Let me offer the argument for tremolos: Barry is correct, the notation is actually 32nds, but any note with three strokes through its tail (or above or below in the case of whole notes) can also be played tremolo. It's just one of the great ambiguities of musical notation. It's a huge problem in timpani parts. In the Viennese classical tradition, as H.C. Robbons Landon and others have shown, even a single line can be interpreted as a tremolo and was clearly meant to be played that way though it seldom is now (for example, the timpani part at "and there was light!" in The Creation). In string parts where there might be an issue, composers often write the word "tremolo," but then just as often they don't. Some, like Berlioz and Tchaikovsky, use more than three strokes when they want tremolos, particularly in slow tempos, but the "3=tremolo" convention is very old.
For example, Mahler does write "trem." at the beginning of the Second Symphony, but he does not at the beginning of the finale or for the strings at the final reprise of the great chorale at the end--and the notation is exactly the same. But the most telling notational evidence comes from that king of the tremolo, Bruckner. He often declines to write "trem," and never uses more than three strokes over a note, and yet almost everyone plays his string parts notated that way as tremolos. Imagine the openings of the last three symphonies played as distinct 32nds in the strings! The actual performance tradition, never mind the sound of the music, requires tremolos. One person who does not follow this convention is Kubelik in those loud, "cosmic void" fanfares in the Adagio of the Ninth (on Audite), and the result is so strange sounding that it's quite startling.
So the evidence of the score at the beginning of Mahler's Seventh strikes me as very ambiguous. Yes, it's possible to play distinct 32nd notes, but the presence of simultaneous rolls on the bass drum, and tremolos in the clarinets, suggests to me that this is incorrect. I think we are dealing here with one of those stylistic conventions that Mahler did not feel the need to notate precisely because it was universally understood. If he wanted 32nds, he might have done what many composers do--write dots (.....) over the half notes to indicate that they should be clearly articulated. So it's not correct to say that tremolos are wrong, citing the score as evidence. Personally, I prefer tremolos--I think it sounds more mysterious, atmospheric, and the rhythms come off as less four-square.
Dave H
