Downton Abbey composer John Lunn and saxophonist Jess Gillam join Cerys Matthews and Jeffrey Boakye on a journey from the snowy landscape of northern Finland to the warmth of Ecuador as they add the next five tracks, exploring unusual instruments and effects, including the theremin and the tremolo.

Guitarist and songwriter Johnny Marr, formerly of The Smiths, talks us through one of the most ambitious uses of tremolo, and guitarist Adam Goldsmith demonstrates a few other tricks guitarists have up their sleeve.

This episode was first broadcast in March this year.

Producer Jerome Weatherald

The five tracks in this week's playlist:

Kilisee, Kilisee Kulkunen by Tapiola Choir

Other music in this episode:

(Love is Like a) Heatwave by Martha & the Vandellas