Newbie questions but would appreciate the forum's comments...

1) Why does the main volume level go from -80db to +10db? Rather than, say, "0 to 90" or "1 to 10"?

2) If I push the volume too high, at what point will I cause the amp to distort (I have the 7100)? This may not be a valid question but my knowledge comes from my old receiver. Its volume nob went from 1 to 10 and at 6 the sound might start distorting and I even had the receiver shut off once. Will something like that happen if I push the 950 volume to +10db?