Sound is the most important aspect of horror trailers according to the document. Short snappy notes like a "dinging" sound in The Woman In Black trailer help build suspense by reminding the audience of a jack-in-the-box waiting to pop out. Silence is also commonly used in horror trailers right before a climax or jump scare. Contrasting happy music that then changes can catch the audience off guard to establish twists. The document concludes the author will use contrapuntal sounds and silence in their own trailer because research showed these were most effective at creating suspense.