Another technically ignorant question needing an answer. I IMAGINE that because Record decks, arms, cartridges and speakers contain mechanical components subject to stres, resonance etc, we have good reason for suspecting that all these (unless designed and made to an identical spec) WILL sound different to each other and further, that good engineering can produce 'better' (SIGH OK, closer to mastertape in replay....accurate if you must) sound. Am I therefore correct in assuming that it is NOT just a matter of time before someone starts a 'do all record decks sound the same' thread?
Please just say yes, so I can sleep at night
There are lots of factors that affect the sound of vinyl replay. The quality and performance of the cartridge, stylus geometry etc have a significant effect. As you suggest, the resonances in the arm , tightness or slackness of bearings etc will also affect the sound, although in my experience these are becoming secondary effects.
What makes the least difference I've found is the turntable itself. There is some difference, especially when it comes to isolation and microphony, so is dependant on mounting and positioning relative to the loudspeakers, walls etc. However, if you listen on headphones so there's no loudspeaker playing, and don't have kids running about bouncing a suspended floor, I suggest you won't hear any difference between turntables with identical arms and cartridges as long as the turntables go round at the right speed and with minimal rumble and wow&flutter.
However, in normal use, when the turntable as a system is played in the audio field from the loudspeakers, yes there will be a difference which will still show up in blind tests due to all the above reasons.
Turntables are about the only thing left worth playing with.......