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The paper presents results of hearing loss measurements provided for 81 young people (from 16 to 25 years old). The main aim of the work was to find the influence of headphones of the types used (closed, semi-open, open and in-ear) on the hearing losses. The first part of the research was to answer questions about the influence of: time of listening, loudness of music, other noise exposures as well as the type of the headphones used. It turned out that all factors mentioned above influence thresholds of hearing but the found dependencies are not explicit. The greatest hearing losses were observed for people who work as sound reinforcement engineers and, moreover, no influence of the headphone types was found for them. It turned out that the use of in-ear headphones causes the greatest hearing losses for some subjects (thresholds shifted up to about 20 dB HL at 4 kHz). The daily time of a listening also affected the hearing thresholds. It was found that for users of in-ear and close headphones, an average time of musical exposure of three hours causes the hearing loss of 10-15 dB HL at higher frequencies. The use of open as well as semi-open headphones has no influence on the hearing damage. Thus it would be stated that these kinds are safety in use. Almost 15% of the investigated young people have their thresholds shifted up at higher frequencies, particularly at 4 kHz, which means that they have the first symptoms of a permanent hearing damage.
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ARCHIVES OF ACOUSTICS
Vol. 38, No. 3, pp. 383–387 (2013)
Copyright c
2013 by PAN – IPPT
DOI: 10.2478/aoa-2013-0045
Preliminary Study on the Influence of Headphones for Listening Music
on Hearing Loss of Young People
Andrzej B. DOBRUCKI, Maurycy J. KIN, Bartłomiej KRUK
Chair of Acoustics and Multimedia, Faculty of Electronics, Wrocław University of Technology
Wybrzeże Wyspiańskiego 27,50-370 Wrocław, Poland;
e-mail: {andrzej.dobrucki, maurycy.kin, bartlomiej.kruk}@pwr.wroc.pl
(received April 19, 2013; accepted June 18, 2013 )
The paper presents results of hearing loss measurements provided for 81 young people (from 16 to 25
years old). The main aim of the work was to find the influence of headphones of the types used (closed,
semi-open, open and in-ear) on the hearing losses. The first part of the research was to answer questions
about the influence of: time of listening, loudness of music, other noise exposures as well as the type
of the headphones used. It turned out that all factors mentioned above influence thresholds of hearing
but the found dependencies are not explicit. The greatest hearing losses were observed for people who
work as sound reinforcement engineers and, moreover, no influence of the headphone types was found
for them. It turned out that the use of in-ear headphones causes the greatest hearing losses for some
subjects (thresholds shifted up to about 20 dB HL at 4 kHz). The daily time of a listening also affected
the hearing thresholds. It was found that for users of in-ear and close headphones, an average time of
musical exposure of three hours causes the hearing loss of 10–15 dB HL at higher frequencies. The use of
open as well as semi-open headphones has no influence on the hearing damage. Thus it would be stated
that these kinds are safety in use. Almost 15% of the investigated young people have their thresholds
shifted up at higher frequencies, particularly at 4 kHz, which means that they have the first symptoms
of a permanent hearing damage.
Keywords: hearing threshold, headphones.
1. Introduction
In the past few years, the tendencies of sound
production caused an increase of loudness of sound
for communication, particularly for musical recordings.
Many radio stations as well as record companies have
applied increasing amounts of dynamic range compres-
sion and other means of the recording process in order
to be perceived in the today noisy world (Katz, 2007).
Radio stations may adjust the dynamic ranges in at-
tempt to trade off a louder sound, which may attract
listeners searching for a station. The trend called as
“loudness wars” has been reflected in the higher sub-
jective impressions in the psychological domain, and
the slogans “louder means better” and “louder sounds
are sold better” have come true (Vickers, 2011).
Many young people want to separate their minds of dif-
ferent backgrounds by the use of special kinds of head-
phones and they listen to the sound material louder,
beside of the fact that the listened material is louder in
comparison to the recordings made in the previous cen-
tury. The contemporary designed and produced equip-
ment allows the listeners to consume music in accor-
dance with their way of life. On the other hand, young
people say: we listen to the music that sounds nicely
for us and it is not alike as noise, so why may it be
dangerous for our hearing? Sometimes, one could find
many pieces of classical music from the XXth century,
which are very loud while performed. The main differ-
ences between classical and pop-music are in the time
of continuous exposition to the sound, the character
of musical structure and spectral consistence of stim-
uli. In popular music, the way used very often during
musical production process is based on the sound com-
pression, and this compression itself may increase the
potential for hearing damage. Moreover, the way of
stimuli presentation (via headphones or loudspeaker,
or naturally listening to the event) seems to be an im-
portant thing causing the hearing loss. Young people
do not take into account that popular or rock music
384 Archives of Acoustics Volume 38, Number 3, 2013
causes effects like that of higher and longtime expo-
sure to noise when the earphones are used for listening
due to the average sound level and duration of expo-
sure, which simply leads to a listening fatigue (Moore,
1997). Of course, the higher hearing thresholds induce
difficulties in receiving many information from human
environment that influences the sense of safety and
causes changes in the way of thinking and living to-
gether in a society (Strelau, 2000). It also may be
interesting while the European Standard EN ISO 7029
still remains actual in the light of youngsters’ way of
life and this aspect was the aim of the research pre-
sented.
