Micro SX-8000 II or SZ-1

Thanks for your answers and the link. Looks like the suction section is part of the motor unit in both machines, but it looks to me that the 8000 motor unit is of better built quality and the design is nicer (at least in my eyes)

If you've never seen an SZ-1 in person, or since you have probably never taken either motor apart, how can you tell? The motors may be identical, but the SZ1 motor may come in a fancier chassis to match the rest of the turntable. If you can find an SZ-1 go ahead and buy it. It will probably make you feel better. When you do, I would like a chance to buy the 8000.

The SZ-1 motor has a built-in flywheel (which helps to make the motor box 6kg heavier than the SX8k2 motor unit) which also has an air bearing, and the floating flywheel is supposed to make the drive even smoother. The flywheel, will of course, raise the overall moment of inertia a bit as well (though not by a lot).

note: I am not sure where the VK gets their moment of inertia number. 26 tons/cm2 is way too high. Given the size/weight of the platter, you'd be physically limited to about 4t/cm2 - which is still pretty good (the biggest direct drive tables were less than half that, but they had torque going for them too).

Dear T bone: You are right, the number is 3.5 tons/cm2 for both: the 8000 and the SZ-1.

regards and enjoy the music.
Raul.

The required figures are in the link provided above.

The motor / flywheel has an inertia of 5.1 x 10^-3 kg.m^2.

It turns at 750 rpm, so the inertia referred to the platter is multiplied by the square of the gearing ratio.

22.5^2 = 506.25 so the total moment of inertia = 506.25 x 5.1 x 10^-3 kg.m^2 which is 2.58 kg.m^2.

In the perfectly ridiculous unit of tonnes.cm^2 this is indeed nearly 26.