P. D. Q. Bach is a fictional composer invented by musical satirist "Professor" Peter Schickele. In a running gag that Schickele has used in a four-decade-long career, he performs "discovered" works of this forgotten member of the Bach family. He has recorded this music on the Vanguard and Telarc labels. Schickele's music combines parodies of musicological scholarship, the conventions of Baroque and classical music, and elements of slapstick comedy.
The name "P. D. Q." is a parody of the three-part names given to some members of the Bach family that are commonly reduced to initials, such as C. P. E., for Carl Philipp Emanuel Bach.
PDQ is an initialism for "pretty damn quick" (or the bowdlerized "pretty
darn quick") in vernacular English.
From Wikipedia