Process of listening a performed music (live performance or recording) and using listening skills to write it down into a sheet music.
Many times there are orchestras that want to play musical pieces and the score is not available. Either because the score was never officially published or simply because there is only one audio record.
In those cases transcribing the music will help the orchestra to do a live concert and preserve the music so that future generations can play it.
Usually the composer of soundtracks creates the music digitally and sometimes it is necessary to record this music with a real orchestra. In this situation, making a correct transcription of the music will be necessary for the orchestra to be able to play it.
Study and analysis
Students sometimes listen to orchestral pieces that they would like to analyze for study. If there is no score, the analysis and understanding work will be more difficult. The music transcripor will be able to help the student by providing a score with an orchestration very close to the original to make it easier for him to study.