My onkyo goes both ways.
It does the dB scale from about -60 to +10 i think and it uses a straight 0-100 scale as well.
Absolute and refernce scales i think they are called. Something like that.
On the 0-100 scale my reference level is marked at 82 when the volume screen reads 81, REF, 83....

"Those who preach the myths of audio are ignorant of truth."