Addressing creative notes
Often filmmakers give notes in the form of a solution rather than explaining what they want. For example, “can we lose the trumpet?” But losing the trumpet may not be the best musical choice. Whenever you get these types of notes, always dig a bit deeper and try to understand why the filmmaker is giving that note. When you understand the reason for the note (is the trumpet stepping on dialog? Is it too heroic? Or something else?) you’ll be able to come up with the most musical solution to address it (move the trumpet line so it doesn’t step on the note, change instrument, rewrite/reorchestrate those bars). You may want to read my blog post Just Because You Can Doesn’t Mean You Should, which expands on this topic.
Whenever getting a note take a moment to consider if it means a rewrite, or just a revision. This may involve asking the filmmaker a few pointed questions to get a deeper understanding of exactly what s/he wants. More often than not, creative notes mean revisions, not rewrites, so always start by trying to make adjustments rather than starting a rewrite from scratch. Tweaking existing material is much faster and more efficient than rewriting.
If you do need to rewrite a cue, make sure the new cue is meaningfully different than the original cue. Creating what amounts to another version of the same idea won’t get you very far. If you’re not sure where to start try finding some temp music to help you figure it out as described above in the What to do when you don’t know what to do section.
Addressing picture changes
Ideally when working on shoestring budget projects, you’ll be working to locked picture. But sometimes picture changes happen and you’ll need to adjust your music to fit the new cut. It’s usually fastest and therefore most efficient to address such changes with your printed audio rather than by going back into the DAW and your MIDI.
When conforming, especially if just conforming audio, I prefer to do it in ProTools. Below are some screenshots demonstrating how I like to do it.

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Making the edit may involve nudging things a bit for musicality. Keep in mind sometimes you may have to sacrifice a hit for musicality and that’s ok. Don’t get caught up in trying to maintain everything exactly as it was, the picture has changed and it’s OK for the music to change accordingly. Pick and chose the key moments that are most important to really nail on the sync, and sacrifice less important moments if you have to for musicality. Great as they are, hits aren’t nearly as important as making sure the cue feels natural and isn’t awkward in order to make those hits.