He is a guitarist and founding member of the nu metal band Korn[3] and his solo project Love and Death, where he also provides vocals.

Along with fellow Korn guitarist James "Munky" Shaffer, Welch helped develop Korn's distinctive sound (a mix of sirenlike shards of dissonant guitar that mimicked a turntablist's various effects and rumbling down-tuned riffing) that defined the nu metal aesthetic beginning in the mid-'90s.

He reunited with Korn on-stage at the Carolina Rebellion in May 2012 for the first time in seven years;[4] Welch officially announced in May 2013 that he was rejoining the band.

Musicians Reginald Arvizu, James Shaffer, and David Silveria wanted to continue, and they hired Welch to play guitar in their new band named "Creep".

[3] According to Welch, the band members also suffered personal battles with addiction: "We were only sober for just a couple of hours a day in Korn.

You try to just be at peace but even a big, huge band like Korn, playing in front of thousands of people, it can get lonely.

[17][18] He has declared that he has rid himself of all drugs in his "own personal rehab" with God, in which he had checked into a hotel room and sat in his bed for hours.

[19] In July 2005, Welch appeared on CNN's feature-format program "People in the News", where he admitted to having been addicted to alcohol, methamphetamine, Xanax, and sleeping pills[20] before being introduced to the Christian faith.

In a podcast with Headbanger's Blog, on May 30, 2008, Korn vocalist Jonathan Davis expressed interest in playing with Welch on the band's upcoming album, but stated that it is not likely.

[21] In late 2008, Welch, among other celebrities such as Josh Hamilton and Greg Ellis, appeared in testimonial videos called I Am Second in which he shares his story of recovering from drug use with the help of his faith in Jesus Christ.

[22][23] In September 2009, Korn guitarist Munky, in an interview with Altitude TV, alleged that the band had denied a request by Welch to rejoin the outfit.

[24] Shortly after, Welch responded to the statement via his Myspace and official website, denying the claims: I recently learned of an interview that Munky gave where he said that I came to Korn and asked to be taken back in the band.

'[25] Welch told Alternative Press magazine that it was at this time that he had essentially become broke because of bad business deals, mismanagement, and philanthropy.

Welch stated there was a time that he was unable to pay his bills and resorted to finding loose change around his rental home to cover essentials.

[26] On June 17, 2011, Welch had a private interview, shot by Carson Bankord of Red Rocks Church in Golden, Colorado, in which he discussed his conversion experience.

[39] A number of demos from these early sessions surfaced on peer-to-peer networks, among them "A Cheap Name", a song directed at rapper 50 Cent.

In his autobiography, Welch mentions the songs "Washed by Blood," "Save Me from Myself," and "Rebel", which all have made the final track listing for the album.

[40] During his stay in Israel with members of the Valley Bible Fellowship of Bakersfield, California, Welch continued to write songs for his solo effort, confident that the music would speak for itself.

[41] On March 15, 2008, Welch announced he had founded a record company with Mark Nawara and Greg Shanabeger called Driven Music Group.

For the album, Welch contributed the majority of the instruments, but also hired other contributors, including rhythm guitarist Archie J. Muise Jr., bassist Tony Levin, and drummer Josh Freese, for assistance.

The first single, Flush, was released on July 5, 2008, at Cornerstone Festival in Bushnell, Illinois, and a music video directed by Frankie Nasso followed on September 5.

The group includes musicians in other alternative/nu metal bands such as Lacey Mosely of Flyleaf, as well as freestyle motocross athlete, Ronnie Faisst.

[48] Sandoval and Ries speak publicly worldwide in settings such as schools, rehab centers, parks, conferences and youth events inspiring individuals who are eager to discover their purpose.

[57] On March 22, 2011, Welch got into a legal battle with his own label, Driven Music Group, and former managers Greg Shanaberger and Mark Nawara.

Welch also claims that Shanaberger attempted to hide "his fraudulent, unethical and illegal behavior"[58] by listing his then fiancée as a shareholder.

On May 17, 2016, Love and Death released a new single, "Lo Lamento", as a free-download with the purchase of his book, With My Eyes Wide Open: Miracles & Mistakes on My Way Back to KoRn.

[61] Welch was among the live lineup for metal worship project HolyName, a group led by former Sleeping Giant frontman Tommy Green.

On December 6, 2023, Welch unveiled a new record label he created with longtime manager David Williams, and announced Christian Rock band Spoken as his first signees.

[64] Welch's first guitar was a Peavey Mystic, which he later sold along with a practice amp to future bandmate James "Munky" Shaffer.

[65][66] Since leaving Korn, Welch mostly uses custom-built baritone guitars from Ibanez, making use of the RG and, at the time, newly introduced RGD shape.