Martyn Jerel Buchwald was born on January 30, 1942, in Cincinnati, Ohio. He was raised in the San Francisco Bay area, though, and attended college there. He started out as a painter, but appeared in a production of West Side Story, and after that continued as a musician. He released a few solo singles, worked in folk groups, and in 1965 met up with Paul Kantner and the two formed the Jefferson Airplane.

Balin was the chief songwriter as well as one of the main singers, and once the band became big with Grace Slick becoming the focus of media attention, Slick and Balin started to become rivals. Jorma Kaukonen and Jack Casady also criticized his style of writing, which was relatively normal compared to a lot of the more psychedelic, rock, and blues things the band was doing. Balin stayed with the band a few years, but then quit at the end of 1970.

After that, Balin worked with several groups, and when he and Kantner made up enough for Balin to guest on Kantner's solo projects, Balin came back to the band that was now called Jefferson Starship. His song "Miracles" on their 1975 Red Octopus album was the biggest hit they'd had in a long time. But again, he felt underappreciated, and left in 1978. He wrote and performed the rock opera Rock Justice, which wasn't much of a success, but then released a solo album, Hearts, which contained mostly ballads. It was fairly successful but its follow-up album wasn't.

In 1985, Balin worked with his ex-bandmates in the KBC Band (Kantner, Balin, Casady). After a few years in that, they all participated in the 1989 Jefferson Airplane reunion album and tour. The reunion didn't last long, though, and Balin did another solo album in 1991 before rejoining Kantner in "Jefferson Starship -- The Next Generation." He continued to do occasional solo albums after that as well as going back to painting.

In 2016, Balin had open-heart surgery in New York City, and later sued the hospital for malpractice, saying a tracheotomy had paralyzed a vocal chord and led to the loss of part of his tongue, and also that a hand injury suffered in the hospital led to his left thumb being amputated. He died on September 27, 2018, and his widow Susan added a wrongful death claim to the suit. (However, she dropped the suit in 2020 due to inability to meet court deadlines after the original lawyer withdrew from the case.)

Sources:
http://www.britannica.com/psychedelic/textonly/jeffersonairplane.html
http://www.starship.pp.se/bio/marty_balin.html
http://www.allmusic.com/cg/amg.dll?p=amg&sql=B2zsqoa9abijb~C
https://www.washingtonpost.com/local/obituaries/marty-balin-founder-of-1960s-group-jefferson-airplane-dies-at-76/2018/09/29/3a0db264-c3ee-11e8-97a5-ab1e46bb3bc7_story.html
https://completemusicupdate.com/article/widow-of-jefferson-airplanes-marty-balin-drops-medical-malpractice-lawsuit/