If you want to learn or create spatial / immersive audio, the IEM Plug-in Suite is a great free resource to explore. Developed by the Institute of Electronic Music and Acoustics, this free and open-source audio plugin suite includes powerful tools for Ambisonics, binaural rendering, spatial encoding, decoding, visualization, room simulation, dynamics, reverb, and audio transformation.

The suite is especially useful for students, researchers, VR creators, sound designers, musicians, audio engineers, and anyone interested in 3D sound production. It supports Ambisonics up to 7th order and can be used for immersive music, 360° video, virtual reality sound design, spatial audio research, and experimental audio production.

Available plugins include: AllRADecoder, BinauralDecoder, CoordinateConverter, DirectionalCompressor, DirectivityShaper, DistanceCompensator, DualDelay, EnergyVisualizer, FdnReverb, GranularEncoder, MatrixMultiplier, MultiBandCompressor, MultiEncoder, MultiEQ, OmniCompressor, ProbeDecoder, RoomEncoder, SceneRotator, SimpleDecoder, StereoEncoder, and ToolBox.

These tools help users encode sound into the Ambisonic domain, decode Ambisonic audio for headphones or loudspeakers, visualize spatial energy, rotate sound scenes, simulate rooms, manage loudspeaker layouts, and create advanced immersive audio workflows.

The IEM Plug-in Suite is available for macOS, Windows, and Linux. It is suitable for use inside digital audio workstations such as Reaper and other supported DAWs.