To the casual observer, piano tuning must seem mysterious. Customers hear bong bong bong and see us wiggle the tuning hammer. They can’t see that our thoughts are aswirl with myriad judgments about where and how to place the 230 strings. One doesn’t tune just one string and go on to the next. We first set the A above Middle C to the A-440 Hz tuning fork, which is the standard frequency throughout most of the world for that note. From there, it’s a process of repeatedly comparing unisons, intervals, and octaves. We do that by counting beats, or pulses, created by two sound waves crossing. And, yes, it takes a long time to learn to hear them.

Pianos are hearty instruments, but they need routine care to withstand seasonal changes. In extreme climates, like in Saudi Arabia, where I lived for a year, pianos were adversely affected by the desert climate. Dry heat is killer to the wood, especially the soundboard and pin block. On better pianos, the pin block is made of twenty-plus layers (some have as few as five) of hard maple with cross-grain laminations. This alternation allows it to simultaneously hold the pins tight enough to keep them from losing tension yet loose enough so a tuner can move them smoothly. Steinway pins are notoriously tight. But, boy, do they hold their tune.

Blessed are the customers who have their instrument tuned twice a year. All pianos are built to sustain a certain amount of tension. So, when wood swells in spring, the soundboard pushes against the strings, causing them to go sharp. Conversely, when the heat is turned on in the fall, the instrument goes flat. Inattention in either case can result in a cracked soundboard and, in the case of Saudi Arabia, a pin block whose layers can look something like filo dough—separated and warped—leaves the pins with only a memory of torque. Better get out your wallet, cuz it’s big bucks to have that fixed.

According to the Piano Technicians Guild, about a quarter of all registered members are women, although there were far fewer when I started out. It requires upper body strength and a good dollop of patience. So, as a 24-year-old tuner in Chicago, I encountered many who doubted I could perform such demanding work. One person called after seeing my ad and asked for my husband. When I said I was the tuner, she said, “Oh . . . Oh. Well, okay.” A second asked if I was blind (many tuners are). I said, no, I was sighted but wore glasses. “I can take them off while I tune if you’d like,” I said. He hung up.

The most danger I faced was during a tuning in the locked mental ward of the VA hospital. I toiled for several hours on a sorry ol’ spinet in the visitors room, including replacing a broken string. I was crouched under the instrument when a patient shuffled up wearing slippers and baggy pajamas. He put his hand on my shoulder and said, “So you’re the lady piano tuner I’ve heard so much about.” (I’d been tuning throughout the VA complex.) I had no idea how to react to a patient in a locked ward but didn’t want to take any chances. I brandished my tuning hammer (a potentially lethal weapon) and told him to back off. Hearing the commotion, a nurse rushed in and scuttled the patient away. I was so unnerved by the situation that I punctured my hand with piano wire and needed a tetanus shot.

There are machines to help tuners. But many forgo them, arguing that music is perceived, not measured. Moreover, a machine comes with an “ideal” tuning. Problem is, no piano is ideal: Each one has its own personality and quirks. So, a tuning that suits a new Yamaha upright may not be what sounds best on Granny’s 100-year-old Mason & Hamlin parlor grand. That said, a machine would have come in handy when Pat Metheny’s band was warming up right next to me at a Columbus rock concert.

I’ve paid my dues working on umpteen nasally spinets and neglected uprights, and I found satisfaction in improving them all. But the time I tuned a 9-foot concert grand for Garrick Olson’s performance of Chopin’s Second Piano Symphony—that was the day my shoes left the ground.