The stampede opened Friday and played a highly stylized version of "O Canada" in English and French, but many attendees complained they weren't able to sing along.
A choir re-recorded a more traditional version in English, which played Saturday, Sunday and Monday nights, the Calgary Herald reported.
Negative publicity about the English-only version led organizers to have the choir perform a traditional version in both official languages, which was played Tuesday night and will be through the duration of the annual rodeo-themed event that concludes Sunday night.
Kurt Kadatz, director of corporate communications for the Stampede, also issued a conciliatory statement to French speakers.
"If any of our guests are offended by what we did, we are sorry," he said.
There are 90,000 French-speaking people in Calgary and about 225,000 across Alberta, the report said.