KEF Teases New Products with World First Loudspeaker Technology
Let's face it, the basic principles of loudspeaker technology have not changed all that much in the best part of a century.
Speaker aesthetics have improved thanks to computer and 3D modelling techniques, and without doubt, manufacturing processes have improved dramatically.
What hasn't changed in all this time though, is that the enemy of music reproduction is distortion. Recent advances made through the use of new materials, mean that distortion levels are now dropping to almost unmeasurable amounts.
Famed British loudspeaker manufacturer, KEF, has today announced what it calls the “ground-breaking use of Metamaterial Absorption Technology”, or MAT. In joint research with Acoustic Metamaterials Group, KEF says the implementation of its MAT synthetic material will transform loudspeaker design.
KEF has created a synthetic material that has the super capacity to absorb all unwanted sound radiating from the rear of the driver, reducing distortion and enabling the prevention of audio distraction.
In a white paper released by the Audio Engineering Society in June 2020, a study was conducted testing KEF's use of Metamaterial Absorber for loudspeaker enclosures. The conclusion reads:
The implementation of an extremely innovative metamaterial absorber in a loudspeaker driver has been presented. The causal-optimal broadband absorber relies on a predesigned multi-resonator unit optimally packed in a very thin disk located at the back of the drive unit. A key aspect of the successful implementation is the optimal coupling between the loudspeaker diaphragm and the metastructure through a specific conical duct. The performance far exceeds the limits of conventional sound-absorbing structures such as reversed horns, achieving almost a near-perfect absorption spectrum starting at 620Hz with a physical thickness of 11mm only, whereas an exponential horn needs half a metre to reach equal performance.
MAT is a highly complex maze-like structure, where each of the intricate channels efficiently absorbs a range of specific frequencies, which when combined act as an acoustic black hole. KEF says this absorbs up to 99% of unwanted sound. Other traditional approaches are reported to have only allowed around 60% absorption. This difference between conventional techniques and MAT is said to be audible.
Dr Sebastien Degraeve, Research and Development Engineer at KEF, told StereoNET:
We want to absorb the sound behind the drivers because we want to hear the music and not any artefact created by the driver itself or the cabinet. We've created a metamaterial that is optimised to absorb the maximum of sound in a minimum of space.
It's understood that KEF will release a range of “contemporary speakers that benefit from MAT very soon”. The company adds that, “you only have to listen to believe.”