WO2007072280A1

WO2007072280A1 - A device for and a method of processing audio data

Info

Publication number: WO2007072280A1
Application number: PCT/IB2006/054701
Authority: WO
Inventors: Julien L. Bergere
Original assignee: Koninklijke Philips Electronics NV
Current assignee: Koninklijke Philips NV
Priority date: 2005-12-22
Filing date: 2006-12-08
Publication date: 2007-06-28
Anticipated expiration: 2008-06-22

Abstract

A device (100) for processing audio data, the device (100) comprising an amplitude detection unit (101) adapted to detect an amplitude of the audio data, and a correction unit (102) for selectively attenuating the amplitude of the audio data in a mid-to- high audible frequency range in case of detecting that the detected amplitude exceeds a predetermined threshold value.

Description

A device for and a method of processing audio data

FIELD OF THE INVENTION

The invention relates to a device for processing audio data. The invention further relates to a method of processing audio data. Moreover, the invention relates to a program element. Further, the invention relates to a computer-readable medium.

BACKGROUND OF THE INVENTION

Audio playback devices become more and more important. Particularly, an increasing number of users buy portable audio players and other entertainment equipment. WO 2005/004114 discloses a sound reproduction system comprising a digital audio signal input, a digital audio signal processor, and a digital audio signal output, wherein the digital signal processor comprises a high pass filter, a compression amplifier for compression and amplification of a signal within a signal amplitude range, and a clipper for clipping the signal above a clipping level. The parameters of the various elements such as cut-off frequency, order of the pass filter, gain, etc. are dependent on a measured noise level. However, there are circumstances under which the audio playback quality of the system of WO 2005/004114 is not sufficient.

OBJECT AND SUMMARY OF THE INVENTION It is an object of the invention to enable improved audio playback.

In order to achieve the object defined above, a device for processing audio data, a method of processing audio data, a program element and a computer-readable medium according to the independent claims are provided.

According to an exemplary embodiment of the invention, a device for processing audio data is provided, the device comprising an amplitude detection unit adapted to detect an amplitude of the audio data, and a correction unit for selectively attenuating the amplitude of the audio data in a mid-to-high audible frequency range in case of detecting that the detected amplitude exceeds a predetermined threshold value. According to another exemplary embodiment of the invention, a method of processing audio data is provided, the method comprising detecting an amplitude of the audio data, and selectively attenuating the amplitude of the audio data in a mid-to-high audible frequency range in case of detecting that the detected amplitude exceeds a predetermined threshold value.

According to still another exemplary embodiment of the invention, a program element is provided, which, when being executed by a processor, is adapted to control or carry out a method of processing audio data having the above mentioned features.

According to yet another exemplary embodiment of the invention, a computer- readable medium is provided, in which a computer program is stored which, when being executed by a processor, is adapted to control or carry out a method of processing audio data having the above mentioned features.

The audio processing according to embodiments of the invention can be realized by a computer program, that is by software, or by using one or more special electronic optimization circuits, that is in hardware, or in hybrid form, that is by means of software components and hardware components.

According to an exemplary embodiment of the invention, it is possible to selectively damp particular contributions of audio content which exceed a loudness threshold, wherein the attenuation may be restricted to one or more special frequency intervals. Especially the mid-to-high audible frequency range is believed to be particularly prone to the generation of audio output, which frequency range a human listener in many cases perceives to be non-harmonic or to cause pain. By selectively damping audio contributions in a corresponding frequency range of, for instance 1 kHz to 20 kHz, in which the hearing sensitivity and the danger of a subjective feeling of pain is high, the subjective or perceived audio quality may be significantly improved.

The term "mid-to-high" audible frequency range may particularly cover a frequency range above the bass regime, but below the treble regime. Particularly, the term mid-to-high audible frequency range may cover frequencies in the domain between 1 kHz and 20 kHz. Dividing the audible frequency spectrum in bass frequency, mid frequency and treble frequency sub-portions, the bass regime may remain undamped, the mid frequency regime may be damped, and of the treble regime, only a low- frequency portion may be damped, wherein a high-frequency portion of the treble regime may remain undamped. The term "mid-to-high" audible frequency range may particularly be understood as a synonym for the term "high-midrange" frequencies, that is to say an audible frequency range between medium frequencies and high treble frequencies.

According to an exemplary embodiment, a harshness reduction for a sound system may be provided. In order to correct for the fact that sound and music reproduction systems sound harsh when playing loud, an attenuation of frequencies, for instance, in the 1 kHz to 20 kHz range (preferably in the 2 kHz to 8 kHz range) may be implemented at any desired position in an audio reproduction system. Embodiments of the invention may be active or passive implementations of the selective attenuation feature.

