American Music Theatre (AMT) is a spectacular pop-music/live venue...and it absolutely depends on amplified sound. Once, at a rehearsal without mics, I could not hear the singers from the first row.
The Lancaster Symphony would prefer a venue tuned to live music, which depends on reverb/blending. Voice (spoken word) , which requires dead sound to avoid articulation confusion, is a different acoustic concept. AMT is modeled after Sight and Sound and Branson/Myrtle Beach venues.
But to have a dedicated 1200-1600 seat concert hall (as the Symphony would like) would only make sense if the overall city residential demographic were upscaled, and the parking and routes to the center were clean and easy.