"I have three different CDR drives connected to my Mac. Is it possible to have each of them burning a disc with Toast at the same time?"

Yes it is. Here is the procedure. (This information applies to Toast Titanium 5.x running on OS 8.6, 9.x or 10.x.)

1. First Duplicate the Toast Application. If you are in the finder you can choose the Duplicate option from the file menu. You will need a duplicate copy of Toast for Each recorder you want to use.

2. Launch each copy of the Toast application. If you launch a copy of Toast while a recorder is already burning a disk, it is likely this burn will fail and your disk will be ruined, so it is critical to launch each copy of Toast before beginning any burning.

3. In each Toast window select the recorder you want by initiating a bus scan, which can be done by clicking on the recorder name at the bottom of the window.

4. Add your data to each layout and begin burning.

Note: The only limitation here is the speed of the source drive. For example, it is likely that if you use an audio CD as a source for several copies at once, you will encounter a buffer under-run (unless your recorder supports buffer under-run protection).