psai vs Steam Audio SDK

psai® is an interactive music engine for videogames, aimed at composers and developers creating adaptive soundtracks. Its playback logic can change intensity, recombine musical segments, pause, and respond to gameplay. The Unity edition is written in C# without native code, and the maker says it works on all Unity target platforms. The native C++ SDK is limited to Windows, with evaluation or licensing inquiries directed to the maker. The regular and Pro editions use the same Unity engine; Pro adds the standalone editor for creating projects from scratch. That editor is listed for Win/Mac and requires Music Engine Pro and Pro User Registration. Downloads include a demo soundtrack and eight free music themes. The maker says Unity use across a customer's projects has no further costs or royalties, with one copy required per company seat. However, the editor EULA limits users who have not purchased the engine through the Unity Asset Store to non-commercial editor use, including testing for future commercial use. The site also links to manuals, API documentation, tutorials, and a Unity forum.

Steam Audio SDK is a free toolkit for adding spatial audio to games and VR/AR apps. It renders positional audio binaurally using HRTFs to model sound direction relative to the listener. Environmental features include physics-based sound propagation, occlusion, reflections and reverb. The SDK can spatialize Ambisonics audio and rotate it with listener orientation, and developers can provide HRTFs in AES SOFA format. Multicore CPUs and supported GPUs can accelerate environmental simulation and rendering. Listed integrations include Unity, Unreal Engine, FMOD Studio, Wwise and a C API. The C API is intended for custom game engines, audio middleware and digital audio workstations, and can be called from languages that use external libraries. Supported systems include Windows, Linux, macOS, Android and iOS; SteamOS is also listed as a runtime platform. Integration requirements include Unity 2017.3 or later, Unreal Engine 4.27 or later, FMOD Studio 2.00 or later and Wwise 2023.1.0 or later. The project describes its development tools as being in Beta. Steam Audio is available free to developers, subject to a license agreement.