I was there, the vocals sounded fine. end roll was meh, but they lowered the key for Michi.
The reason Ayu was wearing the first dress was because her and the car with her outfit were running late, and Ayu got out of the car and dashed to the venue with the change of clothes coming later.
It was really hot, and hard to move. I had a lot of fun, but I was drained by the end from the heat mostly lol. I'm glad I got to go. There were about 1200? 1400? People. I forget the exact number. I was 453, and we were lined up by number to go in where we could stand anywhere. (No one really pushed and snaked to front which I appreciated. I hated that about the TA tour.)
I'm assuming the background vocals were utilized for two reasons. One because it was outside near the ocean (lots of outside noise) as well as there were no chorus members singing.
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