Gustav Mahler was not as revolutionary harmonically as many people seem to think – he followed a rather logical evolutionary trail blazed by his beloved Wagner and his mentor Bruckner – but his innovations were instrumental in turning the symphonic form into something deeply personal. Mahler plunged boldly into the inner space of mind and personality previously unexplored. He was as far from Brahmsian detachment as it was possible to be in fin-de-siecle Vienna.

Those of us who adore his music point out the disarmingly intimate emotional spectrum laid bare before our ears as testament to the composer’s profound humanity. But opponents feel justified in presenting this same brave exposure as maudlin and banal. Back in the early 1960s,when Leonard Bernstein was capturing a wider audience for Mahler’s amazing body of work, many of my friends and colleagues dismissed these long psychodramas as “movie music.”

The Philadelphia Orchestra must be the last major ensemble in America never to have performed a cycle of Mahler symphonies. The orchestra’s musical director, Christoph Eschenbach, is remedying this oversight, and continued his traversal with the harrowing No. 6 on Tuesday evening at Carnegie Hall. You have to admire Mr. Eschenbach’s focus and courage, especially since his first few attempts at Mahler were woefully deficient.

Like Simon Rattle in Berlin and James Levine in Boston, Mr. Eschenbach has the urge to tinker with the sound of his ensemble. His latest innovation is a repositioning of the strings, with the second violins moving to the antiphonal position directly on his right. Despite all the interpretive problems he has manifested thus far in Philadelphia – such as a shameless milking of the “I’ll Be Seeing You” theme from Mahler’s Third Symphony that would have made even Liberace blush – I have not heard any deterioration in that “fabulous Philadelphia” sound. But Stokowski giveth and Stokowski taketh away.

In creating such a beautifully blended string sound, the orchestra has sacrificed the intonation and dynamics of the rest of the group.What I like to call “the great wall of strings” keeps the wind and brass players from being able to perform at their normal decibel levels. Since the orchestra very rarely employs risers, the non-string players are anonymous, unseen, and desperate to be heard.

Except for the horns, who glided magically along with their stringed mates Tuesday night, the rest of the band, particularly the clarinets and the trumpets, sounded shrill. And I wondered why the bassoon players even got on the bus to come up to New York for the evening.

Mr. Eschenbach did a good job by simply enforcing discipline on the one member of the orchestra who really needs it – himself. He made a nice recovery after beginning with a misstep. The opening tempo was much too fast – not too fast for Mahler, but too ambitious for this particular ensemble on this particular night – and Mr. Eschenbach knew it. He reneged as soon as possible and reprised the original thematic material at a much slower speed. One excellent effect was having the sound of Mahler’s beloved herdenglocke – the cowbells – emanate from the back of the hall. The passages for strings alone were above reproach.

I wholeheartedly agree with Mr. Eschenbach’s decision to perform the Scherzo as the second movement. Many conductors play it third, offering the lovely Andante moderato in the second slot. Mahler himself experimented with both methods (hence the latitude for leaders). But, for me, this symphony is all about relentlessness: We should not have a break after the Tartarean first movement, but more demonic tension.

Restored to its proper place, the Andante was truly beautiful. Largely strings and achingly lush, this is meat and potatoes for the orchestra of Ormandy, which offered a masterly performance. The cowbells were now placed on the stage (nice touch). Even the winds had their chance to shine: In a subtle dab of Mahlerian color almost always missed in performance, Mr. Eschenbach allowed the solo flute to linger at the end of the movement after all others had finished.The finale was a bit unfocused, but that is primarily the doing of Mahler himself.

Overall, this was a credible reading. If Maestro Eschenbach’s band continues to progress at this rate, it will be able to offer by the 10th concert (not the 10th symphony, since they have already performed that one) the type of superior evening we had come to expect from the Philadelphia Orchestra.

About five years ago, I heard the Dresden Staatskappelle perform the Mahler Sixth up the street at Avery Fisher, led by a robust and vibrant Giuseppe Sinopoli. Maestro Sinopoli is no longer with us, and I thought of him often during this performance. Remembering this extinguished firebrand reinforced Mahler’s thesis that whatever else may distract us along the way, the human condition is ultimately tragic.