David Foster, a Canadian composer, arranger and keyboardist, is producing the television show and an associated Christmas CD for Mr. Bocelli. Mr. Foster played the Tabernacle Organ for Saturday's recording session.
Mr. Foster approached the choir management earlier this year to ask if the choir could provide background vocals for Mr. Bocelli's performance of the song on the audio recording. A choir-only audio track was recorded and sent to the producer.
"They were absolutely blown away," Brother Barrick said, "with the sound and the quality they got back." The request then came to record video of Mr. Bocelli and Mr. Foster performing with the choir for the PBS special; hence the recording session in the Salt Lake Tabernacle.