![]() This assumes you are already familiar with how to open an audio file in Audacity. ![]() This option has no effect and is grayed out when the Pitch (EAC) algorithm is selected.This is a quick tutorial and list of actions that will get the first time user up and running with Audacity, for the purpose of reviewing their audio files visually, with spectrograms. Zero padding factor: Larger values give finer interpolation of the colors along the vertical axis, at the expense of more computation time.All methods give broadly similar results. 'Rectangular' is slightly faster than other methods, but introduces some artifacts. Window type: Determines precisely how the spectrogram is computed.Larger FFT window sizes give more low frequency resolution and less temporal resolution, and are slower. Window Size: The dropdown menu lets you choose the size of the Fast Fourier Transform ( FFT) window which affects how much vertical ( frequency) detail you see.The aim was to allow automated comparison of sound files so that two versions of the same tune could be recognized as being similar, even if played in different keys, or on different instruments. The EAC Algorithm was developed to produce a mathematical representation of the changes of pitch in a piece of audio. Pitch (EAC): Highlights the contour of the fundamental frequency (musical pitch) of the audio, using the Enhanced Autocorrelation (EAC) algorithm.This mapping to reassigned time-frequency coordinates is very precise for signals that are separable in time and frequency with respect to the analysis window. Reassignment: The method of reassignment sharpens blurry time-frequency data by relocating the data according to local estimates of instantaneous frequency and group delay.Measured in Hz, higher frequencies have higher pitch. Frequencies (default): Audio frequency determines the pitch of a sound.Scheme: Choice of two colorways or two grayscale settings.This option has no effect and is grayed out when the Pitch (EAC) algorithm is selected. You get less gain at lower frequencies as well. Frequency Gain (dB/dec): A positive value here gives some extra gain to higher frequencies (above 1,000 Hz), as they tend to be smaller and so cannot be seen as well.The default is 80 dB and means that you will not see anything for signals 80 dB below the value set for "Gain". Range (dB): Affects the range of signal sizes that will be displayed as colors.The default is 20dB and corresponds to a -20 dB signal at a particular frequency being displayed as "white". If the display has too much "white", decrease this value. ![]() For small signals where the display is mostly "blue" (dark) you can increase this value to see brighter colors and give more detail. ![]() Gain (dB): This enables you to increase / decrease the brightness of the display.A good use of this setting is in speech recognition or pitch extraction, where you can hide the visually unimportant highest frequencies and focus on the lower frequencies. Irrespective of the entered value, the top of the scale will never exceed half the current sample rate of the track (for example, 22,050 Hz if the track rate is 44,100 Hz) because any given sample rate can only carry frequencies up to half that rate. The value can be set to 100 Hz or any higher value. Maximum Frequency: This value corresponds to the top of the vertical scale.The default value of "0" here will be treated as "1" when using "Spectrogram Logarithmic" view mode because a logarithmic scale cannot start at zero. Frequencies below this value will not be visible. Minimum Frequency: This value corresponds to the bottom of the vertical scale in the spectrogram.It is for making the same displays of Pitch possible as in earlier versions of Audacity. Period: is the previously undocumented scale used by Pitch (EAC) view.It is implemented as a function ERBS(f) which returns the number of equivalent rectangular bandwidths below the given frequency "f". ERB: The Equivalent Rectangular Bandwidth scale or ERB is a measure used in psychoacoustics, which gives an approximation to the bandwidths of the filters in human hearing.It is related to, but somewhat less popular than, the Mel scale. Bark: This is a psychoacoustical scale based on subjective measurements of loudness.Mel: The name Mel comes from the word melody to indicate that the scale is based on pitch comparisons.See Spectrogram View for a contrasting example of linear versus logarithmic spectrogram view. Logarithmic: This view is the same as the linear view except that the vertical scale is logarithmic.Linear The linear vertical scale goes linearly from 0 kHz to 20 kHz frequency by default.
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