I get that John, but it's not clear how the processors deal with inputs. For the 568, you manually configured how many bits you were feeding the processor. Does the G68 auto-sense?
The trouble is that I don't believe there is a way to set digital gain on a per-source basis where you know that the source is not coming out at 0dBFS. This is particularly true of satellite boxes where, for instance, you might want to set up separate phantom sources for listening to TV or radio stations with slightly different gains.
So perhaps a G18 is not needed; just the ability to boost the per-source gain of all inputs?