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Supra-aural and circumaural earphones. A photograph of a supra-aural (Telephonics TDH-39P) earphone is shown on the left. A circumaural (Sennheiser HDA200) earphone is shown on the right. The supra-aural earphone enclosure rests on the listener’s pinna during testing. The cushion on the circumaural earphone enclosure forms a seal around the periphery of the pinna but does not rest on the pinna during testing. 

Supra-aural and circumaural earphones. A photograph of a supra-aural (Telephonics TDH-39P) earphone is shown on the left. A circumaural (Sennheiser HDA200) earphone is shown on the right. The supra-aural earphone enclosure rests on the listener’s pinna during testing. The cushion on the circumaural earphone enclosure forms a seal around the periphery of the pinna but does not rest on the pinna during testing. 

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Article
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Objective: This study examined differences in thresholds obtained under Sennheiser HDA200 circumaural earphones using pure tone, equivalent rectangular noise bands, and 1/3 octave noise bands relative to thresholds obtained using Telephonics TDH-39P supra-aural earphones. Design: Thresholds were obtained via each transducer and stimulus conditio...

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Context 1
... audiometry was one of the first methods established for the measurement of hearing sensitivity (e.g. Fletcher & Wegel, 1922), and it remains the gold standard procedure (Engdahl et al, 2012). The threshold audiogram provides frequency-specific comparisons of a listener’s response against the responses that would typically be expected from a young population with normal hearing (i.e. 0 dB hearing level, or HL). Band-limited stimuli are necessary to provide frequency-specific information, and pure tones were initially adopted because they represent the minimum possible bandwidth and are easy to generate. The reliability of pure-tone thresholds obtained using the TDH-39P supra-aural earphone ( Figure 1) is poorer in the high frequencies (Flamme et al, 2014) where stimulus wavelengths are comparable to the distance from the transducer diaphragm to the eardrum and standing waves are possible. In addition, ringing in the ears (i.e. tinnitus) tends to have a tone-like quality that can be confused with the tone, which complicates the interpretation of pure-tone test results for listeners with tinnitus. Regular audiometric monitoring is a key component of hearing conservation programs. The purpose of monitoring audiometry is to identify changes from baseline threshold and quickly determine whether the change is associated with excess exposure to noise or other ototoxicants before any change in hearing interferes with performance in daily life. High reliability, therefore, is crucial to the task of identifying changes in hearing sensitivity as early as possible. The reliability of pure-tone threshold audiometry with TDH-39P earphones is moderately good, but improvements in reliability in the high frequencies are desired (Flamme et al, 2014). The attenuation of hearing protectors is conventionally measured using the differences between thresholds with and without the protection device in place. High reliability of the measurement is also important for hearing protector measurements. Narrow bands of noise have long been used as the preferred stimuli for assessment of hearing protector attenuation, partly due to the common need to test hearing protectors in sound fields where a uniform sound field for tonal stimuli would be nearly impossible. Lab measurements of earplug attenuation tend to overestimate the amount of attenuation observed among workers in practice (Berger et al, 1998). This could be partly due to differences in training or motivation, and partly due to the application of research ...
