Record­ing sam­ples mys­te­ri­ous Cuba sound at­tacks

U.S. em­bassy staff in Ha­vana ad­versely af­fected by noise.

The Atlanta Journal-Constitution - - FROMPAGE ONE - By Josh Le der man and Michael Weiss en stein

It sounds sort of like a mass of crick­ets. A high-pitched whine, but from what? It seems to un­du­late, even writhe. Lis­ten closely: There are­mul­ti­ple, dis­tinct tones that sound to some like they’re col­lid­ing in a nails-on- the- chalk­board efffffffffff­fect.

In a record­ing of what some U.S. Em­bassy work­ers heard in Ha­vana, a se­ries of un­nerv­ing in­ci­dents were later deemed to be de­lib­er­ate at­tacks. The record­ing, re­leased Thurs­day, is the fi­first dis­sem­i­nated pub­licly of the many taken in Cuba of mys­te­ri­ous sounds that led in­ves­ti­ga­tors ini­tially to sus­pect a sonic weapon.

The record­ings them­selves are not be­lieved to be dan­ger­ous to those who lis­ten. Sound ex­perts and physi­cians say they know of no sound that can cause phys­i­cal dam­age when played for short du­ra­tions at nor­mal lev­els through stan­dard equip­ment like a cell­phone or com­puter.

What de­vice pro­duced the orig­i­nal sound re­mains un­known. Amer i c ans afffffffffff­fected in Ha­vana re­ported the sounds hit them at ex­treme vol­umes.

Whether there’s a di­rect re­la­tion­ship be­tween the sound and the phys­i­cal dam­age sufff­fered by the vic­tims is also un­clear. The U.S. says that in gen­eral the at­tacks caused hear­ing, cog­ni­tive, vis­ual, bal­ance, sleep and other prob­lems.

The record­ings from Ha­vana have been sent for anal­y­sis to the U.S. Navy, which has ad­vanced ca­pa­bil­i­ties for an­a­lyz­ing acous­tic sig­nals, and to the in­tel­li­gence ser­vices. But the record­ings have not sig­nifi­f­i­cantly ad­vanced U.S. knowl­edge about what is harm­ing diplo­mats.

Of­fi­cials say the gov­ern­ment still doesn’t knowwhat or who is re­spon­si­ble for in­juries to its per­son­nel, but the U.S. has faulted Cuba for fail­ing to pro­tect Amer­i­can per­son­nel on its soil. Pres­i­dent Don­ald Trump’s chief of staffffffffffff, John Kelly, said Thurs­day in re­sponse to a ques­tion: “We be­lieve that the Cuban gov­ern­ment could stop the at­tacks on our diplo­mats.”

The Navy and the State De­part­ment did not re­spond to re­quests for com­ment on the record­ing. Cuba has de­nied in­volve­ment or knowl­edge of the at­tacks.

Not all Amer­i­cans in­jured in Cuba heard sounds. Of those­who did, it’s not clear they heard pre­cisely the same thing.

In sev­eral record­ings from Ha­vana taken un­der difffffffffff­fer­ent cir­cum­stances, all have vari­a­tions of the same high­pitched sound. In­di­vid­u­als who have heard the noise in Ha­vana con­firm the record­ings are gen­er­ally con­sis­tent with what they heard.

“That’s the sound,” one of them said.

The record­ing be­ing re­leased has been dig­i­tally en­hanced to in­crease vol­ume and re­duce back­ground noise, but has not been oth­er­wise al­tered.

The sound seemed to man­i­fest in pulses of vary­ing lengths— seven sec­onds, 12 sec­onds, two sec­onds — with some sus­tained pe­ri­ods of sev­eral min­utes or more. Then there would be si­lence for a sec­ond, or 13 sec­onds, or four sec­onds, be­fore the sound abruptly started again. A closer ex­am­i­na­tion of

one record­ing re­veals it’s not just a sin­gle sound. Roughly 20 or more difffffffffff­fer­ent fre­quen­cies, or pitches, are em­bed­ded in it, the AP dis­cov­ered us­ing a spec­trum an­a­lyzer, which mea­sures a sig­nal’s fre­quency and am­pli­tude.

To the ear, the mul­ti­ple fre­quen­cies can sound a bit like dis­so­nant keys on a piano be­ing struck all at once. Plot­ted on a graph, the Ha­vana sound forms a se­ries of “peaks” that jump up from a base­line, like spikes or fingers on a hand.

“What it is telling us is the sound is lo­cated be­tween about 7,000 kHz and 8,000 kHz. There are about 20 peaks, and they seem to be equally spaced. All these peaks cor­re­spond to a difffffffffff­fer­ent fre­quency,” said Kausik Sarkar, an acous­tics ex­pert and en­gi­neer­ing pro­fes­sor at The Ge­orge Wash­ing­ton Univer­sity who reviewed the record­ing with the AP.

Those fre­quen­cies might be only part of the pic­ture. Con­ven­tional record­ing de­vices and tools to mea­sure sound may not pick up very high or low fre­quen­cies, such as those above or be­low what the hu­man ear can hear. In­ves­ti­ga­tors have ex­plored whether in­fra­sound or ul­tra­sound might be at play in the Ha­vana at­tacks.

The record­ings have been played for work­ers at the U.S. Em­bassy to teach them what to lis­ten for, said sev­eral in­di­vid­u­als with knowl­edge of the sit­u­a­tion. Some em­bassy em­ploy­ees have also been given record­ing de­vices to turn on if they hear the sounds. The in­di­vid­u­als weren’t au­tho­rized to dis­cuss the sit­u­a­tion pub­licly

and de­manded anonymity. Cuban of­fi­cials wouldn’t say whether the U.S. has shared the record­ings with Cuba’s gov­ern­ment.

An­other big ques­tion re­mains: Even if you know you’re un­der at­tack, what do you do? Still dumb­founded by what’s caus­ing this, the United States has been at a loss to offfffffffff­fer ad­vice.

The em­bassy’s se­cu­rity of­fi­cials have told staff if they be­lieve they’re be­ing at­tacked, they should get up and move to a difffffffffff­fer­ent lo­ca­tion, be­cause the at­tack is un­likely to be able to fol­low them, the com­ment­ing in­di­vid­u­als said. The AP re­ported last month that some peo­ple ex­pe­ri­enced at­tacks or heard sounds that were nar­rowly con­fifined to a room or parts of a room.

At least 22 Amer­i­cans are “med­i­cally con­fi­firmed” to be afffffffffff­fected, the State De­part­ment says.

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