Simcenter Testing Solutions Describing Sounds with Words

Ever tried to describe the unusual sound a product makes with words?  Check out this reference (with example sounds) to decide the best word to describe what you are hearing. 

These words are commonly used in Noise and Vibration (NVH) engineering. 
 
Words are listed in alphabetical order below.  Be sure to use quality headsets to hear the full frequency range of the sounds.  Playback through inexpensive headsets and laptop speakers often do not fully reproduce the sounds. 

 

Word (Click to Listen)	Description	Example	Additional Information
	Broadband sounds have somewhat equal amplitude at all frequencies. No single frequency or tone "sticks out" above the others.	Road and wind noise are common examples of broadband sound in a vehicle.	White and pink noise broadband examples
	High frequency noise that sounds like a bird chirping.	Pulley misalignment issues in a belt driven system can create chirping noise.	Tone-to-Noise ratio and prominence ratio
	Short duration, high frequency noise. Sounds like clicking on a ball point pen.	Short duration metal on metal contact (door slam, transmission shifter, etc). Making the duration of contact longer (by wrapping the metal in plastic or rubber) lengthens the contact and lowers the frequency range.	Wavelets, kurtosis
	Low frequency noise that sounds like animal growl.	Combustion engine under heavy load can produce growl.	Modulation metrics
	Hoot is a sudden unexpected high pitched sound similar to the that of an owl.	When the frequency of the pressure waves match a resonance of air volume inside an exhaust system, a hoot noise occurs.	Natural frequency and resonance
	A lugging sound rises and falls over time, instead of being constant level.	An electric motor that binds while operating starts to make a lugging sound.	Fluctuation strength sound metric
	This sound is a word!	Calculate a colormap of this sound to see the mystery word. Download mystery.ldsf or mystery.wav to analyze.	Simcenter Testlab Throughput Processing Tips
	A ping is a transient noise with high frequency content that takes some time to decay.	Pinging noises might be heard from a hot exhaust system system as it cools down and the metal contracts. Another example is golf club hitting a ball.	Kurtosis
	Broadband sound where all octave bands have the same level.	An artificial sound used in noise testing.	Octaves and human hearing
	When two items hit each other repeated that contain loose parts.  When done repeatedly over time sounds like a baby rattle being shook.	In transmissions, the unengaged gears can vibrate and hit each other repeatedly, causing rattle.	Interpreting colormaps article with section on gear rattle
	Low frequency sounds that rise and fall many times per second. Sound is said to be modulated.	Sporty sounding vehicles are said to have a degree of rumble in the exhaust note.	Roughness sound metric
	A shrill or sharp sound has significant amounts of high frequency content.	Sounds large amount of high frequency content are often considered shrill. For example, a vacuum cleaner with high frequency content rather than low frequency tones.	Sharpness sound metric
	Sound made by liquid flowing back and forth in a container.	Stopping a vehicle can cause the fuel in the fuel tank to shift, which creates a sloshing noise.	Baffles in fuel tanks reduce slosh noise.
	Short duration, high frequency, sound.  Dominated by a single frequency.	Brake squeal is caused by non-linear behavior of brake system: self-excited vibration drawing energy from the braking action.	Tone-to-Noise ratio and prominence ratio
	Sound like a sewing machine or a clock. A steady stream of short duration tick sounds.	Fuel injectors in engines making ticking sounds as they release fuel.	Kurtosis
	When a single frequency is much higher than surrounding frequencies, a sound is said to be tonal.	Mosquitos make tonal sounds!	Tonality
	Tonal high pitch sound.	Gears meshing in a transmission often create whine. Noticeable on electric cars that have no combustion engine noise masking.	Tonal sound metric seminar
	Broadband noise where all frequencies are at same level. Similar to the sound of a waterfall.	An artificial sound used in noise testing.	White noise is an artificial broadband noise
	Rapidly changing high frequency metallic sound, like a zipper.	Gears that rapidly spin back and forth (example: electric power steering system) can produce zipper noise.	Interpreting colormaps article with section on gear meshing

 
Know of other types of sounds that would be included? Feel free to let us know! Post a comment or email Scott MacDonald (macdonald@siemens.com).

Related Links:

• Index of Testing Knowledge Articles
• History of Acoustics
• Sound Pressure
• What is a decibel?
• What is A-weighting?
• Octaves and Human Hearing
• Loudness and Sones
• Sound Intensity
• Articulation Index
• Speech Interference Level
• Calculating a Specific Loudness Spectrum in Simcenter Testlab
• How to Calculate N10 Time Varying Loudness in Simcenter Testlab?
• Auditory Masking
• Tonality
• Tone-to-Noise Ratio and Prominence Ratio
• Fluctuation Strength and Roughness
• Simcenter Testlab Neo: Modulation Metrics
• Sharpness
• Critical Bands in Human Hearing
• Kurtosis
• Simcenter Testlab Pass-by Noise Testing
• Sound Quality Jury Testing
• Alter Speed of Rotating Sound for Listening
• Simcenter Testlab Sound Diagnosis
• NVH Testing and Data Acquisition
• Sound Quality Metrics Unleashed Seminar
• Tonal Sound Metric Seminar
• Sound Quality Jury Testing Seminar
• Sound Quality YouTube Playlist