Bifwynne, to answer your question. One of the most noticeable thing about the classic 3, is the plinth and the VTA tower. The motor is also 300 rpm, hence it has bigger pulley than the Classic 1. The plinth has a solid aluminum top which actually is elevated from the surrounding piano black aluminum plinth. The Classic 3 feet are also more substantial than the Classic 1. I use a dust cover, so the elevated aluminum top is welcome, because it fits into place without moving around. The plinth, which includes the integrated aluminum top is very heavy and extremely solid. Love or hate the walnut versus piano black, that is user preference, but there is no doubt the aluminum top on the Classic 3 is at a different level versus the Classic 1 synthetic top. Also fit and finish is at a different level. The combination of materials of the plinth, aluminum top, aluminum piano black surround, is extremely solid.
I only changed out the turntable, everything else, including the cartridge and my alignment method was the same. As I mentioned the noise floor, bass response, tighter bass, then all frequencies seem more musical. I speculate that the lower noise floor is a combination of the plinth, 300 rpm motor, the different coupling of the motor to the plinth and the Classic 3 feet. In my system, to give you an idea of the noise floor reduction from the Classic 1 to the Classic 3, I will use an analogy. My analogy: System on, phono section on, tonearm on arm stand. Noise floor difference is analogous from a 12:00 volume control to a less than 9:00 volume control, where 2-3:00 is pretty much max volume. What I felt was a very substantial improvement, which was immediately noticeable. I speculate the combination of the Classic 3 arm with the Classic 3 motor, Plinth and feet in combination result in the total improvement that I witnessed in my upgrade. I dont believe you will get the entire Classic 3 performance without the Plinth, especially the lower noise floor.