Limiting numbers for audio react/expressions

Hello there..
I want to make brightness to react to audio. I used expressions and ‘Expression pick whip (whip icon), it worked. But the problem is – keyframes starts from 0 and ends at ***, how can I limit them and decrease sensivity? For ex., when music is loud, brightness should be 120, bet when silent – 80.
Thanks.

via Video Editing Forums: Digital Director – Adobe Premiere, Premiere Elements, and After Effects http://www.videoforums.co.uk/adobe-premiere-premiere-elements-after-effects/43506-limiting-numbers-audio-react-expressions.html