I have the Dr 880 as well. I use the audio for recording because it has its own mixing and EQ through the TSC. If you wish to use it through MIDI, you will not get the same sounds unless you spend a bit of time adding plugins to shape the sound of the Garage Band drums. But to get each sound on a seperate track would be easier through MIDI because you can select each drum part, the create a new region on a track and paste just that part seperately. If you then wish you can RE-Merge these seperate MIDI tracks and import them back into the drum machine for audio playback. It will only send controll information. No audio adjustments can be made from Logic to Dr. 880. Hope this helps.