Understanding the Difference Between High-, Middle- and Low-Frequency Noise
The best architects understand that sound is an integral part of the experience of a space. But it’s not just a matter of whether a space is “loud” or “quiet.” There are many different types of sound, often categorized as high frequency noise, middle frequency noise, and low frequency noise.
Not only do sounds in each category reverberate differently in architectural spaces, but the balance between high pitched sound, middle, and lower frequency sounds dramatically affects how one experiences a room. For maximum control of your aural landscape, keep reading to understand the differences in frequencies and how to optimize each one in architectural design.
The Fundamentals of Sound Frequencies
Sound is, at the most basic level, vibrations passing through a medium—usually air. The wave caused by these vibrations can bounce off of reflective surfaces or be absorbed, resulting in different architectural spaces providing noticeably different sonic experiences.
These sound waves come in different frequencies, meaning the vibration occurs faster or slower depending on the sound’s source. The unit used to measure frequency is the hertz (Hz), representing one cycle per second. A lower Hz value denotes a lower amount of vibrations per second, and, therefore a low frequency sound wave.
The Spectrum of Sound Frequencies: Low, Middle, and High
The human ear can detect a wide range of audio frequencies, from about 20 Hz at the low end to 20,000 Hz at peak frequency. However, most human speech, music, and desirable ambient noise fall into a much narrower band in the middle of the frequency spectrum, ranging from about 100 Hz to 3,000 Hz.1
Impact of Different Frequencies on Architectural Acoustics
The acoustic design of an architectural space should simultaneously balance desired frequencies and absorb (or block) undesired frequencies.
How Low Frequency Sounds Behave in Architectural Spaces
Low frequency sounds, technically falling anywhere below 300 Hz, are the source behind that rumbling you feel in your chest at a concert from a bass-heavy song. The closer these sounds are to 20 Hz or lower, the more you feel them in your body.
High Frequency Sounds and Their Interaction with Architectural Elements
A high frequency sound begin around 2,000 Hz. The older people get, the harder the very highest range of frequencies (10,000 Hz+) becomes to hear. Room elements like carpets, acoustic curtains, and acoustic panels can be used to absorb higher frequency sound s in a space.
The Middle Ground: Mid Frequency Sounds in Architecture
Between 300 Hz and 2,000 Hz lies the middle ground of sound frequency. This is where most day-to-day sound falls. In the standard commercial setting, this is the range of frequencies that sound treatment aims to maximize and optimize. This is because optimizing mid sound level frequencies makes for clearer speech, music, and other human-intended audio.
Practical Applications in Architectural Acoustic Design
Architecture is both a science and an art, requiring attention to both style and function. Depending on an architectural space’s use cases, the type of acoustic design can vary wildly. A standard meeting room needs mid-frequencies to be audible, while a library or quiet workspace would require all frequencies to be managed.
Those who do acoustic consultation and offer professional soundproofing services will have a wide range of techniques and soundproofing materials in their arsenals to make sure any space’s acoustical needs are met.
The Art of Soundproofing: Techniques and Materials
Soundproofing is the most comprehensive method for controlling a space’s acoustics. The goal of this technique is to prevent any sound from entering or escaping. The best assets for soundproofing are heavy doors and thick walls without any gaps for the sound wave to escape through.
Acoustical Surfaces provides options like Mass-Loaded Vinyl that can be installed to bolster thinner or more porous walls.
Understanding Noise Transfer and Its Effects on Sound Quality
Knowing that sound is vibrations traveling through a medium is essential for managing sound quality in an architectural setting. For example, machinery can conduct low-frequency vibrations directly through concrete or other building materials to offices and workplaces nearby. In cases like these, sound absorption and soundproofing materials like acoustic foam and wood wool can make the difference between a productive workday and a headache.
The Future of Acoustical Design in Architecture
In a world increasingly focused on the effects of the environment on human well-being, optimizing the acoustic profile of a space has never been more important. Studies have shown that loud sound or environmental noises are detrimental to health and happiness.2
As the world continues to urbanize, more people than ever are being concentrated in denser settlements, where they’re more exposed to environmental sounds or background noise. This trend makes both commercial and residential soundproofing more necessary than ever.
So before you kick off your next architectural project, be sure that you have the right sound tools and partners in place. An acoustic consultation of your space can light the way for the most optimized sound for the experience you intend to provide residents and visitors.
Make Waves with Acoustical Surfaces
Acoustical Surfaces provides a bevy of options for both sound treatment and soundproofing. Whether you want to cultivate a precise balance of frequencies or block out sound entirely for a silent sanctuary, ASI has the materials and the know-how to do it. For commercial spaces, rest assured knowing our LEED Certification backs our work.
Sources:
- Ask Audio. The Highs and Lows of EQ. https://ask.audio/articles/mixing-essentials-the-highs-lows-of-eq
- National Geographic. Noise Pollution. https://education.nationalgeographic.org/resource/noise-pollution/
