These recordings are with two different orchestras (Mahler 1st with the Chicago Symphony and the 8th with the London Philharmonic). Tennstedt's live performances are much better than his studio versions of the same works, and it's wonderful to watch him coaxing what he wants from the players. Even though he conducts from the score rather than from memory, he always seems to be directly connected to the orchestra in an almost magical way. The sound is good in both performances, and there is a sense, on both occasions, of being present for something quite special. These are great performances.