Did you see the size of that tam-tam!?! - more on that in a minute. From a purely technical standpoint, Maazel is the greatest conductor on the planet (I said technical, not musical). There's a reason why orchestras just love this guy. Watch how he just sits on the last note before the chorus cuts out; just waiting for the bass drum to finish making its huge crescendo. That's exactly how I would conduct that spot. He took the orchestral postlude much slower than he did on his commercial recording. By the way, just type "Mahler Maazel" in the search line at youtube.com, and all of the parts will come up.
Anyway, it's a typical ORF (Austrian Radio) recording - the offstage brass don't get captured very well, for example. The orchestra is clearly the Vienna Philharmonic (you can tell from the indiginous Wiener single F horns), but it's from neither of the two symphony halls in Vienna. I suspect that this must have been a Salzburg Festival performance, especially since the organ sounds like it might be a portable electronic one. Now about the percussion . . .
That Wuhan tam-tam is at least 130 cm. (50 inches). Those tam-tam strokes were deep and profound sounding - as they should be. I've also never before witnessed the VPO using such large mallets on a bass drum like that. That's always been one of my biggest complaints about the VPO percussion section: they use small, antiquated bass drum mallets (but not here). I wonder if Maazel might have had Pittsburgh's 130cm. Wuhan flown over? I know that the VPO owns a 100 cm one, but this one is clearly larger than that. Anyway, watch for the gong! Believe me, you'll hear it too.
http://www.youtube.com/watch?v=FX62TyprDm8Julia Varady / Angela Maria Blasi / Juliane Banse / Marjana Lipovsek / Margarita-Hintermeier / Johan Botha / Monte Pederson / Jan-Hendrick Rootering / Konzertvereingung / Wienerstaatopernchor / Chor des Bayerischen Rundfunks / Rias Kammerchor / Wiener Sängerknaben / Wiener Philharmoniker / Lorin Maazel, conductor