Entertainment centres have been important features of homes since the introduction of the first consumer radios, and the considerations people put into designing spaces for music have increased in complexity as audio production technologies progressed. Architectural acoustics and engineering tend to be fields of expertise accessible only to industrial professionals, but more 21st-century homeowners are dabbling in acoustics to enhance their entertainment experiences.
In view of this rising trend, we assembled our team of experts to produce the following summary of points for homeowners to think about when designing their entertainment spaces.
The Nature of Sound
Sound is created by vibrations in materials such as our vocal cords, the diaphragm of speakers, and the reeds or strings of musical instruments. These vibrations travel through air in waves, spreading through spaces and bouncing off surfaces like water, while diffusing and reflecting as light does.
Sound is measured in terms of frequency, with low-frequency sounds being able to pass through thin materials and deflect around obstacles, while high-frequency sounds tend to be reflected by thin materials and do not overcome physical barriers as easily. This explains why low-frequency sounds such as the drone of traffic on a highway or the deep thumping of machinery on a construction site will travel much further than the relatively higher frequency sounds of human conversation which could be distinctly limited by a closed door.
Holistic Diagnostics
The average homeowner’s experience of improved sound comes from comparing the effects of a furnished room versus a hollow space. The low-frequency, bass-like quality of male voices is diminished by the solid frames of furniture rather than bouncing off the flat surfaces of an empty room – while the foam of upholstery, and fabric of drapery or carpets, also help to reduce high-frequency sounds. But furnishings can only do so much by inadvertently reducing sound for better or worse. Some areas such as corners or other spaces that are kept free for the sake of aesthetics or movement can act as unintended reflection points for sound.
Sound reflected from surfaces before reaching the listener produces an echo that distorts and reduces the quality of the listening experience. In order to locate reflection points in a room, our experts recommend using a mirror to find the points along walls and in corners where a listener can see the front of the speakers. Reflection points can be obscured by the placement of some solid furniture, or by the installation of purpose-built acoustic panels. Homeowners should also note that speakers come in a range of qualities, the more affordable models tend to scatter sound behind them as well as projecting sound in front, so consider searching behind speakers when looking for reflection points.
Professional Acoustics
The leading edge in acoustic engineering is demonstrated in anechoic chambers (silent rooms without echos). These rooms are entirely paneled in foam pads with long spikes or deep channels that trap sound waves and effectively cause them to disappear. These chambers tend to be used for industrial research – only the most well-funded recording studios can claim to be anechoic. A typical home entertainment centre would benefit from between 30% to 50% coverage with these types of panels.
Acoustic Foam Paneling
These foam pads tend to be available in a wide range of textures and colours, making them relatively easy to integrate with almost any style of décor. The mounting methods of acoustic foam panels include a range of adhesives, plastic clips, or bolts in metal frames.
Plastic clips attached to screws in the walls are the ideal mounting method proposed by our experts. Mounting methods consisting of numerous metallic parts tend to create noises of their own when vibrating in response to low-frequency sounds. Homeowners choosing adhesives to mount their acoustic foam panels should note that while curing time is typically measured in hours, the fumes of adhesives can linger for weeks or even months.
Theatrical Enhancement
Modern theatres are designed with acoustic reflector panels hanging on walls and from ceilings to distribute sound through a large space. This would not be a typical consideration for most homeowners but it is worth noting the difference between the smoothness of reflector panels intended to direct the travel of sound waves and the cellular nature of acoustic foam which traps sound.