When addressing the problem of ensuring that music is correctly reproduced when played loud, main attention usually goes to making sure that the area of largest THD (total harmonic distortion) is contained. This cause is often an electronic hard clipping of the signal at low frequencies (in an amplifier or in a pre-amp lifter), or mechanical clipping of the loudspeaker at low frequencies (where the excursion of the loudspeaker diaphragm is the highest). However, though certainly audible, distortion in the bass is not always the main reason of auditory discomfort at loud listening levels. It has been recognized that harsh sound is often what listeners complain about. The reason of this phenomenon is not clear, and seems to be linked to the quality of the sound reproduction system (high-quality hi-fi systems are less affected), as well as to the properties of the auditory system (the pain threshold expressed in dB SPL is lower for high frequencies, for instance). In view of the foregoing, according to an exemplary embodiment, a sound reproduction system for reproducing sound signals is provided, comprising correction elements designed to correct the loudness of the sound signal by reducing the output level of the sound signals in the mid-high frequency area.

The reduction of output at mid- high frequencies can be incremental and may be increased as the loudness reproduced by the system is increased. It may also be dynamic, changing with the music energy and/or spectral component.

Exemplary embodiments of the invention may have the advantage that a sound system may be prevented from sounding harsh when played loud. Furthermore, the system may prevent hearing damage thanks to a subjectively well-balanced frequency spectrum at all listening levels. Furthermore, corrections for harsh sounding systems may be performed even at moderate levels (earphones), and it may be possible to correct even more audible artefacts at high loudness.

Exemplary applications of embodiments of the invention are all fields in which an improvement of the sound experience by reducing discomfort or danger caused at high listening volume (healthcare aspect), is desired, and apply to all music or speech reproducing systems. Particularly, a portable audio device used with headphones (like an MP3 player or a mobile phone), headphones and earphones, sound and music reproduction systems equipped with loudspeakers, loudspeakers, night club sound systems, and music stage sound systems are exemplary fields of application of embodiments of the invention.

Thus, an audio device or sound system may be provided with harshness reduction for improving the perceived quality of the sound by sound level dependent attenuation of frequencies in the mid range frequency band.

It is believed that little is known about why a sound is unpleasant to a human listener. It can be stated that in some cases unpleasantness can be linked to a too large SPL ("sound pressure level"), approaching the threshold of pain. This pain threshold may be frequency dependent and may be minimum at frequencies where the ear is most sensitive, as illustrated by the Fletcher-Mundson curves.

With two different audio systems presenting the same high overall measured loudness of a music piece, a high quality system will be enjoyable to listen for hours, and a low quality system will become annoying and give a headache to a human listener. It is believed that this is partly due to the fact that the low quality systems have sharp resonances in their frequency response, meaning that though the average level of exposure is spread across the frequency spectrum is the same, there are some precise frequencies where the ear is subject to high levels, approaching the pain threshold.

Even audio Io gists lack precise or converging information allowing making a direct link between the frequency of a loud and annoying auditory signal, and hearing impairment resulting of exposures to this auditory signal. What is sure is that exposure to loud sounds can impair hearing, wherein different human listeners may have a different vulnerability to it.

Discomfort being the first stage before reaching pain, it could be postulated that reducing the subject's exposure to loud auditory signals described as "unpleasant" (though not actually reaching the pain threshold) will reduce the chance for the subjects to suffer from hearing impairment in the future. A European law based on the EN 50332-1 and EN 50332-2 standards limits the maximum SPL produced by portable audio players equipped with headphones to 100 dBA SPL. However, it is believed that this measure is not sufficient to prevent hearing impairment, as a maximum of 15 minutes daily exposure to 100 dBA is usually considered as the maximum to avoid getting hearing impairment. Reducing the harshness of sound in music playback at high loudness is beneficial to the user's auditory comfort, and very likely to the performance of her or his ears even in case of regular prolonged use. Thus, from the comfort and from the healthcare point of view, such a frequency specific loudness reduction might be advantageous. Exemplary fields of application of embodiments of the invention are earphones. Earphones which sound well-balanced when played at reasonable loudness (good relative loudness of all parts of the reproduced spectrum) may sound quite harsh when played very loud (situation which naturally occurs when playing back sound in a noisy environment like in a car, for instance). An acoustic engineer is faced with designing earphones that sound best at low or at high loudness. In practice, users need both, and especially should not be subject to too harsh sound at high listening levels (tiring or even painful in some cases).

