It generally runs up to macOS 10.12 (Sierra) . It will not run on newer macOS versions like High Sierra or Mojave due to the removal of 32-bit support and core architecture changes.
Improved content downloads and installation stability for OS X Lion and Mountain Lion . logic pro 9 update 918 download free
Logic Pro 9.1.8 is intended for legacy Intel-based Macs. It is widely considered that is the most stable operating system for this version. It generally runs up to macOS 10
Released in late 2012, version 9.1.8 was the final major stability patch for the Logic Pro 9 cycle. It addressed several critical bugs: Logic Pro 9
If you own the boxed Logic Studio 2 (DVD version), you need a specific standalone installer (often referred to as the DL1601 updater). While many official Apple Support download links have been retired, some legacy links like this one may still be active on Apple's servers.
How can I update Logic Pro 9.1.6 to 9.1.8? - Apple Community
Some users reported better CPU headroom and more efficient core balancing compared to version 9.1.7. System Compatibility & Requirements