Signals PDF
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Uploaded by ComplementaryVerdelite3564
HTW Berlin - University of Applied Sciences
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Summary
This document provides information about sine waves, frequencies, and related topics in audio engineering. It details concepts like frequency, period duration, and wavelength, and also includes examples of different audio signals, such as white noise and pink noise.
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50Hz 1kHz 100Hz 1kHz 500Hz 1kHz 1kHz White 2kHz Noise Pink 5kHz Noise 10kHz 15kHz 20kHz Sine Wave Parameters Voltage U Time t Frequency: The frequency describes the amount of oscillation periods per time-unit. In...
50Hz 1kHz 100Hz 1kHz 500Hz 1kHz 1kHz White 2kHz Noise Pink 5kHz Noise 10kHz 15kHz 20kHz Sine Wave Parameters Voltage U Time t Frequency: The frequency describes the amount of oscillation periods per time-unit. In audio-engineering exclusively seconds used for time-unit. The unit of the frequency is the Hertz (Hz). But also multiples of it are used: Kilohertz (1000Hz = 1kHz), Megahertz (1.000.000Hz = 1MHz). 𝑓 = 1Τ𝑇 Period Duration: The period duration is the time in wich the sine-wave has a full passage. The unit is the second. 𝑇 = 1Τ𝑓 Wavelenght: The wavelenght is the spatial correspondence to the period duration. It is calculated from the speed of the propagation and the frequency: 𝑐 λ= 𝑓 Sine Wave The sine-wave is the simplest known waveform. It is also called harmonic oscillation. A harmonic oscillation consist of only one frequency. A complex oscillation (every periodic signals except sine/cosine) can be simplified seen as a mixture of different sine-waves, which can be displayed with a measuring instrument. Sectrum view of a 440Hz sine-wave A sawtooth wave with a fundamental tone of 440Hz Notice: The sine wave is the purest form of sound! To devide the signal in its single frequency components, an often used algorithm, the Fast Fourier Transform (FFT) is applied. You find this algorithm e.g. in FFT-Eqs, Spectral Cleaner and every application which needs to know of what the signal precisely consist. On the sine wave the different values can be abstracted: 1: Ueff - Effectiv Value, RMS 2: û - Peak-Value, Amplitude 3: Uss - Peak-Peak Value For sinusoidal alternating voltages (and only there!) The following equation applies: 1 𝑈𝑒𝑓𝑓 = ∗ 𝑢ො 2 Bildquellen: Handbuch der Tonstudiotechnik, Band 1 Dickreiter et.al., Saur 2008 Friedemann Kootz, 2012 Handbuch der Tonstudiotechnik, Band 1 Dickreiter et.al., Saur 2008 Modifikationen Friedemann Kootz, 2012
