Audio Track Dropdown Menu

From Audacity Development Manual
Revision as of 20:50, 24 December 2007 by Windinthew (talk | contribs) (added more text to explain the new images (but Pitch still needs doing))
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Track panel open.png
  Edit the name of the track

  Move Track Up or Down in the display

  Traditional display of audio material. It displays the amplitude of the audio over time. This is the default display mode.
  Like Waveform, it displays the amplitude of the audio over time, but here the vertical units are not linear, but logarithmic dB units.
  Displays the frequency spectrum of the audio over time.
  Tries to detect the pitch of the current audio and displays that information over time.

  Send playback of this single channel track to the left and right channels.
  Send playback of this single channel track to the left channel.
  Send playback of single channel track to the right channel.
  The selected track and the track just beneath it are turned into linked stereo tracks, so that edits are applied synchronously to both tracks.
  Turn one pair of stereo tracks into two single channel tracks, so they can be separately edited. Note that removing audio from one track will not shorten the other track: first apply Make Stereo Track to the pair if synchronicity is to be preserved.

  Change the sample format of this track. The result is that all newly written data for that track is written in this format, no matter what format the original material was in.

  Change the sample rate of this track. When importing audio, the track sample rate is set to that of the imported material. If your project rate is different, the audio will be automatically resampled to the project rate on playback or export.

Changing the sample rate always changes the speed and pitch of the audio, so only use it for a special effect or if the audio sounds at the wrong speed and pitch.



Waveform

The word 'Audacity' as a wave

This image shows a "Chirp" tone which stays at the same volume but gets progressively higher in pitch. You'd only see the pitch change on a waveform display if you zoomed in much further. This would then show the peaks of the waveform near the top and the bottom of the scale occurring much closer together at the end of the sound. The second part of the waveform is the word "Audacity" spoken aloud.

Is it worth having images of zoomed in at start and end, to show the pitch change?

Waveform (dB)

The word 'Audacity' as a wave, in dB mode

This image shows the same waveform but with a logarithmic method for scaling the amplitude. Notice the change in the vertical scale on the left of the track. This gives a better representation of the sound we hear, because the logarithmic scaling gives better detail for the fainter sounds (those further down the scale). It also shows more clearly than the waveform view how the energy of the Audacity word is naturally concentrated in the central "dac" part, and weakest at the end.


Spectrum

The word 'Audacity' as a spectrogram

This view displays how the amount of energy in different frequency bands changes over time. Higher frequencies are towards the top, lower frequencies towards the bottom. The blue colour is the least energy and the red is the most. This is the same waveform as in the previous two examples. The progressive increase of pitch in the chirp tone is vividly demonstrated by the upward sloping diagonal line. The second part of the plot, the word "Audacity" spoken aloud, again shows the greatest energy is in the center of the word.

Please improve the text of this note and state if (as I assume) this spectrum image is of the whole waveform (chirp then Audacity). -Thanks, Gale

You may want to compare this with a spectrum plot of this sound . That plot shows how much energy is in each frequency across the extract as a whole, but doesn't show how the frequencies change from beginning to end of it. There are several options for adjusting exactly how the spectrum is displayed.
Possibly add a link to part of some tutorial page describing how to track down clicks (using the spectrum view) and remove them. Maybe not in time for 1.4.0.

Pitch

The word 'Audacity' as a plot of pitch.
ToDo This image needs explanatory text