Making Sense of Sound - Assignment Example

Soundscape Project 0. Introduction The idea of sounds in environment originated from Murray Schafer early in the year 1973. He started a project of the world soundscape known as the World Soundscape Project. The project was conducted by a group of people who made recordings for building a museum of sounds. In 1970, sound marks were collected by Peter Huse and Bruce Davis who went across Canada looking for disappearing and unique sounds. The field of study also known as the Acoustic Ecology that was started by Schafer, was discussed by professionals who came together in the year 1993. This project will discuss a soundscape within the environmental ecology. The project will identify a sound file and how it is generated. The report will also discuss in detail, the soundscape or the auditory scene within the acoustic ecology or the environment. The physical characteristics as well as the process and encoding of the sound of the auditory scene will be discussed in the report. Other aspects in the project reported in this paper, include the analysis of the perception as well as the interpretation of the sound’s perceptions. In this project, components such as audio recordings were used as methods of collecting the sound files made in the project. Sound files were easily made using computers with recording software. The audio would automatically set to play while the sound recording turned on at the same time the audio is playing in the computer. The computer automatically save the recorded file in the system. Other method of collecting the sound files is external recording, which involved recording sounds from environmental sources such as the water bodies. In the project, sounds from the birds and the water bodies were collected during the field study. 2.0. Physical Characteristics of the Sounds Spectrogram is a representation of spectrum or sounds. The representation of spectrum is visual. Spectra is analyzed using a spectrograph, which displays the analysis in three components namely; frequency, time and amplitude also known as the intensity (Mason, 2013). Time is normally displayed on the X-axis whereas the Y-axis represents the frequency and the variations of color or the greyscale darkness represents the amplitude of the sounds. During the soundscape or the field study, several sources of sound were observed and used to collect numerous sound files. Such sources as the flowing river and the birds among others were used to collect the sound files (Park, 2010). However, a numerous number of sound files were recorded but the project focused on the sound file collected from the flowing river (Park, 2010). The entire auditory environment had sounds that were determined by three components used in the representation of this sounds. The three components includes; frequency which is basically the number of revolutions completed by a wave in one second. The other component is the time also known as the period or the time taken to complete one revolution by a wave. Finally, the amplitude which is determined as the intensity of the wave. Amplitude is the maximum movement of a wave. In addition to this, the three components are used to represent the formation of a spectrogram. The frequency on the Y-axis and the X-axis showing the time while the intensity of the color is the size of the amplitude of the waves produced by the recorded sounds (Mason, 2013). The figure below is a spectrogram representing the spectrum using the three components time, frequency and amplitude. The sound waves recorded during the soundscape, is characterized by frequency, amplitude and time. The three components are essential in analyzing as well as presenting the information or the sound file recorded during the field study (Mason, 2013). Spectrograms and waveform are significant in labelling and segmenting a speech. The most clear visual cues are produced by the spectrograms to the limits between phonemes. However, accurate measurements of vowel formants are not provided by spectrograms. The frequency of spectrogram is poor and has a resolution of about 300 Hz (Park, 2010). Due to the poor frequency, there is a maximum range of the essential fault in the formant which might lead to errors in the measurements observed in the frequencies of formant. Consequently, the LPCs and the FFTs are used in order to get the appropriate measurements of the formant frequencies (Mason, 2013). 3.0. Processing and Encoding of Auditory Environment Encoding and processing of sound can be referred to as a process of representing the perception as well as the auditory sensation in nervous system. The ear canal provides entrance for the waves of sound. The ear canal is composed of a resonance, similar to an organ pipe. The resonance increases the sensitivity of human beings to frequencies of sound ranging from 1000 Hz to 6000 Hz. The sound waves causes a vibration on the ear drum since, it is a taut membrane. Three smallest bones in the body also known as the ossicles in general but are divided in three elements namely; incus, malleus and stapes. The three bones, carries the vibration from the ear drum through the middle ear. Conversion of the pressure variations takes place in a narrow tube, full of fluid and looped into a coil known as the cochlea. This can also be referred to as the process where the vibrations are transduced into electrical action in the auditory nerve’s neurons (Hiebert, 2014). Finally, the translation of the acoustic information into the brain language takes place in the auditory nerve. Pinna also known as the auricle is the component of the outer ear (Hiebert, 