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Title: | The audio frequency analyzer |
Authors: | Magri, V. (1978) |
Keywords: | Audio data mining Oscillators, Audio-frequency |
Issue Date: | 1978 |
Citation: | Magri, V. (1978). The audio frequency analyzer (Bachelor's dissertation). |
Abstract: | In this project we are interested in audible sounds, therefore a brief study of the ear response to sound is required to lead to the audio-frequency range. It is seldom to find pure tones in nature; Sound waves generally are complex, varying in time frequency composition and intensity. In this project, however, analyses are going to be performed on steady sounds. Such sounds include, besides steady tones, random noise and many types of' machinery and vehicle noise which, although fluctuating in amplitude and frequency during short intervals of' time, have the same average spectrum at one time as another when integrated over sufficiently long intervals of' time. In practice a number of' different varieties of' analysers are used. The two types which are considered to be most practical and useful are the heterodyne type and the constant-percentage bandwidth type. In the latter case the tuning is provided by varying the values of a feedback network which is generally composed of' high-quality constants thus giving accurate values of' the resonating frequency. In the case of' the heterodyne type the tuning depends on the high frequency oscillator, and a relatively smell percentage shift in its frequency will result in a large percentage shift in the analyzer tuning. Most of this type of instruments must have their frequency reset each time measurements are made so that the frequency stability of a constant-percentage frequency type appears to be an important advantage; hence, the latter is preferred. This type of analyzer is more appreciated when it is considered that only one filter is required to scan the whole audio frequency range; there are other types which have to use a number of filters, each tuned for a different frequency band, in order to cover the same range. |
Description: | B.SC.ENG. |
URI: | https://www.um.edu.mt/library/oar/handle/123456789/96159 |
Appears in Collections: | Dissertations - FacEng - 1968-2014 |
Files in This Item:
File | Description | Size | Format | |
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B.ELEC.ENG._Magri_V_1978.pdf Restricted Access | 6.73 MB | Adobe PDF | View/Open Request a copy |
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