The Chicago Symphony Orchestra is one of the world’s greatest. Its modern status was largely achieved by the Hungarian Fritz Reiner, the orchestra’s music director from 1953 to 1963, whose legacy can still be heard in the ensemble’s virtuosity and power. In 1969, Georg Solti—another Hungarian conductor who demanded the highest standards—began his 22-year reign at the orchestra’s helm and gave us a vast treasury of recordings. His Mahler cycle typifies his very particular approach—dramatic, often forceful, though capable of moments of genuine lyricism (the Second and Fifth symphonies are perfect examples of that approach). Among the nine complete symphonies (he doesn’t give us the unfinished Tenth Symphony), the 1971 recording of Symphony No. 8 (the “Symphony of a Thousand’’) is a true classic. Recorded in Vienna while the orchestra was on tour, this Eighth has a spectacular lineup of vocalists, with the glorious Lucia Popp soaring over the vast forces. Elsewhere (as in No. 1 and No. 4), Solti and his Chicago bring ample expression and atmosphere to Mahler’s iconic works.