Richard, one mix rack will mix 128 channels, the main reason why we did dual rock in olive was to expand channel count sbove 64 due to the limitations of the Dsp.
With dLive you simply just add DX32 expander and can actually have up to 168 preamps connected. This is a much more cost effective and elegant solution as everything is on a single IP address and you’re not paying for more processing which you don’t need
Do you need more than 168 mic preamps? If so. You could add via one of the 5 option slots with 3rd party devices