2014). The auricle is as well composed of the concha and the ear lobes which are visible parts of the outer ear. The function of this section of the ear is to collect the energy of the sound and pass it off to the ear drum. The pressure of the sound is boosted by resonances with frequencies ranging from 2 kHz to 5 kHz of sound waves (Hiebert, 2014). More accurate cues dealing with elevation from the origin of the sounds, are provided by pinna due to its symmetric structure. High frequency sounds are amplified form high elevation hence, providing a three dimension information by quality of its design in mechanics. The middle ear is significant in the process. It converts the variation of pressure in air to the fluid perturbations of the inner ear. In other terms, the middle ear is the mechanical transfer of the collected energy of sound between two media. The three small bones, the incus, the malleus and the stapes, are responsible for this conversion. The arrangement of the three bones is in such a way that they resonate at about 700 Hz to 800 Hz (Hiebert, 2014). In the process, the inner ear is prevented from extreme energy produced by the sound. In this region of the auditory scene, there are two muscles that can regulate the amount of energy entering the inner ear, by restraining the three bones or the ossicles. Thirdly, the inner ear also known as the cochlea, has two significances to the process (Hiebert, 2014). They analyze the frequency and amplifies the nonlinear or the elevated acoustics. In the cochlea, there are more than 32, 000 cells of hair. Travelling waves induced by the energy of sound are primarily amplified by the outer hair cells. On the other hand, the motion of the amplified waves is detected by the inner hair cells and impose excitement in the neurons of the auditory nerve (Hiebert, 2014). A high frequency range of the sound is encoded at the entrance of the sound energy in the cochlea. On the other hand, the low frequency sound is encoded at the end or the exit of the cochlea. The process ends in the auditory nerve. In this part of the ear, the information is translated into a language that the brain understands (Hiebert, 2014). After taking the sound energy, the auditory nerve acts the medium of information between the cortex and the ear. Processes the encoded information by translating it to the language of the brain. 4.0. Analysis of The Perceptions of Sound Auditory perception has different aspects that are manifested in the auditory scene. These aspects include; detection, pitch, masking, localization, loudness and quality of the sound. The mentioned aspects are discussed below in detail, and how they manifest the auditory scene in this soundscape project. Detection of sound waves is normally possible due to the vibrations of objects. In this project, the common device of detecting the sound waves is the ear (Schnupp, 2011). The small membrane in the ear, also known as the ear drum, vibrates due to the sound which also causes the vibration of the tiny hairs in the inner ear. As a result to the vibration of the hairs, electrical impulse is sent to the brain. The frequency of the sound produced in the project is kind of related to the pitch or the quality of the sound. Both the frequency and the pitch are focused on the quality of the sound produced in the project which has a range of low to high tone. If the existence as well as the presence of another sound affects the perception of sound. In this project, the auditory masking is observed where the voices and noises from the trees and the birds, affects the project on the collection of the main sound files (Schnupp, 2011). The presence of the sound from the birds and the trees interfered with the clearance and quality of the sound collected. Localization of sound is an auditory perception in which determining the origin or the location of the sound detected is within the ability of the listener. In the project, the listeners had the ability to identify the location of the sound as well as the origin of the sound they detected. This was significant to the project since they were getting closer to the identified origin for a clear observation. Finally, loudness can be described as the intensity range. If the source of sound is producing a loud sound, then the energy of the sound produced is high. In the project, some interfering sound were louder than the preliminary source. Basically the loudness of the sound is the range in the intensity or the amplitude difference (Schnupp, 2011). 5.0. Interpretation of the Auditory Scene This section deals with the auditory scene interpretation. The interpretation will involve the combination of the analyzed aspects above in the perception of the auditory scene. The above aspects deals with the type of sound that was produced by the project. The pitch, loudness, detection, masking and localization among others. All this aspects influenced the production of the sound since they determined the type of sound to be produced in the project. During the project, the detection was accurate, hence gave the members the chance to move closer to the source. Other aspects such as the pitch, masking and the loudness had an effect on the accuracy of the observation and recording. References Hiebert, E. (2014). The Helmholtz Legacy in Physiological Acoustics (Vol. 39). Springer. Mason, W. P. (2013). Physical acoustics. Elsevier Science. Park, T. H. (2010). Introduction to digital signal processing: Computer musically speaking. Singapore: World Scientific. Schnupp, J., Nelken, I., & King, A. (2011). Auditory neuroscience: Making sense of sound. Cambridge, Mass: MIT Press. Read More