In 1967 the LPO appointed Bernard Haitink as its principal conductor. He remained with the orchestra for twelve years, to date (2018) the longest tenure of the post. His concerts made a strong impression with the public, and within months the LPO was playing to ninety per cent capacity audiences at the Festival Hall, far outstripping the other London orchestras. Among the composers with whom Haitink was associated were Bruckner and Mahler, whose symphonies featured frequently in the LPO's concerts during the Haitink period, as did those of Shostakovich, particularly the Tenth, which Pirouet describes as the calling card of the orchestra and conductor. With Vladimir Ashkenazy, Haitink and the LPO gave a six-concert cycle of the Beethoven symphonies and piano concertos, for which the Festival Hall was full to capacity. In "The Times", Joan Chissell described the orchestra's playing as "worthy of any festival". There was some discontent within the LPO that Haitink's prolific recordings were almost always with the other orchestra of which he was the chief conductor, the Amsterdam Concertgebouw. Pirouet comments that as Haitink recorded exclusively for the Dutch firm Philips it was to be expected that the Amsterdam orchestra would be preferred, and in any case the LPO was recording extensively with Boult, Solti, Daniel Barenboim and many others. In the 1970s international tours continued, with itineraries taking in the US, Western Europe, the Soviet Union, and, in 1972, China, long inaccessible to Western musicians, where the orchestra met an enthusiastic welcome.