Similar considerations apply to loudspeakers, especially small active speaker systems or so-called "boomboxes" that are often played loud.

In the light of the foregoing, it may be advantageous to remedy to harshness (particularly of sound or music reproduction systems) at high loudness by reducing the output level of mid-high frequencies at the mentioned high loudness. The reduction of output at mid-high frequencies can be incremental, it being increased as the loudness reproduced by the system is increased. It can be dynamic, changing with the music energy and spectral component. Embodiments of the invention cover all possibilities of reducing the mid- high frequency content of the sound produced by an electro-acoustic device aimed at reproducing music, or more generally sound, in particular when playing loud. "Mid-high" frequencies can be particularly considered to be 1 kHz to 20 kHz.

The attenuation of mid-high frequencies can be down in an analog manner or in a digital manner.

The attenuation may be, for the sake of simplicity, performed in a preamplifier for systems having an amplifier and a pre-amplifϊer, but can also be performed in the main amplifier, or at a system level in an architecture involving, for instance, a feedback loop including the loudspeaker, the amplifier, the pre-amplifϊer, and any sound features (like an equalizer, a bass boost, a virtualizer). A system built around the loudspeaker itself is also covered by embodiments of the invention.

The reduction of the audio amplitude in a frequency-dependent manner according to embodiments of the invention may be more pronounced in the area of the audible spectrum where the ear is the most sensitive and where the pain threshold is the lowest, which is the 3 kHz to 5 kHz region.

It can be applied as a static correction (for example in a manner of an "on/off feature activating a fixed equalization curve, which makes the sound less harsh if the system is playing loud and the feature is turned "on"), or as a dynamic one (mid-high frequency attenuation appears and increases as volume control is put to a louder position or as the complete amplified signal goes beyond a certain threshold, or as a part of the signal's spectrum reaches a certain relative value compared to the rest of the spectrum. The dynamic implementations can be "on/off or blind (that is always "on", but has only effect when needed) features.

Exemplary fields of application of the invention are headphones and earphones with loudness protection, an algorithm for earphones for mobile applications, DSP chips for audio applications like symphony, headphones and speakers amplifiers, personal infotainment and mobile phones, earphones with integrated electronics, main mobile phones, portable audio devices and headphones.

The measures taken according to exemplary embodiments of the invention may yield the result that sound, even when played back at high volume, does not sound aggressive. Harshness may be compensated when the intensity level of the audio content is decreased in the mid- frequency range, depending on the loudness within an audio track. Next, further exemplary embodiments of the invention will be described. In the following, exemplary embodiments of the device for processing audio data will be described. However, these embodiments also apply for the method of processing audio data, for the program element and for the computer-readable medium.

The amplitude detection unit may be adapted to detect the amplitude of the audio data in a frequency-selective manner. In other words, a frequency selective detection may be implemented to refine the basis for the decision to which extent in which frequency range an attenuation should be performed.

The amplitude detection unit may be adapted to detect the amplitude of the audio data in a "static" manner. For a low cost application, it may be possible to adjust the attenuation parameters (range of attenuated frequencies, extent or amount of attenuation, etc.) once without any options to modify these parameters. This may have the advantage that the attenuation may be adjusted constantly, for instance based on medical knowledge, so as to provide a medical security feature in an audio playback product that is in accordance with anatomic properties of an "average" human user. Thus, a human listener may be securely prevented from hearing impairment when using such an audio playback product.

However, the amplitude detection unit may be adapted to detect the amplitude of the audio data in a "dynamic" manner, particularly based on current parameters of the audio content to be reproduced. Such a dynamic configuration may provide a high degree of flexibility, since the parameters of attenuation as mentioned beforehand may be adjusted in a time-dependent manner and/or in an audio content-dependent manner in dependence of various parameters, for instance changing with music energy and/or spectral content. Furthermore, it is possible to take into account for the determination of attenuation parameters like the characteristics of a human listener, like gender, size, personal preferences, or the like. A user may input such parameters so that the system may then calculate attenuation characteristics in accordance with the input parameter(s).

