Weldon Jonathan Irvine, Jr. (October 27, 1943 – April 9, 2002), also known Master Wel, was an American composer, playwright, poet, pianist, organist, and keyboardist.
Irvine, an African American, was born in Hampton, Virginia on October 27, 1943. He moved to New York City in 1965. He was involved with various musical genres including Jazz-Funk, jazz, hip hop, funk, rhythm and blues, and gospel. He served as the bandleader for jazz singer Nina Simone and was a mentor to many New York hip-hop artists, including Q-Tip and Mos Def. He wrote over 500 songs, including the lyrics for "To Be Young, Gifted, and Black", performed live for the first time by Simone on the album Black Gold (1970). It has been dubbed the "official" Civil Rights anthem.
In 1999, Irvine contributed on Mos Def's debut solo album Black On Both Sides. Irvine's last major project was The Price of Freedom (1999), a compilation of original songs by hip-hop, jazz, funk, and R&B artists to respond to the shooting of Amadou Diallo. In 2000, Irvine provided the vocal introductions to tracks on the first CD of the album  by UK Drum & Bass producer Big Bud. He co-wrote and performed vocals and played the Fender Rhodes on the first track entitled Return of Spiritman. He also played the Fender Rhodes on closing track Persian Blues.
- 1972: Liberated Brother (Nodlew)
- 1973: Time Capsule (Nodlew)
- 1974: In Harmony (Strata-East)
- 1974: Cosmic Vortex - Justice Divine (RCA Records)
- 1975: Spirit Man (RCA Records)
- 1976: Sinbad (RCA Records)
- 1979: The Sisters (Saucerman)
- 1994: Music Is the Key (Luv N Haight)
- 1995: Keyboards Wild DJ's Smile (Tuff City Records)
- 1998: Embrace the Positive (Nodlew)
- 2000: The Amadou Project: The Price of Freedom (Nodlew)
straight life (freddie hubbard, 1971- tabla, tambourine)
- Comin' on Home (Blue Note, 1971)
With Big Bud
- Late Night Blues (Good Looking Records, 2000)
- Earth Volume 5 (Track: Amigo Mio) (Good Looking Records, 2001)
- "Weldon Irvine". Nathaniel Turner. Retrieved 2006-12-15.
- "Weldon Irvine: Biography". allmusic.com. Retrieved 2006-12-15.
- "Weldon Irvine". artistdirect.com. Retrieved 2006-12-15.
- "Mos Def - Black On Both Sides (Vinyl, LP, Album)". Discogs. Retrieved 2015-12-28.
- "Big Bud - Late Night Blues (CD, Album)". Discogs. Retrieved 2015-12-28.
- "Music and Suicide: A Tragic History". BET. Retrieved 10 July 2015.
- Nikhil Yerwadekar. "Yesterday's New Quintet". Hip Hop Site. Archived from the original on January 16, 2016. Retrieved 2006-12-15.