Context 2
... cannot be duplicated in the field. However, field-based systems for checking the attenuation of hearing protectors have been developed (Murphy, 2013) using high-quality low-cost audio systems (e.g. laptop sound cards, tablet computers), and the technical requirements of those systems can be similar to the technical requirements for threshold audiometry. It is possible to devise a field-based system that combines audiometric monitoring and indi- vidualized assessment of earplug attenuation into a low-cost and efficient procedure. Such a system would, necessarily, use instru- mentation and procedures capable of assessing occluded and unoc- cluded thresholds. At a minimum, this requirement implies the use of circumaural earphones for assessing the attenuation of earplugs. Further, this system should also produce results comparable to conventional pure-tone thresholds and measures of hearing protector attenuation. The Sennheiser HDA200 earphones (Figure 1) are an example of a circumaural earphone style. The increased bandwidth of noise stimuli could reduce the extent to which narrow frequency regions of reduced audibility are observed, which may lead to underestimates (i.e. artificial improvements) in threshold on steeply-sloped segments of the audiogram. The pure- tone stimulus primarily excites the portion of the basilar membrane surrounding the pure-tone frequency. However, the auditory filter is spread continuously about the point that serves this frequency. The equivalent rectangular band (ERB, Glasberg & Moore, 1990) is intended to represent a rectangular filter shape that has the same area as the auditory filter. Auditory filter measurements suggest that the shape of the auditory filter follows a rounded exponential or compressive gammachirp curve (Unoki et al, 2006). Given that a stimulus with a rectangular spectrum is used to approximate a non-rectangular auditory filter shape, it is possible that neighboring auditory filters could be excited by rectangular bands, and responses from adjacent auditory filters could lead to apparent improvements in sensitivity, if better sensitivity is present in the adjacent filters. This would result in an apparent ‘filling’ of audiometric notches, which would be exhibited by reduced absolute slope between neighboring frequencies. One-third octave band (1/3 OB) signals have also been used to obtain frequency-specific threshold information (e.g. Cox & McDaniel, 1986). One could expect that 1/3 OB signals would reduce slopes between neighboring audiometric frequencies more than ERB signals because the ERBs are narrower than 1/3 OB signals. This study had three objectives. The first objective was to determine whether thresholds obtained with the HDA200 earphones using noise bands are exchangeable, or can be transformed into, equivalent pure-tone thresholds obtained with TDH-39P supra- aural audiometric earphones. The second objective was to determine whether thresholds obtained with HDA200 earphones result in sub- stantially different reliability than pure-tone thresholds obtained with conventional supra-aural audiometric earphones. Finally, we conducted an exploratory assessment of whether the use of noise bands influenced the slope of the audiogram in cases of large threshold changes between neighboring frequencies. These objectives contrib- ute to a long-term goal of evaluating the feasibility of conducting audiometric monitoring and field testing of earplug attenuation using a single stimulus and earphone model. The participants in this study were a subset of 49 participants who previously completed a larger study of the reliability of pure-tone thresholds (Flamme et al, 2014). Participants who completed the prior study were divided into three reliability groups (high, medium, low) of equal size, based on mean squared deviation from the mean threshold (across ears, stimulus frequencies, and a total of ten sepa- rate tests). Participants were selected on the basis of known threshold reliability in order to ensure generalizability of results to the population. Invitations to participate in the current study were issued to obtain approximately equal numbers of men and women in each reliability category, which led to a study sample of 26 men and 23 women. Participants were between 20 and 69 years of age, and the majority (60%) of the sample was between 40 and 59 years old. A total of 11 participants were between the ages of 20 and 39, and eight participants were between the ages of 60 and 69 years of age. No systematic relationship between decade of age and ...

Citations

... The authors call it the "good enough bias." The transducers used to determine the manual thresholds could also impact the results at the higher frequencies because of geometric interactions with the individual subject ears, as has been found previously (Bhatt, 2018;Flamme et al., 2015;Frank, 2001;Han and Poulsen, 1998). However, one important outcome of computing the RETSPLs of a new transducer is to ensure that thresholds measured by different devices are equivalent and can be interpreted in the same way regardless of the measurement system. ...
Article
This paper presents reference equivalent threshold sound pressure levels (RETSPLs) for the Wireless Automated Hearing Test System (WAHTS), a recently commercialized device developed for use as a boothless audiometer. Two initial studies were conducted following the ISO 389-9 standard [ISO 389-9 (2009). "Acoustics-Reference zero for the calibration of audiometric equipment. Part 9: Preferred test conditions for the determinations of reference hearing threshold levels" (International Organization for Standardization, Geneva)]. Although the standard recruitment criteria are intended to yield otologically normal test subjects, the recruited populations appeared to have slightly elevated thresholds [5-10 dB hearing level (HL)]. Comparison of WAHTS thresholds to other clinical audiometric equipment revealed bias errors that were consistent with the elevated thresholds of the RETSPL populations. As the objective of RETSPLs is to ensure consistent thresholds regardless of the equipment, this paper presents the RETSPLs initially obtained following ISO 389-9:2009 and suggested correction to account for the elevated HLs of the originally recruited populations. Two additional independent studies demonstrate the validity of these corrected thresholds.
