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noises typically become an issue when they translate into audible
sound. Vibrations diaphragmatically move walls and ceilings, converting
the vibrational energy into sound. This process is called transduction.
Just as the quality of the speaker and cables affect electrical signals,
so does the quality of the studs, drywall, fasteners, and paint on the
wall affect vibration.
Traditional acoustics is concerned with how the efficiency of transfer,
frequency response, and amplitude/volume of the sound is affected by
every single material in the chain of transduction. The impact of a material’s character on sound and vibration cannot be underestimated. The
obvious solution to controlling sound and vibration is to control the
materials in the room.
Consequently, materials science is an elemental part of acoustics,
even more so since the discovery of Quantum Acoustics®. Materials
science plays a significant role in both traditional and quantum modali-ties, one rooted in ex-post-facto solutions based on classical mechanical
behavior and the other in pre-facto, elemental solutions based on the
realm of quantum physics.
Using absorptive materials and diffusors, Traditional Acoustics controls
sound energy frequency by frequency and decibel by decibel (amplitude/
volume). Absorption is a way to diminish the amplitude or volume of
sound energy by trapping the sound energy in porous materials which
slow the sound down like a fast car trying to drive through a deep
puddle. The car slows down as it hits the puddle and the energy transfers into the puddle itself. Frequencies considered unpleasant or that
stand out unevenly are re-mediated using these traditional techniques.
Fiberglass batting such as Owens Corning 703 have been the most
popular choice for many years with newcomers like Thermafiber and
Roxul being widely used in recent history.
These absorptive materials are typically available in 2-inch to 4-inch
thicknesses and a variety of densities, affecting specific sound frequencies
based on both their density and thickness.
The most common misunderstanding is to use these absorptive materials
as global, broadband solutions. They are very specific in their control of
sound and not at all broadband controllers. Diffusors are typically wood
panels, which are designed to evenly spread sound energy across an interior
space. They look like panels made of complex slats or block arrangements
and are used in conjunction with absorptive elements for best effect.
Using these methods and more traditional acoustics seeks to control
sound energy by identifying and then controlling problematic frequencies
and amplitudes, remediating acoustical issues after the fact.
Using meta-materials and quantum physics applied to air molecules,
Quantum Acoustics® controls air at the molecular level. As air is the medium
on which sound travels, quantization removes the source of acoustical
issues before they can exist by quantizing any air molecule before it
contacts an interior surface. Air stops being a medium for the sound
energy by forcing air molecules to behave as individual particles and not
in groups as a wave. Hence, sound ceases to exist because it has no
medium to travel on.
Wherever applied, quantization is an acoustical cloak that removes
the ability of the material surface beneath it to affect sound whatsoever.
Quantum Acoustics® focuses on removing acoustical issues before they can
exist rather than remediation after the fact. It is a new technology based on
more than 100 years of applied quantum physics.
BELOW A close-up of a sample from DHDI's
collection of acoustical products. Materials
selection when designing a space helps
control sound and vibration.