The current installer for the GCS Spectral Synthesizer. Install it, then activate with your license key.
GCS_Spectral_Installer.zip. Inside are separate folders for macOS and Windows..pkg installer and follow the prompts. It installs the AU, VST3, and AAX formats..exe installer and follow the prompts. It installs the VST3 and AAX formats./Library/Audio/Plug-Ins/~/Library/Audio/Plug-Ins/ — look in the VST3 or Components subfoldersC:\Program Files\Common Files\VST3\