JUCE is a wide-ranging C++ class library for building rich cross-platform applications and plugins for all the major operating systems.
Cost / License
- Free Personal
- Proprietary
Platforms
- Mac
- Windows
- Linux

KFR is described as 'Is built for developers who need a powerful toolkit for audio and DSP applications. The framework is packed with ready-to-use C++ classes and functions for various DSP tasks from high-quality filtering to small helpers to improve development speed' and is an app in the development category. There are four alternatives to KFR for Mac, Windows and Linux. The best KFR alternative is JUCE. It's not free, so if you're looking for a free alternative, you could try JUCE or PortAudio.
JUCE is a wide-ranging C++ class library for building rich cross-platform applications and plugins for all the major operating systems.

PortAudio is a cross platform, open-source, audio I/O library. It provides a very simple API for recording and/or playing sound using a simple callback function.
RtAudio is a set of C++ classes that provide a common API for realtime audio input/output across Linux, Macintosh OS-X and Windows operating systems. RtAudio significantly simplifies the process of interacting with computer audio hardware.
AudioKit is the leading open-source audio framework. It powers millions of app installs. AudioKit allows developers to quickly add professional audio functionality to iOS, macOS, and Apple Watch apps.