2. Experimental research
The results of audiometric measurements of 81
young people aged between 16 and 25 years are pre-
sented. The subjects declared frequent listening to loud
music on headphones. None of them complained of
hearing problems. The participants were asked to fill
out the questionnaire sheet and to answer the following
questions: the type of the used headphones, the daily
listening time, the preferred levels of listening and the
kind of music. Additionally, they have to point on other
conditions concerning the noise exposure at the work,
the background noise connected with the place of liv-
ing, the work activity etc. The research was made for
the inhabitants of Wroclaw.
Some of the people under investigation are working
for an entertainment industry in a professional way
so they were divided into three groups reflecting their
activities:
young classical musicians or music academy stu-
dents,
sound reinforcement engineers of FOH/PA sys-
tems (Front of House / Public Address sound sys-
tem),
sound engineers working in recording studios.
The ordinary young users of portable audio equip-
ment were representative as the reference group for
this range of age.
Characteristics of the study population obtained on
the base of the questionnaires are as follows:
81 people (including 26 women),
the average age: 22.5 years (between 16 and 25),
average daily time of using of the headphones:
32 h (from 2 to 7 hours, 1 person declared 14
hours),
other noise exposures: 4.9 hours per week (for ex-
ample loud rock concerts).
The noise exposure occurred in the group of profes-
sionals.
According to the questionnaires, taking into ac-
count the subjects’ activities, the whole group of the 81
persons was divided into the following four subgroups:
young classical musicians or music academy stu-
dents (26 people including 10 women),
sound engineers of FOH/PA systems (10 men
only),
sound engineers working in recording studios (11
people including 3 women),
users of audio equipment involved not profession-
ally with the entertainment industry (34 people,
including 13 women).
The first three subgroups were considered later sepa-
rately.
The young musicians usually practice individually
being exposed to noise for a long time (up to 8 hours
per day). An equivalent level weighted during practic-
ing with Acurve that does not exceed 70 dB and is not
harmful to hearing. On the other hand, this an impor-
tant fact in their work is a symphony orchestra in that
the rehearsal unweight peak levels can be as high as
110 dB SPL and the equivalent level Amay be even of
85 dB. These are facts often overlooked and very reluc-
tantly discussed by directors of operas and symphony
orchestras due to the damages for musicians.
The second type of division of the whole population
is defined by different types of earphones used by the
subjects as declared in questionnaire what resulted in
four subgroups:
in-ear headphones – 23 users,
open headphones – 18 users,
closed – 22 users,
semi-open – 18 users.
In this case each group consists of almost the same
number of women and men. The most of the subjects
(80%) declared that they listened to very loud music
and the daily time of the headphone use was 3.2 h,
which results in a weekly exposure of more than 22 h.
The results of the questionnaires did not allow indicat-
ing any other factors that could influence the hearing
threshold values because of their different representa-
tives within each subgroup.
After the interviews and spoken instructions the
people were measured by means of audiometers. The
audiometric tests were conducted in an anechoic cham-
ber and in the recording studio of the Wrocław Uni-
versity of Technology. These places meet the require-
ments of a maximum allowable amount of the back-
ground sound pressure level (ISO 8253-1:2010). There-
fore, during the tests any masking phenomenon from
outer signals does not occur (PN-EN 26189, ISO 8253-
1:2010, ISO 7029:2000). Before the measurements, all
the audiometers had been basically calibrated and
checked aurally, they had also been calibrated subjec-
tively in accordance with the ISO recommendations
(PN-EN 26189). The threshold of hearing levels were
determined by the air conduction audiometry with the
A.B. Dobrucki, M.J. Kin, B. Kruk Preliminary Study on the Influence of Headphones. . . 385
Maico M 53 audiometers. The measurements were car-
ried out according to the applicable standards (PN-
EN 26189) by ascending methods and with the use of
continuous sinusoidal signals with steps of 2 dB. All
measurement points were repeated twice in order to
eliminate random errors for inexperienced subjects.
