By 1958, Liberty was close to bankruptcy when singer-songwriter Ross Bagdasarian, performing as David Seville, had a number one hit with his novelty song "Witch Doctor". Later that year, he combined multi-track recording with the altered speed technique he had used in "Witch Doctor" and introduced the Chipmunks (Alvin, Simon, and Theodore) in "The Chipmunk Song (Christmas Don't Be Late)". The Chipmunks were named after Liberty executives Bennett, Waronker, and Keep, respectively.) In the months leading to Christmas of 1958, the record went to number one on the "Billboard" Hot 100, becoming the first Christmas record to reach number 1 on that chart and selling 4.5 million copies.