This record represents blue whale sound production detected from raw passive acoustic data. The Low Frequency Detection and Classification System (LFDCS) call library for blue whales was built for the data sampled at 120 Hz, and created for A, B, and AB phrases. All detections with a Mahalanobis distance of 5.0 or less were manually screened. Daily presence for blue whales was confirmed if there were three song phrases visible, including at least one true detection. Only accepting detections when three or more phrases occurred ensured our confidence in blue whale song presence. These data were recorded at SanctSound Site SB01_01 between November 12, 2018 and January 28, 2019.