Where was Metallica's 1991 self-titled album, commonly called The Black Album, primarily recorded?

Metallica's 1991 self-titled album, commonly called The Black Album, was primarily recorded at One on One Recording Studios in Los Angeles.

The sessions began in October 1990 at the North Hollywood facility, which was also commonly described as being in Los Angeles. The band recorded there during an eight-month period that ended in June 1991. A short period of work also took place at Little Mountain Sound Studios in Vancouver, while additional overdubs and mixing were completed at A&M Studios in Hollywood.

The One on One sessions were important because producer Bob Rock wanted the members to perform more collaboratively. Earlier Metallica recordings had often been assembled from individually recorded parts, but Rock encouraged a more live, band-oriented approach. This contributed to the album's tighter and more immediate sound.

The studio is sometimes confused with the other facilities used for overdubs and mixing. One on One was the principal recording location, while Little Mountain and A&M handled additional work. The demanding sessions were later documented in the film A Year and a Half in the Life of Metallica.