3. Analysis of the results
3.1. Average hearing threshold
Figure 1 shows the values of the hearing thresh-
old for the left and right ears of the population tested.
These values have been averaged over results obtained
for 81 listeners. It can be easily seen that the thresh-
old of hearing is uniformly shifted by about 6–7 dB.
The statistical treatment by means of the Bartlett test
(Greń, 1978) showed that the variances of the re-
sults obtained were homogenous (χ2= 24.893 < χ2
α=
39.977, at α= 0.05) for all frequencies.
Fig. 1. Average values of the threshold of hearing (dB HL)
for the tested population.
According to classification of BIAP (BIAP Rec-
ommendation 02/1), the young people tested belong
to the group of normal hearing, but the shift in the
threshold of hearing points to a slow tendency of the
beginning of a permanent damage of hearing. These
values, however, are the average ones and the great-
est hearing losses can be balanced by the results for
the people with otological normal values shown in Ta-
ble 1 as values of standard deviations, especially for
higher frequencies. Thus, it was decided to divide the
whole group into categories which could influence the
Table 1. The average values and standard deviations for
hearing thresholds (dB HL) for the left and right ears,
respectively, measured for all of 81 subjects.
Frequency [Hz] 250 500 1000 2000 4000 8000
xL5.1 6.0 6.5 5.8 6.4 6.7
σL7.2 6.9 6.1 6.6 10.2 11.1
xR5.7 6.0 6.5 5.6 5.9 7.3
σR5.5 6.4 5.7 7.4 11.5 10.8
obtained results and reflect the real hearing loss for
some specific nature of work as well as kinds of equip-
ment used by the people.
3.2. The influence of different kinds of headphones
on the threshold of hearing
In this section, the results of pure tone audiometry
for users of different types of headphones are presented.
These results present “the worse” ear (left or right) for
each subject and these values have been averaged over
the people which use particular types of headphones.
They are shown in the Fig. 2.
Fig. 2. Influence of different kinds of headphones on the
threshold of hearing (dB HL). Standard deviation values
are presented as vertical lines on the tops of the bars.
It turned out that except for the frequency of 4 kHz
there is no relationship between the types of the pre-
ferred headphones and the shift of the hearing thresh-
olds (F < Fα= 2.75, where F,Fα– calculated and
critical values of the F-Snedecor test, respectively, at
α= 0.05). For the frequency of 4 kHz, a statisti-
cally important influence of the headphone type on the
threshold values was observed (F= 3.35 > Fα). This
means that most unfavorable for the hearing are in-
ner earphones, especially at high frequencies for which
our hearing system is most sensitive. The air in the
ear canal is a natural protection from high sound pres-
sure. Using inside earphones the length of the channel
is reduced whereby the natural protection becomes less
effective and the sound level in ear channel increases
by 6 dB. Good alternatives are semi-open headphones
that in a small way can isolate us from the outside
noise. They additionally ensure good hygiene of the
ear and by their design they are a protection from
very high sound pressures acting directly on the ear
membrane. The results of the hearing threshold values
obtained for the frequency of 4 kHz are presented in
Table 2.
Table 2. The average values of hearing thresholds at
4 kHz for various types of headphones, in dB HL.
Type of headphones in-ear open closed semi-open
Hearing threshold
[dB HL] 9.2 3.9 2.9 0.1
386 Archives of Acoustics Volume 38, Number 3, 2013
In order to determine how the particular kinds of
headphones are injurious for listening conditions, the
structure index test (Greń, 1978) was applied as a
statistical treatment for the series which reflects the
degree of the hearing damage caused by the type of
the used headphones, with uα= 1.96 at α= 0.05. It
turned out that for the frequency of 4 kHz the most
dangerous for the hearing threshold is the inner-ear
headphone type (|u|= 4.73), while the influence of the
semi-open type is statistically inessential (|u|= 1.05 <
uα). The degrees of injuries of the hearing damage
obtained for the open and the closed headphones are
lower than those for the in-ear headphones (|u|= 2.52
and |u|= 2.12, respectively).
3.3. Threshold of hearing in terms
of professional work
In this section, only the professional group is ana-
lyzed (the three first subgroups listed in Sec. 2). The
number of people in this group is equal to 47. Among
them 35 persons have been working in the profession
up to 7 years. By analyzing these data it can be con-
cluded that even 3–4 years of working at an entertain-
ment industry, especially as the front-of-house engi-
neers may cause a slight loss of hearing ability. Com-
paring the other professional groups, it can be assumed
that the results coincide to a large extent and the type
of work (noise level) have no longer such effect on the
threshold of hearing. In Fig. 3 hearing thresholds de-
pending on the profession are presented. These results
present “the worse” ear (left or right) for each subject,
and these values have been averaged over the people
within the particular group of profession.
