At 18 he played principal horn in the London Symphony Orchestra for a short time.

Moving to London, he played as principal horn with many orchestras and chamber groups.

Brain filled the position as principal horn in both.

The order from the principal horn (1st horn) to the 4th horn is right to left from the director's view.

Much of the horn repertoire is scored as featured parts for the orchestral players, especially the principal horn.

In 1982 he joined the Chamber Orchestra of Europe as principal horn.

He was also principal horn of the Kansas City Philharmonic.

He was principal horn of Sir Thomas Beecham's opera company orchestra in 1913.

He was later principal horn of the Seattle Symphony Orchestra.

His tenure as principal horn in Seattle began in 1996 and ended in 2011.