In the Inception trailer, the music is not the most engrossing sound that is used. The music kind of takes a backseat to the non-diegetic long drum sounds in the background. this sound adds huge amounts of tension throughout the trailer as, it used used over and over again when something dramatic happens or the scene changes. It keeps the audience on edge and draws them into the film more. Also the dialogue used is like a commentary over the trailer adding to the complex storyline of the film and letting the audience know about the main character and the story. This helps the film attract the right audience that it wants for its film.
In the insidious trailer the use lots of repetitive diegetic sound is used to add huge amounts of tension. At the beginning they tick a clock and that ticks throughout the next 30 seconds of the trailer adding tension slyly in the background as the pace of the trailer builds up. After this they add the sound of a rocking horse throughout a few shots which starts to slow the trailer down before a big jumpscare. These use of diegetic sounds may be something we could think about using as they add so much and makes the music take a backstep to them.
In the Sinister trailer they use dialogue to help further the trailer as music plays quietly behind it, The speaking from Ethan Hawke is clips from throughout the film that have been cleverly put together to explain the plot of the film to the audience. The trailer also uses a loud screeching sound when it reaches a climatic jump scare to add to the fright that the audience will get.