Great Italian prog band, Banco, did an all instrumental album called "Di Terra" in 1978.
It is one of the best integrations of a prog band and an orchestra I've ever heard. It doesn't just sound like a rock band fronting an orchestra. They play as an integrated unit with the orchestra.
And it's also not just orchestral arrangements of previous band material, or pop, or mainstream rock. It is modern sounding, fully realized orchestral music.
https://www.youtube.com/watch?v=5e4OkGAB4Ps
It is one of the best integrations of a prog band and an orchestra I've ever heard. It doesn't just sound like a rock band fronting an orchestra. They play as an integrated unit with the orchestra.
And it's also not just orchestral arrangements of previous band material, or pop, or mainstream rock. It is modern sounding, fully realized orchestral music.
https://www.youtube.com/watch?v=5e4OkGAB4Ps