Sounds like the sound effect they use on the simpsons when something gets irradiated. Play the M2 key (A#1) when octave is set to 3. Adjust peak to your liking. It just adds more bass.
The quick Attack and decay of the EG resemble a kick drum among the looping bass. Mess with the slide edit mode on the first four steps for variations in the "kick". I added a simple reverb and filter delay to the audio sample.