but the physical object is nothing without an electromagnetic cartridge to convert the info in the grooves into voltage.
...just to be a nitpicker: tape heads are electromagnetic; turntable cartridges are electromechanical, using a piezoelectric system. You can spin a record with the power off, and if the needle is in the groove, you will hear sound off the cartridge.
In regards to vinyl sound versus CD, it's unfortunate that so many uninformed and incorrect myths persist about which format is "better." It's apples and oranges as each format requires its own set of mastering techniques, which means that identical recordings end up being different depending on the format.
I never really fooled with vinyl much until buying the Pearl Jam limited edition set, which has material only available on vinyl for my wife, and had to add a turntable and preamp to my stereo setup, which is far from being audiophile approved (though I'll wager mine's better than most "audiophile" setups.) Records DO sound different, and after scavenging through thrift stores just picking up whatever interested me, I ended up with some stuff that duplicates my CD collection. On several tracks, there is no contest; the vinyl tracks are more dynamic, and just plain sound
better, but IMO, it's because the subsequent CD releases were mastered by engineers who had much less understanding about what they were doing and not the format itself.
Being a crusty old engineer myself, I tend to chalk it up to the 'kids don't know what to do with it, but ain't that new toy shiny' in regards to uncompressed digital audio. All it takes is a listen to some early 80's CD's that were mastered on BASF 1630 digital videotape to hear that.