Jeremy Eichler's new book, Time's Echo, just out from Faber (HB; £25) tangles with memory – what we choose to remember, what to forget – as history takes hold, and he argues that music can become in many ways the most powerful form of memorial. To illustrate this argument, he engages with works by Richard Strauss, Arnold Schoenberg, Dmitri Shostakovich and Benjamin Britten. James Jolly caught up with him recently to talk about the book.  The musical excerpts which appear on the podcast, with kind permission, are: Shostakovich Symphony No 13, 'Babi Yar' Nikita Storojev; CBSO & Choir / Okko Kamu (Chandos) Schoenberg A Survivor or from Warsaw Franz Mazura; CBSO & Chorus / Simon Rattle (Warner Classics) R Strauss Metamorphosen Sinfonia of London / John Wilson (Chandos) Britten War Requiem Soloists; Choristers of St Paul's Cathedral; LSO & Chorus / Richard Hickox (Chandos)