Volume and Max volume adjust the same thing.
Actual volume = main volume ring number × Max Volume %. For example: if the Main Volume is 80, but the Max Volume % is 70, then the Actual Volume is 80 × 70% = 56.
We did it like this so that even if you have to set your Max Volume at say 50% you still get the granularity of adjustment that you would expect. If we had made it so that Max Volume simply limited the range on the main volume ring (i.e. you couldn't raise it above 50%), then adjusting the volume by 1, would have been too big a dB change in some systems.
Note that Volume and Max Volume interaction is not only for Leedh - it is for the traditional volume algorithm too. The purpose of Max Volume is to limit the overall output so that an accidental finger-tap can't suddenly overpower speakers.
It's described in our General Settings manual page here:
LUMIN General Settings
With reference to your question about this 94% observation - 1) that means the 'Actual Volume' and 2) that would be with also another volume control in the chain (on their pre-amp). It's something to experiment with rather than a rule. If LUMIN Leedh volume was the
only volume control in the chain, then obviously it would be adjusted to taste.