It is interesting to note that Johnny Cash’s voice does not seem to appear on any of the released tracks. Since his voice is not obvious on the tracks, the point at which Cash arrived at the studio has been a matter of discussion. Carl Perkins and others have stated that Cash was already at the studios when Presley arrived, with Perkins adding that Cash had stopped into the studios to “get some money”. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.