so I have a firewire 410 and after many hassles of trying to make aggragate devices with old interfaces work, I am willing to just get a second interface and connect it to my firewire 410. I want to be able to mic a drumkit, so that means many inputs. however, I have no idea how this works. When I go digital out of said new interface into my firewire 410, the daw will recognize that there are now such and such many more inputs? what is spdif, coaxical, etc? will pro tools recognize the new inputs even if the new interface isn't m-audio/digi? I am thinking of getting a saffire le or a presonus firepod. I will probably need about 8 inputs in total, so the interface can have 6. any suggestions?