Seismic charge is a bomb like weapon that can explode in space creating a unique blue circle after it goes off. However the image of the explosion is not the most iconic thing about the seismic charge, the thing that catches peoples attention the most is the satisfying noise that it makes. To many Star Wars fans this sound is very pleasing to the ears.
What really adds to the seismic charge sound is actually the absence of sound, if you listen closely you will notice that right before the explosion goes off, everything goes silent. This silence really adds to the diegetic feel and intensity of the charge itself. Sound designer Ben Burtt calls this absence of sound a “audio black hole” which is “an explosion so cosmic that the energy of the sound is unable to escape at the time of ignition, but is released a moment later” (Burtt filmsound). One fan asks Ben Burtt how exactly he got the explotion sound, but Mr. Burtt has chosen to keep that a secret. However he did let fans know that, “I originally made a variety of similar noises for what I called “Space Ether Explosions” for A New Hope. I used them as experiments, especially for exploding TIE fighters in the scene when Han and Luke are in the gun turrets. They were mixed into a scratch mix for the sequence, but George Lucas did not like them so I halted research” (Burtt Filmsounds). He explained that he later resurfaced these sounds and altered them in a secret way to make the iconic seismic charge sound.
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