hsc3-0.18: Help/UGen/ampDb.help.lhs
> import Sound.SC3 {- hsc3 -}
> let amp = map (2 **) [0 .. 15]
> let db = [0,-6 .. -90]
> map (round . ampDb . (/) 1) amp == db
> map (round . amp_to_db . (/) 1) amp == db
> zip amp db
> db_to_amp (-3) == 0.7079457843841379
> amp_to_db 0.7079457843841379 == -3