Hearing Health Affecting Critical Listening

A healthy auditory pathway provides the audio engineer with the best opportunity to listen critically, which in turn guides their choices. There is currently no way to precisely predict the susceptibility to damage that loud sounds pose to a particular person.
Hearing conditions affecting critical listening include:
  • ​acoustic shock - damage to the auditory system caused by high sound pressure and exposure,
  • tinnitus - (more details below),
  • hair cell damage causing a loss in sensitivity, often beginning around 4k and then spreading to adjacent frequencies,
  • diplacusis - hearing one tone as two tones of different frequencies in each ear up to 15% difference, (listen to the video example)
  • distortion of tones,
  • ruptured eardrum,
  • presbyacusis - age-related high-frequency loss, where the perception of higher frequencies reduces as we age,
  • PTS - permanent threshold shift - which is a permanent loss of hearing at particular frequencies,
  • Meniere’s disease - is an inner ear disease, causing vertigo, dizziness, balance issues, tinnitus and pitch perception,
  • physiological changes affecting auditory perception - can be a reduced sensitivity to weak sounds, or 'loudness recruitment' where the sensitivity to some loud sounds increases, the effects of which reduce the accepted dynamic range and may also affect the ability to perceive pitch accurately, and
  • disruption to the auditory pathway between the cochlear hair cells and the brain which can be caused by long-term noise exposure.
Diplacusis Demo

Tinnitus

Tinnitus is the term used for a noise that is heard but does not come from an outside source. Tinnitus is often described as a ‘ringing in the ears’ but can be experienced in other ways, like a buzzing or hissing, waves, cicadas or even a thumping sound. It can be faint or loud, constant or occasional, steady or pulsing. The effects can range from not bothersome to very annoying. Tinnitus is more noticeable in quiet times, at night or when tired or stressed.
​The risk of tinnitus is twice as high in musicians compared to the general population, with 50% of professional musicians reporting tinnitus. In one investigation, more than two-thirds of live-sound respondents reported tinnitus as the most common effect of changes in their hearing, followed by a loss of response to specific frequencies. The video below demonstrates what tinnitus sounds like to some people:
Tinnitus affects:
  • 34% of audio engineers
  • 54% of percussionists,
  • 57.6% of professionals versus 44.2% of amateurs,
  • 60% of violinists in one ear only, and
  • 24 - 30% of orchestra musicians find tinnitus bothersome and 6% highly bothersome.

Other Hearing Loss

In one study, sixty-nine pop musicians, four disk jockeys, four managers, and six live sound engineers, had their hearing tested. From these participants, the right-top image (below) is an audiologist's pure-tone audiogram displaying their average hearing response. An individual with this shaped audiogram is said to have ‘MILD’ hearing loss. An earlier study among audio engineers found that 10% of the participants demonstrated moderate to severe hearing loss at around 4000 Hz. This audiogram would concur with that previous study. ​In a more audio engineer-recognisable format, the right middle parametric EQ curve demonstrates the frequency loss represented by the audiogram in the right-top image. The right-bottom curve illustrates the frequency compensation required to make up for the loss. How would implementing the 'MILD' hearing loss EQ curves shown here affect a given sound? Could these examples explain why some audio engineers’ 'mixes' contain significant high-frequency content?
Pure Tone Audiogram Average Comparison to a healthy 18 - yr-old's hearing
Audiogram displayed as an EQ curve
Audiogram as an EQ curve with frequency loss compensated
N0rmal
Voice Over - normal track
Mild Hearing Loss (MHL)
Voice Over - mild hearing loss
MHL Compensated
Voice Over - compensating for mild hearing loss
Listen - normal track
Listen - mild hearing loss
Listen - compensating for mild hearing loss
SoS - normal track
SoS - mild hearing loss
SoS - compensating for mild hearing loss

Facts, Statistics and Effects

The audio engineer is a musician whose instrument is their mixing technology. ​The following statistics provide a useful audio engineer reference:
  • 1.1 billion young people have some form of music-induced hearing loss.
  • Over 50% of professional musicians have hearing loss, mostly around 4-6 kHz.
  • Musicians are four times as likely to experience noise-induced hearing loss than non-musicians.
  • 68-74% of pop/rock/jazz musicians have hearing disorders.
  • Percussionists and brass players have the worst hearing thresholds of all musicians.
  • Hearing loss tends to be more prevalent in male musicians than female musicians.
  • Diplacusis is present in 18% of musicians, 5% in orchestra players. Diplacusis produces a notably different perception of a single frequency tone in the two ears of up to 15-20%. A 200 Hz tone in one ear may sound like 240 Hz in the other ear.
  • 24% of musicians, 12% being orchestra players, report a distortion of tones, overtones and harmonics where these appear unclear, fuzzy or out of tune.
  • 39-79% of musicians report hyperacusis. Women report a higher rate than men, compared to 15% of the general population..
​Asymmetry
Male jazz or rock musicians who play in amplified sound environments report significantly weaker hearing thresholds in their left ear. Amongst classical orchestral musicians, violinists, violists and drummers may have reduced hearing ability in their left ear, while flute and piccolo players may have reduced hearing ability in the right ear. A flautist may still have reduced hearing ability in their left ear due to the location of trumpet players on their left side.

Good News!!!

50% of musicians and 43% of audio engineers have found ways to work in a noisy industry without ​experiencing hearing damage!

Other Health and Social Effects

While not all hearing damage is the result of acoustic trauma, the effects of reduced hearing function are also not just restricted to hearing processes and include:
  • headaches,
  • nausea,
  • balance issues,
  • anxiety,
  • hypersensitivity,
  • fatigue,
  • depression,
  • insomnia,
  • declination of cognitive ability,
  • reduced performance ability
  • social isolation,
  • fluttering in the ear,
  • effects on concentration and morale,
  • mitochondrial DNA damage​
Masked Recovery
In the days following a concert, our hearing may seem to have recovered from any threshold shift, where the shift is no longer significant. What may take longer to recover from, possibly over a period of a week or two, is the ability to perceive words in noise.
Financial Cost
The estimated total financial cost of hearing loss within NZ in 2016 was NZ$4.9 billion, with the cost to the NZ economy at NZ$957.3 million. These figures present a cost to each New Zealander of NZ$5556 in contributions toward assisting individuals with hearing loss issues.​Of persons aged 12–35, 50% are at risk of hearing loss due to exposure to unsafe levels of sounds in recreational settings. 1.5 billion people experience hearing loss, and this figure could grow to 2.5 billion by 2050. Without intervention, the global economy is estimated to lose close to one trillion dollars each year. WHO estimates that investing in ear care and hearing management could bring a return of sixteen dollars for every dollar spent. LINK to WHO World Hearing Report
SC - Monitor Engineer CSO Pitrates of the Caribbean
How [do you] tell a loved one they’re coiling cables wrong?
TOM K
Stephen Compton
PhD| MA | BA (Hons) Recording Arts |Dip. Sound Engineering |Trade Certificate AV Production | Theatre and Live Sound| Music Technician | Audio Education | Acoustic Consultant
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