Hey, wait a damn' minute! I WAS being unpleasant! Oh, well, never mind...
I think #1145 really summed it up when he observed that the classic 3-violins is "that sound" as that's exactly the way it seems to affect people. Tidily succinct, Mr. Thompson.
With the amount of time I spend trying to recreate authentic-sounding Mellotron patches on my trusty Korg X5D's, I've noticed that the out-of-tune-ness of the 3-violin sound, (which I intuit as an artifact of the minor intonation difficulties of three humans trying to play perfectly in tune with each other for eight seconds with little external pitch reference and probably little musical context to play the intonations exactly right every time,) is almost impossible to reproduce from note to note, but it is possible to create a sound that works similarly when sitting in a mix. You can hear that the original was recorded "on the fly" with probably an idea of "let's at least get this prototype to work - we can worry about getting the sounds just right later" and the results were sort of "good enough for now". Let's face it, humans get bored, ears get tired, and it's clear that the recording was done in less than ideal circumstances. Nevertheless, the sound has in incredible weight and density that carves its own place in a mix, and it's hard to envision any other sound that will carry exactly the same sensation with it.
That said, I am eager to listen to the 21st century Mellotron strings. I hope that it does have a lot of similar weight and emotion when compared to the original, and I'm sure it will be a wonderful and useful sound, no matter what. Will it ever affect people the same? Only time will tell. I suspect our descendants on the list will be debating that exact point hotly in another fifty years.
It's funny, I'm not a fidelity freak on my own time. Usually, when I perform, my instructions to the sound man are "make the piano patches sound as good as possible and I'm happy!" I figure that everything else will follow, as long as my piano patches are GRAND sounding. So, perhaps I'm not the best person to be on a soapbox here, as I don't look for exact recreations of sounds, I just look for sounds that are good.
Finally, what's "Brummy?"