Following the September 11 terror attacks, the church became a refuge and a symbol as it was mostly undamaged by the crumbling Twin Towers just blocks away.
The dust and debris destroyed the church's organ.
After more than 24 years since the damage, the 10-year multi-million-dollar project to build a new organ with 8,000 pipes and weighing 30 tons is complete.
"You can really just really make this whole place shake in a way that's just like almost deafening," assistant organist Alcée Chriss III said.
St. Paul's, which is part of the same congregation, became the resting grounds for military and first responders after the Twin Towers were attacked.
"There was dust, there was damage here," Chriss III said.
The organ at Trinity was no more.
For 15 years, Trinity had an electronic organ installed, with speakers hidden behind fake pipes in the choir loft.
It sounded like a recording of a concert instead of being at one.
"It did a passable job, but it wasn't the work of art that this is," Chriss III said.
It has injected new life into the current 180-year-old building.
"We wanted people to look back generations from now and be grateful for the work that we did and hopefully the decisions we mad. Hopefully, help people, not just ourselves in five years, but decades from now be inspired, come together and uplift each other," Organist Avi Stein said.
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