fair enough, they did though use elctric guitars and keyboards in the
studio as far as I can tell. My point is actually about frequency band
overlaps and phase shifts as a result of crossovers and electronic
enhancements in the transmission chain,, both on recordings and
playback. Most studios don’t even care about absolute polarity much, a
significant number of recordings are out of polarity and you hear it on a
good system.
Guitar amps don't have crossovers. Guitarists are incredibly picky about their 'sound' and go to great lengths to get exactly what they want- which is a combination of effect pedals, the amplifier and its volume and tone settings (and tubes), and finally a speaker deemed appropriate, not to mention the actual guitar and whatever pickup and other mods it might have.
Being a keyboard player, I know how important it is to have clean sound so my keys go directly into the mixer without any speakers involved- that's how most of them do it. The exception is something like a piano or Fender Rhodes that is either directly miked or has to be played through an amp to get the 'sound' at which point the mic is in front of the speaker.
You are correct about polarity, this is true of all recordings which is why a switch to invert polarity can be nice on the playback preamp, since 50% of recordings are inverted polarity. That's hard to hear if the recording is multi-miked though, which includes a fair amount of classical recordings (most of which I don't regard as 'reference').
@mozartfan I've been playing around a lot with 'full range' drivers over the last 20 years. If they do alright with classical they do alright with rock and anything else too. FWIW there's plenty of information coming from an orchestra below 60Hz!! I played string bass in orchestras for decades- low E is 41 Hz. Bass drums can be in the low 20s, organ pedal tones can go to 16 Hz (32 foot pipes). When I recorded Canto General I insisted to the producer that she arrange for the largest bass drum in the state, which was a good 5' in diameter. Its simply not something you can experience on a 'full range' driver :) When played back properly on a good system, that drum shakes the walls, which is what its supposed to do.