The correction unit may be adapted for selectively attenuating the amplitude of the audio data in a frequency-dependent manner within the mid-to-high audible frequency range. In other words, the attenuation in the mid-to-high audible frequency range does not necessarily has to be constant, but may take into account modifications within this range, for instance the fact that the human ear is very sensitive in the 3 kHz to 5 kHz range so that this sub-range of the mid-to-high audible frequency range may be attenuated in a stronger manner as compared to other frequency ranges within the mid-to-high audible frequency range. Particularly, the correction unit may be adapted for incrementally (particularly stepwise) attenuating the amplitude of the audio data. This may allow for a refined correction which may make sure that a human listener perceives the processed audio data stream to be of proper quality and to be non-disturbing.

The correction unit may be adapted for selectively attenuating the amplitude of the audio data within a frequency range between essentially 1 kHz and essentially 20 kHz, particularly between essentially 2 kHz and essentially 8 kHz. These frequency ranges are those in which the human ear is usually prone to a pain reception as a result of audio playback of a very high intensity.

More particularly, the correction unit may further be adapted for selectively attenuating the amplitude of the audio data within a frequency range between essentially 3 kHz and essentially 5 kHz. This is a range that is considered to be the audio regime in which the sensitivity of the human ear is a maximum so that this range is particularly prone to a subjective pain perception. The correction unit may further be adapted for selectively attenuating the amplitude of the audio data so that the attenuated amplitude does no longer exceed a predetermined loudness level. Such a loudness level may be selected to be in accordance with legal frame conditions, or with frame conditions derived from experiments performed with human listeners indicating that exceeding a particular loudness level may cause pain for a significant percentage of human listeners.

Beyond this, the device may comprise a pre-amplifier and a main amplifier, wherein the amplitude detection unit and/or the correction unit may be located within the preamplifier positioned in an audio processing path preceding the main amplifier. Positioning the detection unit and the correction unit at such a position may be a very simple solution.

However, alternatively, the amplitude detection unit and/or the correction unit may be located within the main amplifier positioned in an audio processing path succeeding the pre-amplifier.

Further alternatives to these configurations are possible. For instance, the device may comprise an audio reproduction unit, and the amplitude detection unit and/or the correction unit may be located within the audio reproduction unit.

The device may be realized as an earphone, a loudspeaker, a night club sound system, a music stage sound system, a GSM device, headphones, a gaming device, a laptop, a portable audio player, a DVD player, a CD player, a harddisk-based media player, an internet radio device, a public entertainment device, an MP3 player, a hi-fi system, a vehicle entertainment device, a car entertainment device, a portable video player, a mobile phone, a medical communication system, a body-worn device, and a hearing aid device.

However, although the system according to embodiments of the invention primarily intends to improve the playback of sound or audio data, it is also possible to apply the system for a combination of audio data and visual data. For instance, an embodiment of the invention may be implemented in audiovisual applications like a video player in which a loudspeaker is used, or a home cinema system.

The aspects defined above and further aspects of the invention are apparent from the examples of embodiment to be described hereinafter and are explained with reference to these examples of embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail hereinafter with reference to examples of embodiment but to which the invention is not limited.

Fig. 1 shows an audio data processing system according to an exemplary embodiment of the invention. Fig. 2 shows an audio data processing system according to another exemplary embodiment of the invention.

DESCRIPTION OF EMBODIMENTS

The illustration in the drawing is schematically. In the following, referring to Fig. 1, an audio processing system 100 will be described.

The audio processing device 100 comprises an amplitude detection unit 101 adapted to detect an amplitude of audio data emitted by a source of digital audio signals 105 after having passed a sound feature unit 106 including components like an equalizer, a surround function, a dynamic bass boost, etc.

After having passed the sound feature unit 106, the processed audio stream is passed through a user controlled volume control unit 107. Thus, a user of the system 100 may adjust a desired loudness by adjusting the volume control unit 107.

Afterwards, the processed stream 120 is guided through a harshness reduction unit 108 which may be switched "on" or "off according to the embodiment of Fig. 1.

Fig. 1 further shows a more detailed view of the internal constitution of the harshness reduction unit 108. The audio data 120 provided at an input of the harshness reduction unit 108 leaves the harshness reduction unit 108 as audio data 121 that is supplied to a digital-to-analog converter (DAC) 109. From there, the data is supplied to an amplifier 103 with fixed gain, and may be passed to earphones 104 for reproduction, that is for emission of acoustic waves.

In the following, the internal constitution of the harshness reduction unit 108 will be described in more detail.

When the audio data 120 enters the harshness reduction unit 108, the audio data 120 is supplied to an input of the amplitude detection unit 101 that is adapted to detect an amplitude of the audio data 120. Such detection may include a loudness-detection (for instance using a dBA filter), with the integration time constant.

