Why does my receiver volume go from -db to +17db


On my NAD T 765 the volume goes from -90db to 17db. What does that mean? I thought 0db was silence and 35 t0 45db was an averave ambient level for a room.
georgeblaurock
Great post, Al. The line
db's are always derived from the ratio of two quantities
is noteworthy.

Regards,
If I had to guess I would say that 0 db is unity gain. Anything less than 0 the preamp is attenuating the gain of the source and anything greater than 0 the preamp is accentuating the gain of the source.
Agree with Rsfphil
Most volume controls which have that sort of numeric system "0" dB is unity gain. level coming in from the source is what goes out at zero db on the dial.