Verkar väl bara vara vissa som har 64 bit?
"*Note: Not all products are 64-bit or AAX compatible. AmpliTube 3, T-Racks 3, and CSR, are both 64-bit and AAX 32/64-bit compatible, however, the workstations are 32-bit plugins and not yet compatible with AAX 32 or 64-bit, including: SampleTank 2, SampleMoog, SampleTron, Sonik Synth 2, and Miroslav Philharmonik"
http://www.ikmultimedia.com/products/totalstudio3/index.php?pp=total-studio-3-bundle-specs