Although you cannot open a 24-bit session on 16-bit hardware, Pro Tools 4.1 (and later) can convert a 24-bit session to 16-bit with the "Save A Copy In..." command. The result will be a 16-bit session file with 16-bit audio files.It is also possible to do 'offline' editing of the 24-bit session on a 16-bit system:- Convert the 24-bit session to a 16-bit session (session and audio files). - Transfer this complete (and independent) 16-bit version to your 16-bit system and open the session.- Do your edits- Save this as a 24-bit copy (session and audio files)- Copy (only) the new 24-bit session file to your PT|24 system- Open the new 24-bit session- Upon request, point the application to the original audio files (the names will be the same, except that the original files lack the "-16-24" ending. For example, when asked for "Electric Bass-02-16-24" select "Electric Bass-02."You will now have the edits you created on your 16-bit system applied to the original 24-bit session.(Keep in mind that this will not work for files you create while working on your 16-bit system, e.g. AudioSuite edits, etc.)