Within a two-week period, I had the pleasure of singing in two very different, yet wonderful acoustic spaces. One was an early 1900s rural opera house and the other, a modern suburban church. One was built for secular purposes, the other religious; but in each case the room was built to be an auditorium - a room for several hundred people to listen.
Sometimes I'm stuck in an acoustically ugly space and do the best I can, with or without sound reinforcement. That's why I appreciate great rooms like these all the more; it's also when little or no amplification works best.
This experience gave me a very strong image and understanding: I was a mere string vibrating; the room was the great sounding board, the wooden box of a violin or guitar. I will practice playing the room as an instrument.