Answer by taking a quote from the following article:

Daron Vartan Malakian (Armenian: Taron/Taron Vardan Malak`ean, born July 18, 1975) is an Armenian-American singer-songwriter, multi-instrumentalist, and record producer. He is best known as the guitarist, songwriter and second vocalist of the heavy metal band System of a Down and as the lead vocalist, lead guitarist and songwriter of the band Scars on Broadway. Daron Malakian is known for his distinctive playing and is ranked 40th in Loudwire's list of Top 50 Hard Rock + Metal Guitarists Of All Time and #11 in MusicRadar's poll, The 20 Greatest Metal Guitarists Ever.

Daron Vartan Malakian was born on July 18, 1975, in Hollywood, the only child to Vartan and Zepur Malakian, ethnic Armenian immigrants originally from Iraq. Vartan Malakian is a painter, dancer, and choreographer and Zepur Malakian is a sculptor who used to instruct college-level sculpture. At a very early age, Malakian got into heavy metal music; his distant cousin played him a Kiss record when he was four years old. Malakian started listening to Van Halen, Def Leppard, Iron Maiden, Judas Priest, Motorhead and Ozzy Osbourne among others. He always wanted to play the drums, but his parents got him a guitar instead because "You can't turn the drums off." Daron first picked up a guitar at age 11, saying in an interview, "For the first year and a half, I learned how to play by ear, and did alright. After a few years I gained a reputation as being a guitar player in high school. And by 16 or 17 I actually realized it was a good songwriting instrument, and, over anything, that's what I feel like. I don't pretend to be Mr. Guitar Virtuoso." During his teens Malakian listened to thrash metal bands such as Slayer, Venom, Metallica, Pantera and Sepultura. Malakian then began listening to The Beatles and cites John Lennon as one of his biggest influences on him as a songwriter. He also cites other British Invasion bands such as The Kinks and The Who as major influences as well as folk-rock such as trio Peter, Paul and Mary and punk pioneer Iggy Pop. Daron went to Rose and Alex Pilibos Armenian School in the Los Feliz side of Hollywood, which his future bandmates Shavo Odadjian and Ontronik "Andy" Khachaturian (System of a Down's original drummer) also attended. System of a Down vocalist Serj Tankian attended the school as well, but he was many years above Malakian and the others. Malakian attended Glendale High School as a teenager. He is a lifelong fan of the Edmonton Oilers and has a large collection of Oilers-related memorabilia.  Malakian met Serj Tankian in 1993, while they both shared the same rehearsal studio in different bands. Tankian was playing keyboard for a band, and Daron was playing guitar and singing for another band. They formed a jam band called Soil with bassist Dave Hakopyan and drummer Domingo Laraino. Shavo Odadjian then became their manager, and then rhythm guitarist. Soil broke up and Malakian, Tankian, and Odadjian (who switched to bass) formed a new band using the name "System of a Down", based on a poem that Daron wrote. The poem's title was "Victims of a Down" but Odadjian thought "system" was a stronger word than "victims." They then recruited drummer Andy Khachaturian, who was replaced by John Dolmayan in 1997.  Malakian co-produced System of a Down's albums with Rick Rubin, as well as albums by The Ambulance and Bad Acid Trip (a band on fellow member Serj Tankian's Serjical Strike Records). In 2003, Malakian started his own label, EatUrMusic, on which Amen was the first signed band. The label is now inactive and its current status is unknown.

What year did they immigrate to the US?
on July 18, 1975, in Hollywood,