A crossfade can rise in level when the overlapping sounds are similar enough to add together coherently. A constant-power shape is useful for unrelated sounds, but it is not automatically the safest choice for two aligned copies of the same music. Compare fade shapes and inspect the combined output before lowering the whole film's soundtrack.
Identify what actually overlaps
Solo the transition and name both sources. Are they unrelated recordings, adjacent musical passages, or duplicate copies of the same passage? Check whether one copy was moved by a small amount. A short offset can introduce tonal interaction as well as a simple level change, so calling every dip or swell a bad volume setting can hide the cause.
Audacity's Crossfade Tracks documentation distinguishes Constant Gain and Constant Power behavior for correlated and unrelated material. MIT's basic sound-editing teaching notes make the same mathematical distinction. These are starting models, not a promise of perfectly constant perceived loudness for every musical passage.
Make two controlled candidates
Work on copies with identical source positions, overlap length, channel layout, and clip gain. Apply a constant-gain fade to one candidate and an available constant-power fade to the other. Change no compressor, limiter, or music balance during this comparison. Otherwise several simultaneous changes make it difficult to explain an apparent improvement.
Listen at equal output settings before, during, and after the overlap. Inspect the mixed peak and any audible change in tone. If a limiter hides the rise, also compare a safe test render before that limiter where the editor permits it. Do not use a louder candidate's initial impact as evidence that it is smoother.
A proposed duplicate-versus-independent comparison
This experiment has not been executed for this guide. Prepare one pair from two exactly aligned copies of an authorized music excerpt, and another pair from different ambience recordings. Keep sensible headroom and use a comfortable listening level. Compare both fade shapes for each pair, recording the transition's peak and whether a swell or hollow sound appears.
The point is to observe how source relationship changes the result, not to publish a universal winning preset. Return to the real edit and choose a fade that preserves its intended musical or environmental continuity. If the overlap contains the wrong notes or a doubled spoken word, a different curve cannot repair that content decision.
Approve the rendered boundary
Render a short passage with context on both sides. Reopen it independently and verify the transition at ordinary listening level, then check the full soundtrack with dialogue restored. A locally tidy fade can still cover an important syllable when the complete mix plays.
Record the chosen shape and overlap with the project. This is an external audio-editing method for sound used alongside Imagild films, not an automatic crossfade feature claim. Approval requires a sensible combined level and intact content, rather than a particular preset name or two individually unclipped source clips.