Robert Everett-Green isn’t ready yet to pronounce on the acoustics of Toronto’s new Opera House: “I’ve been in the hall four times (five, if you count a hard-hat tour) and heard music from six different seats on three levels. It has been a steep learning experience so far, and I’m not just talking about the stairs up to the fifth ring. One thing I’m sure of is that it’s mighty interesting to have a new opera house on the block.”