Turntable speed accuracy

Davide256: "What makes the finest turn tables is damping/filtering vibration at the micro level to prevent vibration reaching the arm and platter..."

Isn't this "vibration at the micro level" a form of movement and doesn't movement consist of timing? So a turntable that takes care of damping/filtering vibration automatically make it the finest disregarding strict attention to speed issues? Now I know where those toy motors are coming from...

Davide256: "You can consider direct drive the equivalent of attaching a vibrator directly to the platter... Next best is belt drive... the motor still vibrates but the belt provides isolation in power transfer."

You're repeating the flawed notion that Lewm already objected to in one of the above posts. I just cannot fathom someone discussing about "the finest turntables" without thinking about speed accuracy or the importance of speed accuracy as if that's a dated issue. I don't know what else to say. It reminds me of a Chinese saying about a cowhide lantern......

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Davide256, With all due respect, you are wrong. Linn is OK right after the suspension is tuned and for the next week thereafter. AR and SOTA, up to and perhaps not including their very latest TOTL models, are seriously flawed as regards speed stability. My SOTA Star Sapphire III was a distortion generator on piano music. Have you ever heard a real piano? Do you really like stretch-y belts and belt creep that much? And AR? A classic, yes. A bargain in its day, yes. But an example of how to build a speed-stable tt? Puh-leeeeeze.

Also and parenthetically, you don't understand the mechanism of a direct-drive turntable. I think I mentioned this to you somewhere above this last post. Do some reading on this subject. The issue in direct-drive is not noise but designing a motor that is free of cogging at slow speed. (The DD motor has to turn at 33 rpm, whereas belt drive and idler drive motors turn much faster. This tends to make them noisier than DD, not quieter, but a little easier to mask the cogging effect.}

But the syntax of your post actually suggests you like direct-drive better than belt drive. (You start with your criticism of direct drive and then begin your discussion of belt drive with the phrase "next best", implying dd is better, which it actually is when done right, IMO.)

Hi Thuchan,

I do understand that your system stands in Bavaria and it is located on-speed outside of Munich :-)

Also, I like following this attitude of "but sometimes fast driving"...out on the road! :-)

Always happy listening!

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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Dear Unoear,

(why not Duoear ?) you are fully correct. It is not a big problem finding me if you are not restricted to the US as some people seem to be, like Audiofeil for instance. Nevertheless this guy knows all kind of ice cream tastes and National League players (of the US of course) - hmmm maybe interesting.

But back to the topic. Has anyone really opened the Timeline and do you know what this means? Did you count the screws Halcro?

Unoear is a nice acronym. Is Duoear still available :-)

best @ fun only