Scottie Upshall scored his second goal of the season, at 9:35 of the first when his shot from the left wing beat Avalanche goalie Jose Theodore to the glove side.
Mason, Nashville's backup goalie, improved to 3-1 while was playing for just the fourth time this season. His previous high for saves in a game was 38, also against Colorado, on April 4, 2004.
Nashville improved to 10-4-1, with seven victories - including five of its last seven - by a single goal.
Theodore made 30 saves as Colorado was shut out for the first time since a 2-0 loss at Calgary on April 13.
Nashville was whistled for three penalties in a span of 1:01 about three minutes into the game, but Colorado failed to take advantage. The Avalanche did not get another power-play opportunity until 1:54 into the third period, and finished 0-for-7 on the power play.
The Predators, who were shut out 3-0 at Detroit a night earlier, were at home for the first time since Oct. 26 and improved to 3-1-1 at Gaylord Entertainment Center.
Notes: Colorado, which last played Tuesday at home, warmed up in its practice uniforms because its game sweaters had not arrived. The equipment was flown in and arrived in time for the game. ... Nashville recalled defenceman Greg Zanon prior to the contest following a two-game conditioning assignment with Milwaukee of the AHL.