When you have installed Reason 8.3 (or later version) and launch it for the first time, Reason automatically moves the Factory Sound Bank and Orkester sound bank to separate sub-folders in the following location on the hard disk (if they are not already there):
Mac:
/Library/Application Support/Propellerhead Software/Soundbanks
PC:
%programdata%\Propellerhead Software\Soundbanks
The factory sound banks will be located here so that Reason can be automatically updated in the future without affecting/deleting the existing factory sound banks. If Reason shouldn’t find the factory sound banks at this location, they will be automatically downloaded from the Reason Studios web site and put there.