Cogging!

bimasta, If you hear no issues with the turntables you own, then how do you know the motor is guilty of cogging? Is it merely because they are iron core motors?

@lewm I just noticed your intelligent question. Honestly I don’t know; I guess because they don’t mention cogging, and usually non-cogging is advertised as a feature. Maybe you, or others, know: my DDs are Denon DP-80, and Micro Seiki DQX-1000.

Thanks for prompting me to think deeper, and sorry for not answering sooner.

Oh, and you never answered my question about the FR MC-201. So I guess we’re even... if anyone’s keeping count....

I prefer kegling to cogging. 

bimasta, I've never owned or even heard a FR MC201 cartridge, or any other FR cartridge, for that matter.  Does that answer your question, which I have forgotten?  (Sorry for not having come forward sooner.)

The Denon DP80 does have a 3-phase AC synchronous motor, or so I was told when mine was in for restoration.  Probably its an iron core type but built and driven to minimize cogging. Bill Thalmann thought its motor and servo control mechanism were advanced over the contemporary Technics systems. Denon published graphs to document its smooth running in their advertising literature.  (Imagine a modern company doing the same; well I guess one or two have done.)  I don't know much about the M-S DQX-1000, except based on my reading at Vintage Knob, it is an updated version of the DDX-1000, distinguished from the latter by its use of quartz-referenced speed control.

Thanks for the info Lewm, and sorry about the FR question — I confused you with another Audiogon member whom I follow closely.

The DQX uses a different motor entirely than the DDX — it's made by Victor — I don't know if it's the same as used in Victor's TOTL DDs. And apart from the quartz-control (which can be defeated in favor manual control, so it offers both) it also provides 40% more torque... also according to Vintage Knob. Sorry for the 'ad-speak'; I like mine, though the DP80 is a rung above in performance.

None of this resolves the cogging question however.