Furthermore, the harshness reduction unit 108 comprises a correction unit 102 for selectively attenuating the amplitude of the audio data 120 in a mid-to-high audible frequency range in case of detecting, by the amplitude detection unit 101, that the amplitude exceeds the predetermined threshold value. The correction unit 102 is realized as a notch filter having a frequency of 4 kHz, a Q-value of two (2) and a gain that is a function of an input signal L dB A provided by the amplitude detection unit 101. As can be taken from Fig. 1, an on/off switch unit 112 controls a first switch

110 and a second switch 111 to be opened or closed, corresponding to an "on" and to an "off state of the amplitude detection and frequency selective attenuation.

In an operation state shown in Fig. 1, the first switch 110 is closed and the second switch 111 is open so that the audio data 120 is passed through the correction unit 102, wherein the functionality of the correction unit 102 is controlled by the output signal of the amplitude detection unit 101. Thus, a mid-to-high frequency component of the audio data

120 is selectively damped. After having passed an adding unit 113, the processed audio data

121 leaves the harshness reduction unit 108 and is supplied to the DAC 109.

However, in another operation state that is not shown in the figures, the on/off control unit 112 (which may be user-controlled) may bring the first switch 110 in an open state and may simultaneously bring the second switch 111 in a closed state. Then, the correction unit 102 is bypassed by the audio data 120 so that, after having passed the adding unit 113, the audio data 120 is essentially identical to the audio data 121, that is to say no attenuation function is realized. The amplitude detection unit 102 may detect the amplitude of the audio data

120 in a frequency- selective manner. The correction unit 102 selectively attenuates the amplitude of the audio data 120 so that attenuated amplitude falls below a predetermined loudness level as defined by the loudness detection unit 101.

The function f giving the gain of the shelf filter 102 may be defined by playing a "100 dB test" test signal as the source signal, all other sound features being in the conditions that maximize the measured dBA level. For this L dBA max value, a suitable gain for the notch filter 102 is defined by listening (sound should be less harsh, but not too dull), for instance -12 dB.

If L dBA χ L dBA max, f(L_dBA_max) = -12 dB. Listening to different music tracks and deciding when the system's sound starts to be harsh may define a value L dBA min. Below L dBA min, the notch filter 102 has unity gain (0 dB).

If L dBA α L dBA min, f(L_dBA_min) = 0 dB. The gain of the notch filter 102 for values of L dBA between L dBA min and L dBA max are linearly extrapolated (on the dB scale).

In the following, referring to Fig. 2, an audio processing system 200 according to another exemplary embodiment of the invention will be described. The audio data processing unit 200 comprises a first section 210 representing a player (volume control at maximum), and comprises a second portion 220 representing headphones (with a volume control).

The player 210 has an amplifier 201 and an adjustable resistor 202 having resistor values between 0 and 20 Ohms. The amplifier 201 has a ground connection 209. An input of the headphone portion 220 is coupled to an output of the player portion 210 and comprises a resistor 203 (potentiometer) with an adjustable value of the resistance, between a minimum and a maximum value. Before passing a processed audio stream to a loudspeaker 205 having a resistance of 16 Ohms and having a ground connection 209, the data traverses a notch filter 204 at 3.5 kHz and a Q-factor of (essentially) 3. The notch filter 204 comprises a circuit of a capacitance 206, a resistor 207 and an inductance 208 which are connected parallel to one another. The notch filter 204 has the function of a correction unit for selectively attenuating the amplitude of the audio data in a mid-to-high audible frequency range in case of detecting that the amplitude exceeds a predetermined threshold value. The embodiment of Fig. 2 relates to headphones with volume control. It may be assumed that the output amplifier 201 of the player portion 210 has (essentially) 0 Ohm output impedance.

- When the slide resistor 203 of 500 Ohms is in a "min" position, the notch filter 204 provides at 3.5 kHz an attenuation of 20xlog (564/516) = 0.77 dB compared to the level outside the frequency range of the notch filter 204. At low volume, the headphone loudspeaker 205 is supplied with a signal having nearly the spectrum produced by the player 210.

- When the slide resistor 203 is in a "max" position, the notch filter 204 provides at 3.5 kHz an attenuation of 20xlog (64/16) = 12 dB compared to the level outside the range of the notch filter 204. At maximum volume, the headphone loudspeaker 205 is supplied with a signal which results from applying a 12 dB notch filter 204 at 3.5 kHz to a player signal.

