Audio time stretching and pitch scaling

When you listen to music, you might notice that some songs sound faster or slower than others, or that the singer's voice sounds either higher or lower. These differences are caused by something called time stretching and pitch scaling, which are techniques used to change the speed and pitch of music.

Time stretching means changing the speed of a piece of music. This is done by either making the song play faster or slower than its original recording. For example, if you listen to a song at normal speed, it might take three minutes to play. But if you use time stretching to make it play slower, it might take four or five minutes to play, depending on how much you stretch it. Time stretching is used a lot to create special effects in movies, TV shows or commercials, and in music production, producers use it to fix a mistake in a song or to create a remix.

Pitch scaling, on the other hand, means changing the pitch of a piece of music. Pitch is the property of sound that determines whether a note sounds high or low. When you use pitch scaling, you make the notes in a song sound either higher or lower than their original recording. For example, you can use pitch scaling to change the key of a song, which means making all the notes sound higher or lower so that it fits better with the singer's voice.

In conclusion, time stretching and pitch scaling are techniques used to change the speed and pitch of music. By using these techniques, producers, musicians, and sound engineers can create special effects, fix mistakes, or even completely transform a song.