... Given the possibility of using supra-aural, insert, or circumaural earphones to obtain air-conduction hearing thresholds at 250 to 8000 Hz, we must compare them and verify the users' satisfaction with them. We commonly find studies reporting the difference in hearing thresholds obtained with supra-aural and insert earphones in different populations (5,6,(8)(9)(10)(11)(12) , whereas comparisons with circumaural earphones are still scarce (6,17) . ...
Article
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Purpose: To compare the air-conduction hearing thresholds obtained with different acoustic transducers and verify the users' preferences regarding them. Methods: This is a cross-sectional, analytical, observational study with 26 participants aged 18 to 30 years, with normal hearing and no history of exposure to high sound pressure levels or complaints of tinnitus at the time of the assessment. We surveyed their medical history and performed meatoscopy, pure-tone threshold audiometry, speech audiometry, and acoustic immittance. The auditory thresholds were surveyed twice, each time with a different type of acoustic transducer: insert (E-A-RTONE) and circumaural earphones (HDA200). The assessments were performed in a random order, with 5-minute intervals. In the end, we asked the participants which earphones they found more comfortable in the tests. The data were submitted to nonparametric statistical analysis. Results: Assessing the medians in the auditory threshold survey, the circumaural earphones obtained better results at 250, 500, 2000, and 6000 Hz, while the insert earphones were better at 3000 and 4000 Hz; there were no statistical differences at 1000 and 8000 Hz. The circumaural was elected the most comfortable earphone. Conclusion: The circumaural earphones had better auditory thresholds at 250, 500, 2000, and 6000 Hz than the insert earphones and were reported by the patients as the most comfortable type of transducer.
... However, other unconventional measures have been explored and found to be promising surrogates for audiometric testing. 39 Potential bias could have been introduced in the regression models by using the fit test to assess both hearing loss and PAR. In addition, in order to expedite data collection, the software was set to present pure tones to both ears simultaneously, rather than to one ear at a time. ...
Article
Objective This study investigated risk factors for poor earplug fit, with a focus on the association between hearing loss and personal attenuation ratings (PARs). Methods Earplug fit was assessed by obtaining PARs using a real ear at attenuation threshold (REAT) system. Hearing loss was assessed using the unoccluded hearing thresholds measured during the REAT testing and the results of a speech-in-noise test. Potential predictors of PARs were modelled using both simple and multiple linear regression. Hearing loss was the primary predictor of interest. Results Data were collected from 200 workers at ten above-ground mining sites in the Midwestern USA. Workers reported wearing their hearing protection on average 73.9% of the time in a high noise environment (mean 8-hour time-weighted average noise exposure 85.5 dBA, range 65–103 dBA). One-quarter (26.7%) of workers were found to have a hearing loss (hearing threshold ≥25 dB across 1–4 kHz), and 42% reported symptoms of tinnitus. Workers with a hearing loss had a significantly lower PAR than those without a hearing loss (β=−5.1, SE=1.7). Conclusions The results of the adjusted regression models suggest that workers with hearing loss achieved significantly lower PARs than those without hearing loss. This association between hearing loss and hearing protection devices (HPD) fit brings into focus the potential benefit of fit checks to be included in hearing conservation programmes. Workers found to have hearing loss should be prioritised for fit testing, as their hearing impairment may be associated with poor HPD fit.
... The results show that 98% of hearing thresholds (8e16 kHz) were within 10 dB on retest. Flamme et al. (2015) compared the Sennheisser HDA 200 circumaural and the TDH39 supra-aural earphone. Test-retest reliability with the circum-aural earphone was reported to be at least as good, and possibly better, than the supra-aural earphone. ...
