Behind the sweeping walls of Union Terminal's rotunda, something beautiful has been holding its breath.
Since the late 1980s, the train station housing the Cincinnati Museum Center has been home to an enormous pipe organ. The first concert in the 1990s drew more than a thousand people.
The concerts paused in 2016, when Union Terminal underwent a massive renovation. The pandemic kept them from coming back. But starting this week, the organ will breathe again.
Harley Piltingsrud is the Museum Center's organ curator. He stands in the empty rotunda on a recent evening listening as a computer sends signals to the organ's pipes and expression shades to put the instrument through its paces. He says the 106-foot-tall dome makes for a unique experience.
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"We had to actually treat part of this area with sound absorbing material to bring the reverberation rate down to five-and-a-half or six seconds," he says as he points to the portion of the dome near the terminal's entryway. "Which is similar to large cathedrals in Europe."
The organ's keyboard console waits in a glass display case until it's ready to be wheeled into the middle of the rotunda floor. The rotunda's curved back wall hides most of the organ's lungs — that is, the massive system of pipes and blowers which push air through them. Piltingsrud walks behind a present-day concession area and through an unmarked door.
The hum of air compressors grows louder as he enters the room.
"The air supply for this part of the organ," he says, gesturing toward the source of the noise. "These are all pressure regulators up in here, and these are the blowers, as we call them. They're compressors that develop the pressure for operating the organ."
He points to another part of the small room that operates something like the organ's nervous system.
"This is where signals from the console come in and then disperse out to all the pipe chambers."
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There are actually two concert organs in the terminal, both built by renowned organ builder E.M. Skinner in 1929, the same year construction began on Union Terminal.
Together they're comprised of more than 4,500 pipes simulating flutes, oboes, cellos, trumpets, harps and other instruments. Some weigh as much as a half ton.
They're made of various woods and metals chosen for their tonal qualities. Perched in a small room two stories up, Piltingsrud points to a speckled silver pipe made of zinc designed to simulate a harp.
"Zinc has a lot of strength, but it also has the right timbre to it as well," he says, lifting a small piano-style hammer and letting it fall. The pipe lets out a resonant ding.
The Museum Center's main organ belonged to the Immaculate Conception Church in Philadelphia before coming to Cincinnati. The second, smaller set of pipes, known as the antiphonal division, is situated above the doorways to the Cincinnati History Museum. It was the household organ for industrialist Powel Crosley at his College Hill estate.
The setup gives listeners an immersive, surround sound experience. Though Piltingsrud uses a computer to test the organ, a live organist will be at the keyboard soon.
"The first organist in our series this year, Isabelle Demers — she's French Canadian — she played here once before. She played the Harry Potter Suite, and she had the music swirling around in here, between the antiphonal and the percussion and the harps. It was mysterious. It was wonderful."
Demers returns Nov. 29 to play selections from the Harry Potter Suite and Star Wars, as well as Stravinsky's Firebird Suite and other selections. More concerts will follow in January and April next year.
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In the meantime, there is still fine-tuning to do. Piltingsrud is the driving force behind the organ, having designed its hidden systems and installed additions and working on stabilizing humidity and temperature in the pipe sections. For him, it's a labor of love.
"I've got over 25,000 hours of volunteer time in this project," he chuckles. "But I'm a physicist by training and strong in the engineering disciplines I'd say. So it fits together to a certain extent, you know?"
Piltingsrud sits in the middle of the dim, empty rotunda and admires the sounds of a Debussy piece the organ is playing.
"You have to have perseverance in any aspect of organ building. They're so involved and so time-consuming. Not for the faint of heart."