The German “tenor horn” is a tenor-voiced instrument in Bb covering the same range as the euphonium and trombone. Not to be confused with the modern British tenor horn which is in use in the brass band and pitched in Eb. The brass band equivalent would be what we call a baritone, though the tenor horn that Mahler calls for is somewhere between the British baritone and euphonium in sound quality (though all share the same length of tubing and tessitura).

Nitzan Haroz (who is the principal trombone of the Philadelphia Orchestra) played the part on a euphonium, though also contributed later in the evening on trombone (which I presume led to the listing as simply “Brass”). The sound he produced on the euphonium was remarkably similar to that of the German tenor horn, or a true tenor tuba, rather than a modern brass band euphonium sound.

Leni Maeckle is a bassoonist. The Eb Clarinet was played by David McGregor