Chart datum, level of water depth on a nautical chart. Datum or datum point, a (possibly arbitrary) reference baseline or point from which scientific measurements are made (from a Latin meaning of datum as a given, i.e. an accepted fact)
Music directors and composers must guide musicians and singers by preparing musical arrangements and helping them achieve the best possible sound. Musical talent. To become a music director or composer, one must have musical talent.
Two years extra spent on a Masters degree in music might not help someone applying for an Electrical Engineering position, while a 3-year MSEE from Purdue, MIT or such might be extremely useful in the New Product Design group.