John Valby (born 1945 in Rochester, New York) is a musician and comedian who plays in barrooms and college campuses across the east coast. Using an old-fashioned piano, he creates comedic parodies of classic songs. He can always be found performing in his classic white tails tuxedo and black derby hat.

Valby lives up to his nickname "Dr. Dirty". His songs and shows focus mainly on sex and racial slurs, with a mix of current and historic people and events. However, his routine shows no favor and spares no target in pursuit of making his audiences laugh. From Hispanics to Irishmen, Polish to blacks, Arabs to rednecks, Republican and Democrats alike, no person and no group is safe from his jokes and his piano.

Many of the songs sung by Valby are drinking songs like Ya, Ya, Ya (aka Limericks), Roll Your Leg Over, Barnacle Bill, etc. See Richard Reuss' master thesis and Ed Cray's Erotic Muse for further examples.

While Valby is best known for his "Dr. Dirty" act, he has recorded and produced pop and rock albums for himself and other artists. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.