What musical instruments feature at the beginning of the Main Theme in Foyle's War?

I hear English horn, bassoon, Flute, Clarinet, and strings.

The first answer given was "Oboe and bass for the first four bars, then oboe with clarinet and strings, then flute with oboe, bass and strings."

I think it is possible, even highly likely, that it is not an oboe but an English Horn. The tone quality sounds much more deeply resonant than would be expected for an oboe, especially in the lower register.