SBUS was a functionality that was included with the original Symphony 64 PCIe release. SBUS let you connect multiple Macs together to pass audio back and forth between them using Symphony 64 PCIe cards. Unfortunately, it was no longer supported after the release of Symphony I/O. To use SBUS, you need at least 2 Macs (each Mac must be running OS version 10.5.8 or 10.6.8) and 2 Symphony 64 cards, along with at least one compatible Legacy Apogee converter (AD16x, DA16x, Rosetta800, or Rosetta200). If you meet all these requirements and would like to use SBUS, click here to download the compatible Symphony 64 installer. For a detailed description of SBUS, including how to set it up and use it, see pages 12-16 of the Symphony 64 user's guide.