Led Zeppelin II was released today in 1969. It began with rehearsals at my home in Pangbourne and 'Whole Lotta Love' and 'What Is and What Should Never Be' were later recorded at London's Olympic Studio Number 1 with George Chkiantz, who engineered the basic tracks and some guitar overdubs. This provided the foundation for the rest of the tracks to be recorded and overdubbed at various studios in America during our forthcoming tour. We recorded and overdubbed our way from West Coast to East Coast with tour-fuelled energy. I did the final mixes with Eddie Kramer at A&R studios in New York. The hedonistic mix of 'Whole Lotta Love' was to pioneer the radio success of the album.