Close to the Schumanns and admired by Mendelssohn and Wagner, Theodor Kirchner (1823-1903) was a celebrated pianist, organist and composer in his own right. His particular affinity with Brahms' music and his aptitude for arranging it were widely recognised, not least by Brahms himself, and the two were close friends from their first meeting in 1865 until Brahms' death in 1897.
After the initial appearance of Brahms' string sextet Op. 18 in 1861, the publisher Simrock commissioned several versions of the work adapted for more practicable forces, including this 1883 arrangement for piano trio, which, according to Brahms, Kirchner had "executed superbly". Relieved by his approval, Kirchner told Brahms that his sextet in its new form "would be a welcome gift for trio players".
Christopher's edition, which takes into account differences between Simrock's score and often more accurate parts, includes an Introduction outlining the personal and professional relationship between Brahms and Kirchner, a full Critical Commentary, and facsimiles from both the original sextet and the trio arrangement. Christopher's edition of the sextet was published by Bärenreiter in 2011.