Bar (unit) The kilobar, equivalent to 100 MPa, is commonly used in geological systems, particularly in experimental petrology. "Bar(a)" and "bara" are sometimes used to indicate absolute pressures and "bar(g)" and "barg" for gauge pressures. This usage is deprecated and fuller descriptions such as "gauge pressure of 2 bar" or "2-bar gauge" are recommended. Bar (unit) The bar is a metric unit of pressure, but is not approved as part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa, which is slightly less than the current average atmospheric pressure on Earth at sea level. The
Sixteen-bar blues Sixteen-bar blues The sixteen-bar blues can be a variation on the standard twelve-bar blues or on the less common eight-bar blues. Sixteen-bar blues is also used commonly in ragtime music. Most sixteen bar blues are adapted from a standard twelve-bar progression. The standard twelve-bar blues progression is where each cell in the table represents one measure (or "bar"), "I" represents the tonic chord, "IV" the subdominant chord, and "V" the dominant chord. Twelve-bar progressions are formed by applying one of several formulae, including the following. One adaptation extends the first section of tonic chords (bars 1–4) by doubling or repeating