I'm not sure that SoundEdit 16 is an ARTA program... the only DSP-aware sound app that I know of for sure is (old versions of) Deck.

You can do what you want, but only with certain DSP cards... the common ones like PhotoEngine and Thunder {II,IV} GX use their own software instead of ARTA.

I guess the NuMedia and Spectral Innovations NuBus DSP boards support ARTA, so with those you'd be able to do what you want. Also, they'll give you luvvin' with the AV DSP Power photoshop plug-in.