If you’ve been to Macy’s on Market Street, you know the Wanamaker Grand Court Organ, the largest operating musical instrument in the world. But you may not know that it recently got a face-lift — one that’s debuting on Saturday.

The restoration targeted the grand organ case, the 117 gold pipes visible above the marble balcony on the second story of the store’s Grand Court. The pipes were repaired, smoothed, cleaned, and painted to match their original color, a warm shade of white.

To celebrate the completion of the project, which started in March, Macy’s and the Friends of the Wanamaker Organ will hold a series of public concerts from 11 a.m. to 8:30 p.m. on Saturday, which also marks the 26th Wanamaker Organ Day.

Fresh as they may be on Saturday, the organ case’s pipes are just for decoration. The 28,750 pipes that actually play are hidden behind, in chambers that span from the second to the seventh floor. In honor of the instrument’s rich history, here are seven other facts you may not know about the Wanamaker Organ.

Visitors can attend the unveiling of the Wanamaker Grand Court Organ’s new facade at 11 a.m. Saturday, June 1. Organist Peter Richard Conte will perform with the Philadelphia Brass and other guests. In the afternoon, various organists will take to the keys. The day will conclude with a grand evening concert ($50) by Conte and Ken Cowan, a Canadian organist. For tickets, go to wanamakerorgan.com.

In its original form, the organ was very loud

The organ as we know it today differs quite a bit from what organ architect George Ashdown Audsley designed in 1904 for the St. Louis World’s Fair. Back then, it was a mere 10,000 or so pipes.

Nonetheless, when the instrument was played at the fair, it knocked plaster from the ceiling and panicked the crowd, according to Ray Biswanger, executive director of the Friends of the Wanamaker Organ.

“Alexandre Guilmant, the organist, kept playing and restored calm. He played 40 different recitals, all from memory. It was unheard of.”

Building the organ was extremely expensive. Buying it was (maybe) not.

To build the organ for the World’s Fair, it cost $105,000 — or $2,927,944 in today’s money. Unsurprisingly, it bankrupted the Los Angeles Art Organ Company, the builder tasked with its construction.

It went into a warehouse after 1904 and sat there until John Wanamaker bought it in 1909, reportedly for “next to nothing.” The organ shipped to Philly on 13 train cars and took almost two years to install.

The first performance it gave in Philadelphia was a regal one

The organ was first played for the public in the Wanamaker Building on June 22, 1911, at the exact moment when King George V was crowned at the Westminster Abbey across the Atlantic Ocean.

Despite the instrument’s size, the Wanamakers didn’t think the organ was loud enough

Rodman Wanamaker, John Wanamaker’s younger son, was a bit of a spendthrift, according to Biswanger. He also loved the arts and significantly enlarged the organ — by more than 18,000 pipes, made with only the finest materials. Under his watch, the organ expanded to include a special console with six keyboards and a full strings stops section, resembling that of an orchestra’s strings section.

“[Rodman] wanted to create an art organ that would last through the ages,” Biswanger said. “The same people who built it were hired again. They opened their own organ factory on the 12th floor. Certain parts of the store were just walled up and they made chambers out of sales areas. The whole store is kind of an archaeological paradise.”

Rodman died in 1928 without hearing the finished product — the organ was completed in 1931. But while he was alive, he said he would “continue to enlarge, improve and beautify [the organ] until it combines the grandeur of a great organ with the tone colors and beauty of a great symphony orchestra.”

It inspired some of the music in Disney’s ‘Fantasia’

In 1919, the Wanamakers invited the Philadelphia Orchestra and its illustrious conductor, Leopold Stokowski, to perform in the department store, with the organ backing them. Four such performances were given between then and 1926, and Stokowski was reportedly inspired to arrange organ works for the orchestra as a result of the collaboration. That included his transcription of Bach’s Toccata and Fugue in D Minor, which was eventually set to animation in 1940 in Walt Disney’s Fantasia (in which Stokowski and the orchestra were featured heavily).

Its pipes have an impressive range — in size

The circumference of the organ’s largest pipe is so wide that a Shetland pony once posed for pictures inside it. That same pipe measures a respectable 32 feet long. The smallest pipe, in comparison, is a quarter-inch long.

The organ had its own radio station

The Wanamaker organ had its own broadcasting station from 1922 to 1928. Those broadcasts used special microphones and were the first to feature the pipe organ on the air. This allowed people in the United States, as well as in Canada, Europe, Africa, and Australia, to enjoy its music.