sound editor-they are responsible for all of a film’s sound elements, including dialogue, sound effects, automated dialogue replacement and more. Working in production as the film is being constructed
sound mixer -The sound mixer must decide what elements to emphasize and which to tone down. Working in post production.
Sound Editor: A sound editor is a creative professional responsible for selecting and assembling sound recordings in preparation for the final sound mixing or mastering of a television program, motion picture, video game, or any production involving recorded or synthetic sound. (https://en.wikipedia.org/wiki/Sound_editor_(filmmaking))
an audio engineer who oversees the production audio crew, mixes and balances the audio as it is recorded, and works to identify and solve the many problems that arise in this field: background noise, echo, distortion. (berklee.edu)
Sound editor oversees what happens to sound during production.
Sound mixer-
creative professional responsible for selecting and assembling sound recordings in preparation for the final sound mixing or mastering of a television program, motion picture, video game, or any production involving recorded or synthetic sound. (wikipedia)
Sound mixers edit the sound into the film. post-production
Sound Editor – someone who collects all the sound that a film requires and puts in other sounds to compliment the spoken words
Sound Mixer – someone who decides which sound elements to emphasize and which to tone down to meld the sounds seamlessly with the recorded dialogue during the post-production
Basically, the sound editor is responsible for all of a film’s sound elements, including dialogue, sound effects, automated dialogue replacement and more. It is not until all of these elements are brought together that the sound mixer can get to work.
Sound Mixer:
Once all the different sounds are edited together, the sound mixer comes into play. According to Variety, the sound mixer ultimately determines how an audience hears everything in a film. The sound mixer must decide what elements to emphasize and which to tone down. For example, there may be points in a film where the sound mixer feels the score should reign supreme. At other points, the sound mixer may emphasize the heavy breathing of a protagonist, perhaps during times of extreme stress.
Info sourced from: https://www.businessinsider.com/oscars-what-is-the-difference-between-sound-mixing-and-sound-editing-2017-2?r=US&IR=T
Sound editor: The sound editor is the creative genius behind a video production’s selected sound. The final sound assortments play an artful role in calibrating the sound to the visual production. Depending on the scope of the production, some sounds are real-life captured on location. -90seconds.com
Sound mixer: The senior-most sound position during pre-production and production. They serve as a sound recordist during filming, and are responsible for recording and balancing the audio effects on set.-Masterclass.com