Mwaller, I don't hear any distortion on my copy as played here. Two thoughts:
1) have you cleaned the record with Disc Doctor, AIVS, Walker Prelude or comparable cleaing fluids? (I've found this can make a difference on many of the RTI pressings.)
2) it may be cartridge alignment, tracking force or VTA not being high enough, as you suggest. Do you have other large orchestral 180-200 gram LPs to compare against?
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