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Use Paulstretch to slow down audio by extreme amounts without changing the pitch.
Advice Note carefully that when you apply an effect to a time-stretched clip the changed speed of the clip will be automatically rendered.
  • If you apply an effect to a selection within a time-stretched clip then Audacity will split the original clip so that the selection can be rendered as part of applying the effect.
Alert If you apply this effect with an envelope present then there is a bug whereby the envelope is removed and the audio reverts to its full amplitude state prior to the effect being applied.
Accessed by: Effect > Pitch and Tempo > Paulstretch
Paulstretch 3-5-0.png

Stretch Factor

This sets how much longer the processed sound will be relative to the original. For example, setting this to 10 will stretch 1 minute of audio into approximately 10 minutes of audio, somewhat less at higher Time Resolutions.

Time Resolution (seconds)

In order for the effect to work, this value must be smaller than the selected area in the waveform.

Small values have good time resolution, but poor frequency resolution, so you may still be able to detect a rhythm (albeit a very slow rhythm). Large values have poor time resolution, but have great frequency resolution, so transients will disappear but pitch differences may be better preserved.

Usually, a value of 0.25 seconds is good for most music. Very large values (greater than 2 seconds) can be used for special effects such as "smearing" a song into a sound-texture, even if the Stretch Factor is close to 1.0.


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