The quietest room in the world, also known as the anechoic chamber at Orfield Laboratories in Minnesota, is a place where sound is almost completely absorbed rather than reflected. With a background noise level of -9.4 decibels, it holds the Guinness World Record for being the quietest place on Earth. But who actually owns this unique room and facility?
Quick Answers
– The quietest room in the world is located at Orfield Laboratories in Minneapolis, Minnesota.
– Orfield Laboratories is an independent testing facility owned and operated by Steven Orfield.
– The anechoic chamber at Orfield Labs holds the record for the world’s quietest room as recognized by the Guinness Book of World Records.
– The background noise level inside the anechoic chamber measures -9.4 decibels.
– For comparison, typical sound levels range from 0 decibels (the threshold of human hearing) to 120+ decibels (a jet engine at takeoff).
All About Orfield Laboratories
Orfield Laboratories was founded in 1968 by Steven Orfield as an independent testing facility. The lab conducts acoustic testing and research across a variety of industries including aerospace, automotive, consumer electronics, defense, medical devices, and more.
The company’s unique anechoic chamber was originally built in the early 1990s to provide customers with one of the most accurate and quiet testing environments in the industry. The chamber is constructed as a room-within-a-room featuring insulated, sound-absorbing walls and ceilings along with 3.3 foot thick fiberglass acoustic wedges on the interior surfaces. This design absorbs up to 99.99% of sound reflections that could otherwise interfere with sensitive audio measurements.
In 2015, Orfield Labs was recognized by Guinness World Records for achieving a background noise level of -9.4 decibels in their anechoic chamber, making it the quietest place on the planet as verified through rigorous acoustic testing. Their record has stood unmatched ever since.
Who is Steven Orfield?
Steven Orfield is an acoustic physicist and the founder, owner, and president of Orfield Laboratories. Born in 1947, Orfield developed an interest in experimental sound research starting in high school. He went on to study physics and psychophysics at the University of Minnesota, earning a bachelor’s degree followed by a master’s degree and PhD in physics psychophysics.
After school, Orfield worked at an aerospace company before deciding to launch his own business focused on acoustic and audio testing services. He established Orfield Laboratories in 1968 and began constructing the groundbreaking anechoic chamber in the 1990s based on research and academic work with acoustic tile wedges used to absorb sound.
Now in his mid-70s, Orfield continues to oversee Orfield Labs as an independent testing facility used by clients worldwide to conduct sensitive acoustic research and measurements. He holds several patents related to sound absorption and masking systems.
Inside the Anechoic Chamber
The anechoic chamber at Orfield Labs consists of a room that measures 10 feet by 12 feet and is entirely insulated from exterior sound or vibration. The walls consist of 3.3 foot thick fiberglass acoustic wedges designed to absorb up to 99.99% of sound. Even the floor is made of unique foam pads to deaden footfalls.
Small microphones installed in the chamber allow acoustic engineers to precisely measure background noise levels. In October 2015, the background noise level in the chamber was measured at -9.4 decibels, landing Orfield Labs in the Guinness Book of World Records.
Many people perceive the extreme quietness of the anechoic chamber as unsettling or even frightening. The lack of sound can highlight internal noises like heartbeat, breathing, stomach gurgling, and even ear tones, leading to a disorienting sensory experience. To alleviate this, chambers like Orfield Labs’ have a cut-off limit of 45 minutes for continuous exposure.
Uses of the Anechoic Chamber
The near complete lack of reflected sound makes anechoic chambers ideal for a range of sensitive acoustic experiments and measurements requiring controlled environments. Some of the main uses at Orfield Labs include:
– Testing consumer audio equipment like speakers and microphones across different sound frequencies. Removing reflected sound enables accurate analysis.
– Measuring sound levels emitted by devices like computers and machinery. This helps engineers reduce noise pollution.
– Evaluating acoustic shielding for aerospace and automotive uses. Sound absorption studies aid quieter design.
– Analyzing noise control materials. Echo-free space allows for precision testing.
– Psychophysics research on sensory deprivation and human hearing perception in the absence of sound.
