PaulStretch

PaulStretch: Free Audio Processing Software for Extreme Sound Stretching

Free audio processing software allowing sound stretching without changing pitch, turning short clips into extended ambient textures

What is PaulStretch?

PaulStretch is a free, open-source audio processing application developed by Nasca Octavian Paul that allows users to stretch audio files to extremely long durations without changing the original pitch. It works by analyzing the harmonics and dynamics of the audio and synthesizing an extended version that retains the tone and texture of the original.

PaulStretch is most commonly used by musicians, sound designers, and audio engineers to create long, evolving ambient textures and soundscapes from existing recordings. For example, stretching a piano tone or vocal sample into an immersive, drone-like bed. Stretch factors of 4x up to 1000x are possible.

Unlike simpler pitch-preserving stretch algorithms, PaulStretch utilizes a configurable overlapping technique that maintains formants and transients in the audio. This helps the extended sounds retain detail and clarity rather than devolving into a blurred smear. The interface is straightforward with the main parameters being stretch factor and various sound quality settings.

In addition to stretching and texturizing sounds, creative uses for PaulStretch include slowing down audio to uncover hidden details or harmonics and even synchronizing extremely slowed down music with astronomical events occurring over very long timescales. The results can be surprisingly listenable despite the massive stretch amounts.

PaulStretch is available as VST/AU plugins for Mac/Windows as well as a command line utility. It is capable of handling large audio files and long render times efficiently. The simple but powerful concept behind PaulStretch makes it a useful tool for electronic musicians, multimedia artists, and other audio manipulators.

PaulStretch Features

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