Sometimes you need a sound effect or piece of music to reverb out. It could be a scream in a horror trailer, or something else that reverbs out over a cut to black. More commonly I use it when I want a piece of music I'm editing to end on a specific note to create a stop down moment in a trailer. Mostly it just gives me more options for editing music for trailers
This is very simple to do, but can take some finessing.
1. Find the precise note you want the cue to reverb out on.
2. Cut off everything after that note, or just before the next note starts. To get a clean reverb you don't want any sounds coming in after.
3. Make a cut a second or two before the note you're reverbing starts. This is to give some head to the clip so that you can fade from the "normal" clip to the "wet" clip with the reverb effect.
4. Nest that section into a new sequence.
5. Add a small fade at the end of the clip to avoid an audio pop, then add black slug into the new sequence. This will extend the duration of the nested clip.
6. Apply these reverb settings to the nested clip in the main sequence.
7. Fade between the "normal" and "wet" clips and tweak to you're liking. Usually it works best if you fade into the reverbed clip as late as possible so that you can't hear the effect before then.
8. Adjust the audio levels of the "wet" clip so you don't have a volume spike.
And that's it! This technique is a great thing to have under your belt because it opens up your options for editing music SIGNIFICANTLY. I always tell new editors to learn to edit and do all sorts of things to bend music to your will, and this is one of the key techniques I use to do just that.
Notes for Avid Media Composer, Final Cut Pro 7, and Final Cut Pro X.
Final Cut Pro 7
You can use the exact same steps for Final Cut Pro 7, just use these settings with the "Reverberation" Final Cut Pro filter. If it's not quite the sound you want, then experiment with the other presets.
Avid Media Composer
Since Media Composer can't nest clips the same way as Premiere and Final Cut Pro, after step #3 make an edit a few seconds after the end of the clip you want to reverb.
Select the clip along with the slug and create an Audio Mixdown.
Apply the D-Verb Audiosuite filter to the new clip, then adjust the reverb settings, audio levels and transition as needed.
Final Cut Pro X
There are a couple ways you can do this in Final Cut Pro X. You can do it the same way as before with a compound clip.
Open the compound clip and insert a "gap clip" that you then put at the end.
In the main sequence extend out the reverbed clip and apply the AUMatrixReverb filter to reverb out the audio. Trim the normal clip to the right, add a transition and that's it! I like this method because you can use the trimming tools to adjust where the cut is.
Then press "Shift-H" which in the Command list is "Retime: Hold" this will create an empty clip after that section.
After that you can apply the reverb effect! You can also adjust where the hold frame starts by clicking the edge of the green retime segment, and click "Edit" which will give you a source frame icon you can move.
This only applies if you're not doing the final audio mix yourself.
If for the final sound mix you're sending an OMF to the mixer be sure to "bake" in the reverb effect by exporting it as a separate AIFF or WAVE. Give the clip enough head and tail so that the sound mixer can smoothly transition to the reverbed clip. If an assistant editor is sending out final audio tracks, make sure to let them know that this needs to be done!
Alternately, your sound mixer most likely has vastly superior tools to make the audio reverb out, so the other solution is to give them the raw audio with a note about how it needs to reverb out.