It can be seen that the value of 500 Ohms slide resistor 203 and 48 Ohms resistor 207 can be tuned so as to provide virtually any desired notch correction, at "min" volume and at "max" volume. With the system 200, it is therefore also possible to correct for headphones that sound harsh even at moderate loudness (because they suffer, for instance, of a peak at 4 kHz in their frequency response).

It should be noted that the term "comprising" does not exclude other elements or steps and the "a" or "an" does not exclude a plurality. Also elements described in association with different embodiments may be combined.

It should also be noted that reference signs in the claims shall not be construed as limiting the scope of the claims.

Claims

CLAIMS:

1. A device (100) for processing audio data, the device (100) comprising an amplitude detection unit (101) adapted to detect an amplitude of the audio data; a correction unit (102) for selectively attenuating the amplitude of the audio data in a mid-to-high audible frequency range in case of detecting that the detected amplitude exceeds a predetermined threshold value.

2. The device (100) according to claim 1, wherein the amplitude detection unit (101) is adapted to detect the amplitude of the audio data in a frequency- selective manner.

3. The device (100) according to claim 1, wherein the amplitude detection unit (101) is adapted to detect the amplitude of the audio data in a static manner.

4. The device (100) according to claim 1, wherein the amplitude detection unit (101) is adapted to detect the amplitude of the audio data in a dynamic manner.

5. The device (100) according to claim 1,| wherein the correction unit (102) is adapted for selectively attenuating the amplitude of the audio data in a frequency-dependent manner within the mid-to-high audible frequency range.

6. The device (100) according to claim 1, wherein the correction unit (102) is adapted for incrementally attenuating the amplitude of the audio data.

7. The device (100) according to claim 1, wherein the correction unit (102) is adapted for selectively attenuating the amplitude of the audio data within a frequency range between essentially 1 kHz and essentially 20 kHz.

8. The device (100) according to claim 1, wherein the correction unit (102) is adapted for selectively attenuating the amplitude of the audio data within a frequency range between essentially 2 kHz and essentially 8 kHz.

9. The device (100) according to claim 1, wherein the correction unit (102) is adapted for selectively attenuating the amplitude of the audio data within a frequency range between essentially 3 kHz and essentially 5 kHz.

10. The device (100) according to claim 1, wherein the correction unit (102) is adapted for selectively attenuating the amplitude of the audio data so that an attenuated amplitude falls below a predetermined loudness level.

11. The device (100) according to claim 1, comprising a pre-amp lifter and a main amplifier, wherein the amplitude detection unit (101) and/or the correction unit (102) is or are located within the pre-amp lifter positioned in an audio processing path before the main amplifier.

12. The device (100) according to claim 1, comprising a pre-amp lifter and a main amplifier, wherein the amplitude detection unit (101) and/or the correction unit (102) is or are located within the main amplifier positioned in an audio processing path after the pre-amplifier

13. The device (100) according to claim 1, comprising an audio reproduction unit (104), wherein the amplitude detection unit (101) and/or the correction unit (102) is or are located within the audio reproduction unit (104).

14. The device (100) according to claim 1, wherein the correction unit (102) is adapted for selectively attenuating the amplitude of the audio data exclusively in the mid-to-high audible frequency range in case of detecting that the detected amplitude exceeds the predetermined threshold value.

15. The device (100) according to claim 1, realized as at least one of the group consisting of an earphone, a loudspeaker, a night club sound system, a music stage sound system, a GSM device, headphones, a gaming device, a laptop, a portable audio player, a DVD player, a CD player, a harddisk-based media player, an internet radio device, a public entertainment device, an MP3 player, a hi-fi system, a vehicle entertainment device, a car entertainment device, a portable video player, a mobile phone, a medical communication system, a body-worn device, and a hearing aid device.

16. A method of processing audio data, the method comprising: detecting an amplitude of the audio data; selectively attenuating the amplitude of the audio data in a mid-to-high audible frequency range in case of detecting that the detected amplitude exceeds a predetermined threshold value.

17. A program element, which, when being executed by a processor (108), is adapted to control or carry out a method of processing audio data, the method comprising: detecting an amplitude of the audio data; selectively attenuating the amplitude of the audio data in a mid-to-high audible frequency range in case of detecting that the detected amplitude exceeds a predetermined threshold value.

18. A computer-readable medium, in which a computer program is stored which, when being executed by a processor (108), is adapted to control or carry out a method of processing audio data, the method comprising: detecting an amplitude of the audio data; selectively attenuating the amplitude of the audio data in a mid-to-high audible frequency range in case of detecting that the detected amplitude exceeds a predetermined threshold value.