Fig. 3. Thresholds of hearing (dB HL) depending on the
profession. Standard deviation values are presented as ver-
tical lines on the tops of the bars.
As in the previous case it was decided to use the
single-factor statistical treatment and on the base of
the analysis of variance, it turned out that for fre-
quency values of 500 Hz, 1 kHz as well as 4 kHz an in-
fluence of the working activity on the threshold of hear-
ing has been observed (F > Fα= 3.29, where F,Fα
calculated and critical values of the F-Snedecor test,
respectively, at α= 0.05). For other frequencies there
is no relationship between the profession of work and
the shift of the hearing threshold values. As mentioned
in the previous chapter, the hearing loss at 4 kHz can
be interpreted as the beginning of a permanent hear-
ing damage that results from the exposure to sounds at
high levels while the upward threshold shifts appear-
ing for lower frequencies (500 Hz and 1000 Hz) result
from the exposure to hyper-compressed musical sounds
in these frequency bands, especially occurring on the
stage situation in order to increase the total loudness
impression.
4. Conclusions
On the base of the results presented it would be
fairer to say that the most dangerous kind of head-
phones is the in-ear headphone set which causes the
upward threshold shift of 9 dB HL at the frequency
of 4 kHz. When the music would be played very loud
and as long as declared at a level of approximately
100 dB SPL, a permanent hearing damage will oc-
cur after no more than 4 years of using such devices.
Another factor influencing the hearing condition sys-
tem is the professional activity connected to the expo-
sure to loud signals. The presented results have also
shown that working as reinforcement engineers with
FOH/PA systems can permanently destroy the hear-
ing system because an activity as long as 3–4 years
causes the upward threshold shifts even of 16 dB HL
at 500 Hz and 4 kHz. These values may mean the be-
ginning of a permanent hearing damage and have to be
taken into consideration by the industrial health pro-
tection. The results of the other researches (Chiou-
Jong et al., 2007; Gulati, 2011) conclude that it is
enough to listen to loud music on MP3 players one
hour a day for five years to ruin the hearing system
permanently.
Hearing care professionals skeptical to listening to
music with headphones admit that only a moderate
volume for up to 8 hours a day is no longer a risk of
hearing loss.
It was clearly shown what kind of problems we are
dealing with. Listening to music is becoming a dis-
ease primarily among young people, but this fact is
ignored in the media. The biggest problem is the type
of headphones used for the every day listening. Most of
young people listen to music through inside earphones
what causes that the length of the ear canal is reduced,
and as a consequence, the natural protection becomes
less effective. The body does not give us a sign that
the process of destroying the hearing has just began,
and once damaged the hearing cells would never rege-
nerate.
From the sociological point of view, young people
like this kind of earphones because they take up little
space and can be always carried in a pocket, however
on the other hand, they are the worst ones for our hear-
A.B. Dobrucki, M.J. Kin, B. Kruk Preliminary Study on the Influence of Headphones. . . 387
ing. Research has shown that 2–3 years of using this
type of headphones leads to a slight hearing damage
resulting in an incomprehensibility of whisper or quiet
voice.
References
1. BIAP Recommendation 02/1 bis: Automatic classifica-
tion of hearing impairment, Oct. 26, 1996.
2. Chiou-Jong Ch., Yu-Tung D., Yih-Min S., Yi-
Chang L., Yow-Jer J. (2007), Evaluation of Audi-
tory Fatigue in Combined Noise, Heat and Workload
Exposure, Industrial Health, 45, 4, 527–534.
3. Gulati S. (2011), Hearing loss from headphones and
earphones, http://www.symptomfind.com/health/he-
aring-loss-from-headphones.htm.
4. Greń J. (1978), Mathematical Statistics. Models and
Exercises [in Polish], PWN, Warszawa.
5. ISO 7029:2000, Acoustics Statistical distribution of
hearing threshold as a function of age.
6. ISO 8253-1:2010, Acoustics – Audiometric test methods
– Part 1: Pure-tone air and bone conduction audiome-
try.
7. Katz B. (2007), Mastering Audio: The Art and the
Science, Focal Press, Oxford.
8. Moore B.C.J. (1997), An Introduction to the Psychol-
ogy of Hearing, Academic Press, London.
9. PN-EN 26189, The measurements of hearing threshold
by audiometric air conduction for hearing protection
[in Polish].
