New Yorker staff writer Owen (Where the Water Goes: Life and Death Along the Colorado River, 2017, etc.) makes sense of hearing and its loss. An estimated 37 million Americans have lost some hearing, writes the author of this unusually informative and entertaining account. Fortunately, as one scientist told him, “there is no better time in all of human history to be a person with hearing loss.” In the 1700s, the hard of hearing used ear trumpets. Now there are many remedies for the two-thirds of Americans 70 or older who have lost some hearing. Hearing aids are improving, and inexpensive high-tech substitutes—including over-the-counter headphones—are available. Physicians may soon be able to reverse losses once considered hopeless. Himself a mid-60-ish tinnitus sufferer, Owen discusses his talks with numerous experts and patients and describes revealing visits to Massachusetts Eye and Ear, Connecticut’s American School for the Deaf, Bose Corporation, Starkey Hearing Technologies, and other research centers and companies. His highly anecdotal narrative explores every aspect of hearing, including its “Rube Goldberg machine” complexity, why most people wait more than 10 years to do anything about hearing problems, and the terrible effects of the noise of battle—one-fifth of all hearing aids sold in the U.S. are bought by the Department of Veterans Affairs. In clear, appealing prose, Owen explains how loud sounds—machinery, live music, etc.—can leave people no longer noticing smoke alarms, sirens, gunshots, and backup signals. Hearing loss is so common that the author discovers many friends and colleagues have the problem. Through their stories, he makes earwax interesting, explores sudden and single-sided deafness, and identifies the restaurants (always a challenge for the hearing-impaired) that are quietest (Chinese, Indian, and Japanese) and loudest (Mexican) in New York City. The book brims with useful advice: “Deafness is expensive. Earplugs aren’t.” A bright, upbeat, sometimes funny dive into a serious subject that will spur many readers to get their ears tested.