Article
Extended high frequencies (EHF), above 8 kHz, represent a region of the human hearing spectrum that is generally ignored by clinicians and researchers alike. This article is a compilation of contributions that, together, make the case for an essential role of EHF in both normal hearing and auditory dysfunction. We start with the fundamentals of biological and acoustic determinism - humans have EHF hearing for a purpose, for example, the detection of prey, predators, and mates. EHF hearing may also provide a boost to speech perception in challenging conditions and its loss, conversely, might help explain difficulty with the same task. However, it could be that EHF are a marker for damage in the conventional frequency region that is more related to speech perception difficulties. Measurement of EHF hearing in concert with otoacoustic emissions could provide an early warning of age-related hearing loss. In early life, when EHF hearing sensitivity is optimal, we can use it for enhanced phonetic identification during language learning, but we are also susceptible to diseases that can prematurely damage it. EHF audiometry techniques and standardization are reviewed, providing evidence that they are reliable to measure and provide important information for early detection, monitoring and possible prevention of hearing loss in populations at-risk. To better understand the full contribution of EHF to human hearing, clinicians and researchers can contribute by including its measurement, along with measures of speech in noise and self-report of hearing difficulties and tinnitus in clinical evaluations and studies.
... Schmuziger et al. (2004) reported good test-retest reliability of audiometric thresholds with the HDA 200 earphone from 0.5 to 12.5 kHz, with slightly poorer reliability from 14.0 to 16.0 kHz. Flamme et al. (2015) compared the test-retest reliability of HDA 200 earphones with that of supra-aural TDH-39P earphones and found lower testretest variability with the HDA 200 especially in the higher frequencies (9.0-16.0 kHz). ...
Article
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Objective: The Sennheiser HDA 200 earphone, a standard circumaural earphone used in audiometry for many years, is out of production and is replaced by the RadioEar DD450. The Sennheiser HD 280 Pro earphone is a consumer product that has characteristics that may be suitable for audiometry and may be a low-cost alternative to the DD450. The DD450 and HD 280 Pro earphones were compared with the HDA 200 for use in audiometry. Design: RadioEar DD450 and Sennheiser HD 280 Pro earphones were evaluated for reference equivalent threshold sound pressure levels (RETSPLs), ambient-noise attenuation, and occlusion effects. Audiometric thresholds measured on a group of normal-hearing adults were used to determine RETSPLs. Ambient-noise attenuation was determined by measuring the sound pressure in the ear canal produced by a broadband signal from a loudspeaker with and without occlusion by the earphone. Acoustic occlusion effects were determined by measuring the ear-canal sound pressure produced by a bone-conducted source with and without occlusion by the earphone. The results were compared with measurements obtained from the HDA 200 earphone. Results: Audiometric thresholds obtained using the DD450 earphone did not differ from those obtained with the HDA 200 earphones, indicating that the HDA 200 RETSPLs provided in the audiometer standards (ANSI S3.6-2010; ISO 389-8-2004) are transferable to the DD450. New RETSPLs for the HD 280 Pro earphone were determined from the threshold measurements. Ambient-noise attenuation provided by the DD450 was equivalent to the attenuation provided by the HDA 200. The HD 280 Pro provided less ambient-noise attenuation than the other circumaural earphones, but more than the supra-aural earphones commonly used in audiometry. The DD450 produced an occlusion effect 5 dB larger than that of the HDA 200 at 0.25 and 0.5 kHz; both earphones produced negligible occlusion effects at higher frequencies. The HD 280 Pro produced larger occlusion effects in the low frequencies than the other two earphones, with negligible occlusion effects at 1.0 kHz and above. Conclusions: The HDA 200 RETSPLs are transferable to the DD450. Ambient-noise attenuation and occlusion effects are similar for these two earphones. RETSPLs for the HD 280 Pro are provided. The HD 280 Pro has less ambient-noise attenuation and larger occlusion effects than the DD450 but is a viable low-cost alternative.
