Hi birdman,
I think it's likely both factors. Vinyl typically has higher frequencies like brushed cymbals somewhat rolled off. On average, highs between 10 kHz and 20 kHz on vinyl are about -3 dB below those of the same tape mastered to CD, except for some of the direct-to-disc and 45-rpm mastered LPs like The Sheffield Drum Record, which first on vinyl and then reissued on CD remains the best recording of a drum kit ever made.
Mastering engineers for vinyl routinely would tweak the high frequencies (roll them off a bit) so cheap phono cartridges would track them without distortion.
By the way, CD is not a "lossy" algorithm like MP3. The Nyquist theorem demonstrates that a digital sampling of a 20-kHz frequency--so long as you use a 44-kHz sampling frequency, which CD does--will perfectly reconstruct the 20-kHz frequency. On instant A/B comparisons of the half-speed mastered vinyl of the Sheffield Drum record vs. the CD reissue, both running in sync., apart from occasionally audible LP surface noise, I'd challenge anyone to be able to tell them apart. (I used to set up comparisons like this when CDs were first introduced in the early '80s.)
Of course, there are huge differences introduced by tweaks in EQ on a CD remaster. Some are really awful; others improve on the original. I have three different vinyl issues of a classic jazz vocal album by Lambert, Hendricks & Ross, one pressed in Italy that's really nice, plus a couple of CD reissues. Some of them are very different in tonal balance, even the vinyl. The best-sounding ones are the Italian vinyl pressing and an American CD digital re-mastering of a few years ago. There was an American vinyl re-issue in the 1980s where the vocals had a lot of midrange treble emphasis that makes the LP all but unlistenable.
Regards,
