This application/plugin is based on the PaulStretch algorithm. (Paul’s Extreme Time Stretch, originally developed by Nasca Octavian Paul), and specifically the PaulXStretch version from Xenakios. The UI has been updated and adapted for various screen sizes.

PaulXStretch is only suitable for radical transformation of sounds. It is not suitable at all for subtle time or pitch corrections and such. Ambient music and sound design are probably the most suitable use cases. It can turn any short audio into an hours long ambient soundscape without batting an eye!

Works as a standalone application on macOS, Windows, Linux, and iOS, and as an audio plugin (AU, VST3) on macOS, Windows and iOS (AUv3).

There are binary releases for macOS and Windows available at sonosaurus.com/paulxstretch or in the releases of this repository on GitHub.

For now, you can build it yourself following the build instructions below.

Source code is now maintained at:

https://github.com/essej/paulxstretch

To build from source on macOS and Windows, all of the dependencies are a part of this GIT repository, including prebuilt FFTW libraries (for Mac/Win only) The build now uses CMake 3.15 or above on macOS, Windows, and Linux platforms, see details below.

Make sure you have CMake >= 3.15 and XCode. Then run:

./setupcmake.sh
./buildcmake.sh

The resulting application and plugins will end up under build/PaulXStretch_artefacts/Release when the build completes. If you would rather have an Xcode project to look at, use ./setupcmakexcode.sh instead and use the Xcode project that gets produced at buildXcode/PaulXStretch.xcodeproj.

You will need CMake >= 3.15, and Visual Studio 2019 installed. You'll also need Cygwin installed if you want to use the scripts below, but you can also use CMake in other ways if you prefer.

./setupcmakewin.sh
./buildcmake.sh

The resulting application and plugins will end up under build/PaulXStretch_artefacts/Release when the build completes. The MSVC project/solution can be found in build/PaulXStretch_artefacts as well after the cmake setup step.

The first thing to do in a terminal is go to the Linux directory:

cd linux

And read the BUILDING.md file for further instructions.

Copyright (C) 2022 Jesse Chappell

Copyright (C) 2017-2018 Xenakios

Copyright (C) 2006-2011 Nasca Octavian Paul, Tg. Mures, Romania

If you would like to contribute anything via pull requests, please do so from the develop branch of this repository.

Released under GNU General Public License v.3 license with App Store license exception. The full license text is in the LICENSE file. Paul Nasca, Xenakios and Jesse Chappell all explicitly permitted the license exception clause. The AAX plugin and the version distributed on the iOS App Store by Sonosaurus is not built with FFTW, and the JUCE commercial license applies there.

It is built using JUCE 6 (slightly modified on a public fork), I'm using the very handy tool git-subrepo to include the source code for my forks of those software libraries in this repository. FFTW is required, but statically built libraries are included in deps for easier building on Mac and Windows.

Dependencies that are referenced via git-subrepo in this repository are:

• (deps/juce) https://github.com/essej/JUCE in the sono6good branch.
• (deps/clap-juce-extensions) https://github.com/free-audio/clap-juce-extensions in the main branch.
• (deps/clap-juce-extensions/clap-libs/clap) https://github.com/free-audio/clap in the main branch.
• (deps/clap-juce-extensions/clap-libs/clap-helpers) https://github.com/free-audio/clap-helpers in the main branch.