> import Sound.DF

> do { n <- brown_noise_m
>    ; audition [] (out1 (n * 0.1)) }

> do { n <- white_noise_m
>    ; audition [] (out1 (n * 0.1)) }

> do { n <- brown_noise_m
>    ; let f = lin_exp n (-1) 1 64 9600
>      in do { o <- sin_osc f 0
>            ; audition [] (out1 (o * 0.1)) } }