Classe Audio CDP-102 CD Player User Manual

volume display If you elect to use the variable volume capability, you have two choices as to how
the volume setting is displayed.
Absolute is how most volume controls work, namely that a setting of “0”
indicates no sound, while larger numbers represent higher volumes.
Relative (THX) is the system preferred by the folks who bring you the
Home standards, wherein “0” represents a calibrated reference volume,
and deviations from that reference level are indicated as either positive or
negative numbers (louder and quieter, respectively).