Apple Logic Pro 7 (TDM Guide) - Manual (Page 24)

24 Chapter 3 ESB TDM and EXS24 TDM
EXS24 samples reside in the computers RAM (although large samples can also be
streamed from hard disk, in realtime). Should any Instruments loaded into multiple
EXS24 instances use the same samples, RAM usage is unaffected. This intelligent
memory management ensures that any given sample is only loaded once into memory.
This allows the use of the same sound program (sampler instrument) or some/all of the
same samples in several EXS24 instances, with minimal impact on system resources.
Another point to bear in mind is that the EXS24’s sound generation engine is calculated
by the computer, and will therefore cause some CPU load. If you attempt to
simultaneously run numerous polyphonic EXS24 instances, you may notice a degree of
computer slowdown.
As an expected performance example: a Macintosh G4/800 (with sufficient RAM),
running 24 sampler instances, and using a combined 64 voices of polyphony should
not pose a problem.
ESB TDM
The ESB TDM allows the outputs of Logic’s DTDM “native” audio engine to be routed
into the inputs of the TDM mixer. This is done via Digidesign StreamManager. You can
activate the DTDM driver via the Audio > Audio Hardware & Drivers menu.