Then there is a boom of noise and static. In the third-floor office across the street from the Alfred Murrah building, shouts and screams and then distant sirens are heard.
"Everybody, let's get out of here," Ms Klaver calls out. "Watch the lights!"
The ceiling had fallen in, she told jurors yesterday. Cables and wires were everywhere and the electricity was still on.
The tape was played to jurors in the trial of Timothy McVeigh, accused of the Oklahoma bombing. "I thought the whole building was coming down on us," she said. "I didn't see there was any way we were going to get out."
Prosecutors used the tape to set the stage for their case, after the defence concluded its own opening statement on Thursday afternoon.
For months, Mr McVeigh's legal team has said suggestions that a wider conspiracy was involved in the bombing, from the American far-right fringe to a German neo-Nazi, with hints of bomb parts supplied by the IRA. But there was no mention of that when defence lawyer Stephen Jones stepped to the podium.
Instead, he spoke of mistaken identity and flimsy forensic evidence. He returned repeatedly to eye witnesses describing a second man, olive skinned and shorter than Mr McVeigh. It was the elusive "John Doe number two", declared non-existent by federal agents after one of the biggest manhunts in history.
It was not Timothy McVeigh, he insisted, who matched the figure who rented the Ryder truck. His fingerprints were not on the rental lease. Nor was it he who took a delivery of Chinese food at the local Dreamland motel.
The nitrates on him detected in forensic tests were found in guns and ammunition, Mr Jones said. "If Tim McVeigh built the bomb and put it in the truck, our proof would be that his fingernails, his nostrils, his hair, his clothing, his car, his shoes, his socks would have it all over them. They don't."
After prosecutors cited letters to show Mr McVeigh believed blood should be spilt in the name of "liberty", Mr Jones described his client as a "political animal". "His politics were open and known to anyone that spent any time with him," he said. His case, he said, would establish "not a reasonable doubt, but that my client is innocent."