... However, there is no evidence in the literature, on the contrary, only marginal differences were found [32]. Similarly, the circumaural transducers of the second study have a better external noise attenuation than the supraaural transducers of the first study and measurement results are more reliable [33]. Another limitation may be the relatively small number of 36 participants, which, however, is of less importance in longitudinal than in cross-sectional studies. ...
Article
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Background Military musicians are working in a noisy environment with high sound exposure levels above the international standards. Aim of the current study is to find out, whether they develop the expected hearing impairments. Adherence to the regulations for prevention in musicians is more difficult than in other occupational fields. Methods In an interval of 13.3 years, 36 out of 58 male military musicians of a German army music corps were subjected twice to an audiometric audit. There were no exclusion criteria apart from acute ENT infections (three musicians). These results were compared with one another and evaluated by means of statistical methods for relationships with several factors. Results At frequencies below 3 kHz, the follow-up audiograms were up to 5 dB better than the preliminary examination. From 4 kHz up to 8 kHz the preliminary investigations showed less hearing impairment. Averaging all frequencies the improvement of hearing ability was around 1 dB. Above 1 kHz the average hearing of the right ear was up to 7 dB better than that of the left ear. Age-induced hearing loss was 3 to 8 dB lower than predicted by ISO standards over the entire frequency range. The side of the ear (right/left) and the frequency (3, 4, and 6 kHz) were significant (p < 0.05) in hearing loss, whereas the influence of the instrument and the acoustic traumata were not. Conclusion Despite the high noise levels, the average hearing ability of the 36 military musicians during the investigation period only slightly deteriorated in the noise-sensitive frequencies (3, 5 and 6 kHz). Music may be less harmful than industrial noise, or the long-term auditory training of the musicians leads to a delayed presbycusis.
... The difference between results of the clinical audiometry (gold standard) and the thresholds measured with the 2-tone test, also expressed in decibels hearing level, are shown in Figure 4 . The clinical audiometry results were measured with headphones and presented along the [Flamme et al., 2015]. The correlation coefficients were 0.91, 0.76, and 0.87, respectively. ...
Article
This study investigated the potential and limitations of a self-fit hearing aid. This can be used in the "developing" world or in countries with large distances between the hearing-impaired subjects and the professional. It contains an on-board tone generator for in situ user-controlled, automated audiometry, and other tests for hearing aid fitting. Twenty subjects with mild hearing losses were involved. In situ audiometry showed a test-retest reliability (SD <3.7 dB) that compared well with the precision of diagnostic audiometry using headphones. There was good correspondence (SD <5.2 dB) with traditional pure-tone audiometry. In situ loudness scaling yielded important information about suprathreshold perception, which will have an added value for the selection of compression and the selection of maximum power output to be allowed in hearing aids.
... Swanepoel et al (2010) also tested all listeners on the same day using both manual and automated audiometry (only automated reported in Table 4), using insert earphones under circumaural ear cups. Flamme et al (2015) tested listeners on multiple sessions (all sessions combined in the reported data) using a TDH-39 and an HDA200 (only HDA200 with pure tones included in the table). Although the Flamme et al (2015) data were not obtained all during a single session, the data are included to provide a comparison with circumaural earphones test-retest. ...
... Flamme et al (2015) tested listeners on multiple sessions (all sessions combined in the reported data) using a TDH-39 and an HDA200 (only HDA200 with pure tones included in the table). Although the Flamme et al (2015) data were not obtained all during a single session, the data are included to provide a comparison with circumaural earphones test-retest. The key, however, is that the outcomes for the current study were achieved in an industrial setting, outside of a sound booth and with untrained operators. ...
... ER-3A (Swanepoel et al, 2010; N ¼ 60) HDA200 (Flamme et al, 2015; N ¼ 49) Note: All except Flamme et al. (2015) did two consecutive measurements during a single session. Flamme data are included to provide a comparison with circumaural earphones. ...
