> Sound.SC3.UGen.Help.viewSC3Help "Done"
> Sound.SC3.UGen.DB.ugenSummary "Done"

> import Sound.SC3

> let {x = mouseX KR (-1) 1 Linear 0.1
>     ;e = linen x 0.1 0.1 0.5 DoNothing
>     ;o1 = sinOsc AR 880 0 * 0.1
>     ;o2 = sinOsc AR 440 0 * e}
> in audition (out 0 (mce [done e * o1,o2]))