Davide256: "the belt provides isolation in power transfer. But a platter mounted on same sub chassis as motor still sees vibration transfer through the chassis. Rega follows this model."
The Sota Cosmos (couple models higher than your Sapphire, which I owned and used before) does the same thing and you know why? Because Sota wants to solve the speed issue from previous models! As mentioned by Michael Fremer in Stereophile, on many suspended turntables the motors are "hard-mounted to their bases; when the subchassis was horizontally deflected, the platter-to-motor pulley distance would vary, causing speed irregularities."
I no longer own the old Sota Sapphire for a reason.
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