Article
Objective: To assess the test-retest variability of hearing thresholds obtained with an innovative, mobile wireless automated hearing-test system (WAHTS) with enhanced sound attenuation to test industrial workers at a worksite as compared to standardised automated hearing thresholds obtained in a mobile trailer sound booth. Design: A within-subject repeated-measures design was used to compare air-conducted threshold tests (500-8000 Hz) measured with the WAHTS in six workplace locations, and a third test using computer-controlled audiometry obtained in a mobile trailer sound booth. Ambient noise levels were measured in all test environments. Study sample: Twenty workers served as listeners and 20 workers served as operators. Results: On average, the WAHTS resulted in equivalent thresholds as the mobile trailer audiometry at 1000, 2000, 3000 and 8000 Hz and thresholds were within ±5 dB at 500, 4000 and 6000 Hz. Conclusions: Comparable performance may be obtained with the WAHTS in occupational audiometry and valid thresholds may be obtained in diverse test locations without the use of sound-attenuating enclosures.
... Despite a large number of general books and papers published over the past 50 years advocating the use of narrow-band complex sounds for hearing testing, our literature review found only a few studies in which the thresholds of hearing for narrow-band complex sounds and pure tones were directly compared [10,16,18,19,36,44,51,52,53]. All of the studies cited above provide threshold differences of Type C (in Figure 1). ...
... These small differences support the notion that hearing thresholds for pure tones and 1/3-octave band noises in the range up to 4000 Hz are, for all practical purposes, equal. This in-practice equality may also be extended to hearing thresholds measured with noise bands corresponding to ERBs [18] and to Zwicker's critical bands [16] and in fact to any noise bands with bandwidth narrower than critical bands. It is noteworthy that even the differences between pure tone and 2/3-octave band noise thresholds reported by Simon & Northern [52] andat some frequencies -by Garstecki & Bode [19] do not exceed ±3 dB. ...
... The difference curve in Figure 3 can only be drawn up to 4000 Hz. The reason for this is that for frequencies above 4000 Hz there are not enough data points to determine the extent of the difference between both thresholds (PT and NB), although the data points provided by Fastl & Baumgartner [16], Fastl [15] and Flamme at al. [18] do speak to the close similarity of both thresholds. The threshold differences at 6000 Hz and 8000 Hz reported by Mitrinowicz-Modrzejewska & Łętowski [36] are similar (although smaller) to the differences observed in studies conducted with hearing impaired listeners with sloping high frequency hearing loss [44,52,53]. ...
Article
Full-text available
Narrow-band noises are frequently used as test signals in audio system evaluation, psychoacous-tics, noise control, and technical listening skills development programs. In perceptual audio assessment and technical listening skills development studies it is crucial that the hearing level thresholds and equal loudness contours for such signals are known in order to ensure proper calibration of the test signals. However, the data regarding human sensitivity to narrow-band noises that are available in the psychoacoustic literature are very limited. Except for threshold values for one-third octave noises presented in a diffuse sound field no other data have been normalized, and even for the threshold data there is still some disagreement in the literature. This paper presents a critical analysis of the existing literature on the human sensitivity to narrow-band signals with a focus on hearing thresholds for one-third octave noises under both loudspeaker and earphone listening conditions. On the basis of this analysis recommendations are made for the perceptual calibration of narrow-band noise signals and their use in auditory training and audio assessment studies.
Article
Use of the audiogram as the gold standard index of hearing ability amplifies the consequences of error in threshold measurement. A Markov chain model of the audiometric procedure revealed a three-step pattern in the stimuli presented each trial. Monte Carlo simulations were used to generate threshold estimates for a simple listener model. Thresholds sorted by trial had a mean bias consistent with model predictions. An alternate scoring method is proposed that uses equal sampling of Markov states. The resulting threshold targets a specific probability of detection and has no systematic bias as a function of trial.