The SoundBar 2 Digital Bar Checker offers a convenient, quick and safe method of obtaining sound velocity data for calibration of echosounders and other acoustic devices. Developed from the acclaimed miniSVS sound velocity sensor, the SoundBar 2 uses a digital time of flight technique that gives the most accurate sound velcoity data in the world. Coupled to a pressure sensor in a durable titanium housing, the SoundBar 2 is lowered through the water column, measuring the sound velocity as it goes. The display unit records this data and presents the mean sound velocity value over the profile, which may then be output in a variety of industry standard formats to the echosounder.