– Product noise immunity tests, for example ensuring equipment isn’t impacted by audible frequencies.
– Benchmarking tests for audio standards like Noise Reduction Rating (NRR).
Acoustic Measurement and Metrics
To achieve superior accuracy in their acoustic measurements, Orfield Labs utilizes specialized equipment and metrics. Some key concepts include:
Decibels – The standard unit of sound measurement based on pressure levels. Higher decibel values indicate louder sounds. Normal conversation is around 60 dB.
dBA – A-weighted decibels that align sound levels with the varying sensitivity of human hearing at different frequencies. It focuses on mid-range frequencies.
Prominent frequencies – The most significant frequencies contained in a complex sound that affect perception. For example, a violin’s prominent tones are different from a tuba.
Reverberation – The persistence of sound in an enclosed space caused by multiple reflections off surfaces like walls and ceilings. Reverberation must be minimized in anechoic chambers.
Background noise level – The amount of residual noise in an environment coming from sources like air circulation that sets the lower limit on measurements. The ultra-low background level in Orfield Labs’ chamber enables more precise testing.
Verification by Guinness World Records
For a record attempt like the world’s quietest room, the process of verification by Guinness World Records is extremely rigorous. In 2015, representatives from Guinness oversaw extensive acoustic testing at Orfield Labs over multiple days to ensure the validity of their claim.
Some of the key aspects involved in certifying Orfield Labs’ record included:
– Having Guinness officials onsite to monitor the decibel measurements being taken in real-time.
– Calibrating the lab’s Bruel & Kjaer measuring equipment in front of the officials to confirm accuracy.
– Having multiple expert acousticians from both Orfield Labs and Bruel & Kjaer present throughout testing.
– Taking measurements from multiple positions within the anechoic chamber under strict supervision.
– Triple-checking results by repeating tests over the span of three days.
– Submitting detailed documentation of the test protocols, methodologies, equipment used, and results obtained during the record attempt.
– Reviewing acoustic data and calculations by Guinness’s own sound engineers to verify Orfield Labs’ claims.
This level of scrutiny was required for Orfield Labs to officially claim the record for the -9.4 dB quietness achieved in their anechoic chamber.
Significance of the Record
By achieving a background noise level of -9.4 decibels, Orfield Labs did more than just set a record. They created one of the most effective testing environments ever built for companies and researchers to work with sound.
Some key reasons why the chamber’s extreme quietness is so significant include:
– It takes sound isolation and absorption to a new level previously unattainable.
– The ambient noise level is well below the threshold of human hearing.
– It approaches total acoustic silence and anechoic conditions.
– There is no other comparable acoustic testing space on the planet.
– The lab can provide unmatched precision across countless audio tests and measurements.
– Clients have a facility to test products with no interfering noise.
– Researchers can explore hearing perception and sensory deprivation.
Comparison to Other Facilities
To fully appreciate how quiet Orfield Labs’ anechoic chamber is, it helps to compare it against some other well-known facilities:
| Location | Noise Level |
|---|---|
| Orfield Labs chamber | -9.4 dB |
| Microsoft anechoic chamber | -20.6 dB |
| Bell Labs anechoic chamber | -12 dB |
| Facebook anechoic lab | -20 dB |
| CNR Italian anechoic chamber | -21 dB |
As you can see, while major technology companies like Microsoft and Facebook have impressive sound-dampening test facilities, none achieve close to the -9.4 dB measured in Orfield Labs’ record-holding chamber. This massive gap of around 10-20 decibels demonstrates just how exceptionally silent their custom-built environment is.
Conclusion
In summary, the record for the world’s quietest room is held by the independent testing laboratory Orfield Labs, specifically their one-of-a-kind anechoic chamber custom-constructed by founder Steven Orfield. Verified extensively by Guinness World Records, the chamber provides acoustic isolation and sound absorption reaching an astonishing -9.4 dB background noise level. This makes it the gold standard site for precision audio testing, enabling clients and researchers to work in near-perfect silence. While tech giants have built their own quiet chambers, none come close to the sound-dampening capabilities of Orfield Labs’ record-holding design.