"It's New Zealand's largest annual classical music competition and it's a world-class event with world-class entrants," she said.
Mrs La Grouw said she expected tickets to Sunday's finals to sell out, with all 700 seats filled up.
"We're certain Sunday will be a sell-out. It always has been. So I'd advise people to get in quick if they'd like to come along."
"It's going to be world-class entertainment, with hugely talented entrants.
"It will make for a wonderful evening of music."
The arias will feature a variety of categories, including the Maori Song class which has a top prize of $3000.
The competition begins 9.30am today. The final on Sunday begins at 7.30pm. Tickets are available from Ticketmaster. For more information or a programme, visit www.nzaria.co.nz
Details
What: New Zealand Aria.
Where: Sir Howard Morrison Performing Arts Centre.
When: Today, from 9.30am to 9.30pm, tomorrow from 8.30am to 9pm and Sunday from 9am to 12.30pm, finals 7.30pm.
Cost: Adult $55, senior $40 and student/child $40