10. Strelau J. (2000), Psychology [in Polish], Gdańskie
Wyd. Psychologiczne, Gdańsk.
11. Vickers E. (2011), The Loudness War – Do Louder,
Hypercompressed Recordings Sell Better?, J. Audio
Eng. Soc., 59, 5, 346–352.
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The paper presents results of research on an influence of Temporary Threshold Shift (TTS) on the detection of changes in timbre of musical samples. The experiment was carried out with conditions which normally exist in a studio when sound material is recorded and mixed. The level of sound exposure which represents the noise signal is 90 dB and this is an average value of sound level existing in control room. This musical material may be treated as a noise so TTS phenomenon may occur after several time durations: 60, 90 and 120 minutes. Ten subjects participated in the main part of the experiment and all of them have the normal hearing thresholds. The stimuli contained the musical material with introduced changes in timbre up to +1-6 dB in low (100Hz), middle (1kHz) and high frequency (10kHz) regions. It turned out that listening to the music with an exposure of 90 dB for 1 hour influences the hearing thresholds for middle frequency region (about l-2kHz) and this has been reflected in a perception of timbre changes: after 1 hour listening the changes of spectrum in middle-frequencies region are perceived with a threshold of 3 dB while the changes of low and high ranges of spectrum were perceived with the thresholds of 1.8 and 1.5 dB, respectively. After the longer exposure, the thresholds shifted up to 3.5 dB for the all investigated stimuli.
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Toys emitting sounds are classified as significant sources of noise found in the children environment. Impulse and continuous noise emitted by toys, used in close to the child’s ear, acting directly on the organ of hearing, can lead to serious adverse health effects. This is especially true for children under the age of three, in which the state of the hearing organ determines their intellectual development. The current level of safety of sound emitting toys intended for children in this age group is insufficient. This is confirmed by the reports from the control of market surveillance authorities. A new approach to the assessment of children’s exposure to noise generated by toys, included in EN 71-1:2011 + A2:2013 Standard, based on the permissible values applicable to the workplaces, requires further tests and verification. The paper presents the results of the research work and assesses the level of sound emitted by toys in the light of current standard requirements, carried out using the author’s methodology. Toys intended for children under the age of 3 years, commercialized on the European market by Polish manufacturers and importers were tested. The results of the tests allowed us to determine the impact of duration of the sound pressure level measurement on the final result.
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This study was performed in a climatic chamber to evaluate the combined effects of noise intensity, heat stress, workload, and exposure duration on both noise-induced temporary threshold shift (TTS) and the recovery time by adopting Taguch's method. Fourteen subjects without previous significant noise exposure and smoking history were recruited to participate in this study. All hearing threshold levels at eight different frequencies (250 to 8,000 Hz) of better ear were measured in an audiometric booth by using the ascending method in 2 dB steps before each exposure condition. The test was also carried out after exposure to evaluate TTS at various times. The TTS recovery time was assessed using an audiometric test on all subjects at post-exposure times of 2, 20, 40, 60, 80 and 120 min, respectively. It was found that TTS depended mainly on the exposed noise dose and was enhanced by workload and heat stress. The TTS recovery time is dependent upon the magnitude of the initial hearing loss. In conclusion, TTS driven by noise exposure is enhanced by heat and workload. Further studies are required to evaluate the effects of workload with extreme temperature in a workplace environment.
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The term "loudness war" refers to the ongoing competitive increase in the loudness of commercially distributed music. While this increase has been facilitated by the use of dynamic range compression, limiting, and clipping, the underlying cause is the belief that louder recordings sell better. This paper briefly reviews some possible side effects of the loudness war and presents evidence questioning the assumption that loudness is significantly correlated to listener preference and sales ranking.
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Text: book; for undergraduates and others studying sound and auditory perception. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Mathematical Statistics. Models andExercises [in Polish
  • J Greń
Acoustics Statistical distribution ofhearing threshold as a function of age
  • Iso
Hearing loss from headphones andearphones
  • S Gulati
Acoustics – Audiometric test methods – Part 1: Pure-tone air and bone conduction audiome- try
ISO 8253-1:2010, Acoustics – Audiometric test methods – Part 1: Pure-tone air and bone conduction audiome- try.
  • J Strelau
Strelau J. (2000), Psychology [in Polish], Gdańskie Wyd. Psychologiczne, Gdańsk.
Acoustics Statistical distribution of hearing threshold as a function of age
  • J Greń
Greń J. (1978), Mathematical Statistics. Models and Exercises [in Polish], PWN, Warszawa. 5. ISO 7029:2000, Acoustics Statistical distribution of hearing threshold as a function of age.