less negatively in acoustically challenging spaces compared to conventional ceiling or wall speakers, and generally require less overall power. They also radiate 360 x 180°, a half-sphere, covering a much larger space allowing fewer devices to be specified.
AV specifiers, unfamiliar with the physics of this type of product technology and its immersive reproduction capabilities, tend to over-specify the product. Some simply replace the same number of conventional speakers they might have specified in the past, with DML devices. In practice, and depending on room geometry, the reality is that far fewer DML devices, perhaps four times fewer, can be specified, while still retaining a smoother overall SPL level within the space.
Although such DML devices can individually be more expensive than a conventional speaker, the overall system costs, with not just a reduced number of speakers, but reduced wiring and reduced amplification requirements, can actually be far lower.
With ‘invisible’ being critical to the overall visual look and finish of the space, installers do need to take responsibility for working with and supervising onsite tradespeople. They are the ones both preparing the infrastructure correctly and finishing the decoration. Both are important to get right. If a metal frame ceiling structure is badly constructed many audio devices may set up spurious ceiling noises, not just integrated DML devices. The quality of the overall room aesthetic at handover to the client will very much be determined by the quality of the plastering effort ensuring levels are all correct across the installation surface.
One of the challenges for invisible technology is that the uninitiated often have a perception that “invisible speakers cannot create sound properly”, and sound is muffled because they have no grill. How does sound travel through plaster? The actual opposite is true of DML speakers. As sound is only created by exciting air molecules, the conventional loudspeaker converts electrical energy into sound by moving the surface area of the ‘loudspeaker cone’ back and forth, creating a point-source. DML speakers use the same electrical energy via transducers to create resonant pockets of sound, just like the soundboard of a natural musical instrument, to create a truly immersive sound quality while ensuring a clutter-free and flexible environment.
Why is it that a violin can cover a room corner to corner, very evenly and without room reflections destroying the original timbre of the instrument, and multiple guitars or pianos can sum together without interfering with each other? That is because these instruments are based on the principles of sympathetic resonance, creating amplitude through the sum of tens to thousands of tiny pockets of sympathetic vibrations from a soundboard. The sound source is spread out over a larger space, a ‘spread source’, and enters the room as multiple individual sound sources, spreading out in all directions to fill the room making it non-directional.
Creating a forum where people can understand that invisible technology is different, and should be celebrated as such, is key to overcoming misunderstanding. The acoustic performance (frequency response, tonality, clarity, etc) of the best products on the market today can indeed match those of very good conventional loudspeakers. What a lot of people don’t understand though is the dramatic advantages DML technology can provide over conventional speakers. It creates a new sound, an immersive output that enhances the whole house audio experience beyond conventional cone speakers.
This is a ‘speaker-less’ solution that can be installed behind not just plaster, but in a way that gives aesthetic and design freedom with a myriad of finishes, while always filling a space with very even sound.
The product itself isn’t blended into the wall, it becomes the wall. It changes with décor, never falling out of style. It becomes mirrors, a marble media wall, a beautiful piece of furniture, a conference room ceiling tile or indeed an elegant room by day and a highly capable cinema by night. A product capable of being used for the lifetime of a building and not just a few years, giving it great environmental credentials.