It was early morning on April 29 when Jakob Dwight ’s grandmother, Valeria Richards Maye, died in Alabama. It was that day, too, when he heard the cicadas sing near her home and it comforted him.

“I don’t know if they were out a few nights before,” he said. “I did not hear them the night before.”

It felt like some kind of connection to his grandmother: Describing the sound as almost like a ray-gun in a science-fiction movie or a thin metallic sheet rippling, Mr. Dwight said in an interview on Wednesday that he felt touched listening to the droning “in the way that if people lose a loved one, they tend to have magical experiences or at least imbue things in nature with kind of that spirit of the loved one.” He would go on to record the cicadas’ song the day after her funeral.

This spring, as two broods of cicadas emerge in a rare simultaneous event to produce a sound as loud as an airplane’s, Americans are feeling connected to nature and rejoicing — or covering their ears — as they listen to the song in their backyards.

While some find the buzzes, chirps and trills soothing or exciting, for others, the bugs are annoying or irritating. In one South Carolina county, residents even called the sheriff to report the strange, thunderous roaring.