Harvey Mason Jr. and Whitney Houston
Courtesy Harvey Mason Jr.
02/15/2012 at 04:00 PM EST
Arriving at Mason Sound recording studio in North Hollywood on the evening of Feb. 7, Whitney Houston was all smiles and feeling "really positive," producer Harvey Mason Jr. tells PEOPLE.
"We stood around and joked, listened to music, and we got her this throat coat tea she likes," says Mason, who worked with the singer on her last recording of the up-tempo record "Celebrate," a duet with Jordin Sparks
for the soundtrack of the upcoming film Sparkle
"Then she got in the booth, started her vocal session with a prayer as she always did, and worked for about three to four hours. We ended the session dancing around the control room while she said 'Turn it up! Turn it up!' She was so fun-loving."
Houston, who died on Feb. 11
at age 48, and Sparks, 22, didn't record the duet together. But Houston – who'd recorded the song over a few sessions in the past couple of weeks – "wanted to make sure Jordin had enough time to shine on the song," says Mason. "She loved all of the female singers coming up."
Mason adds that in the studio Houston gave a great performance. "She said 'Don't make anything less than perfect.'"
Asked if Houston could have been putting too much pressure on herself during her final days
, Mason says, "She was excited, not overworked. I've been around her when she is overworked. She comes into the studio and is kind of down and quiet and just wants to get in and out. This was not like that. Whitney was worried about her fans, but there was no undue pressure."
In fact Houston was bursting with optimism. "She talked about Sparkle
, Waiting to Exhale
and working on her new solo record," says Mason. "And she was excited for Clive [Davis's] party
It is yet to be determined if Mason will release "Celebrate" because Houston had another session before the song would be finalized. But he assures, "she sounded really good."