It's now 1,800 (down from 2,750 seats) as quoted by several sources, for the Gaillard Center main performance auditorium, for the main the floor plus balcony / box seats along the side walls. Source: https://GaillardCenter.org/about-us/our-story/
I did Scott, there was not a definitive answer. I believe it's in the range of 1600...Thank you, Jim!
You should try Google
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