Complex sentence: After recording 30 albums for the only record label he had worked with since 1962, Campbell got up and left the main studios of Capitol never to return, although he would record three more albums with Capitol the relationship was at an end.
Split into simpler sentences: After recording 30 albums for the only record label he had worked with since 1962, Campbell got up and left the main studios of Capitol, never to return. Although he would record three more albums with Capitol, the relationship was at an end.