I think the difference is now we use a DB scale.
which is quite confusing to our older habits a library is say 40 Db and a normal voice talking say 60 db.
Now our receivers and such are using these same measurements. So turning it up to say 50 is now normal. While on the older gear 1 to 10 scale 4 and 5 was already half the dial.

Though does that mean our equipment has a 100 Db max in return.?