Lewm, I was hoping you would click on the "Kenwood repairs (including three L-07D !!) prompt and click on any one of the L-07D buttons. (Obviously I am a finger clicking happy internet search fiend!) Check out all those dozens of hi-rez images of repair parts. Amazing clarity.
Lewm: "I think the field created by the coils would average itself out. (I also think there would be a limit to the odd spacing where once reached the field would no longer be able to average itself out and would result in a dead spot on each rotation.)"
He did mention that the Bardo works in a "soft drive" approach and, perhaps the L-07D might also work in similar way:
Wjsamx: "In regards to the Brinkmann motor, I can't understand the reason for the odd placement of the coils. One would think there is a dead spot of power in its rotation which is why I believe its concept is to push and brake. The motor seems by design to only pulse power to the rotation as needed. Once the heavy platter is at speed, the energy within its mass is creating the needed centrifugal force for rotation. The tach feedback will sense speed deviation and only micro-pulse the "motor" as necessary to keep the platter steady at speed, like cruise control. Judging by the size of the motor, it's not meant to "direct drive", it is just too small and weak. It's really a "soft drive" system. Weak micro-pulses of "magnetic" power to the platter would certainly not create a large impact on such a heavy platter, thus eliminating any cogging effect."
It reminds me of the belt-drive school of using weak motor to nudge the heavy platter to keep it up to speed and let inertia and flywheel effect take over. After all, Brinkmann is a mostly famous for the belt-drive turntables so they might be approaching DD with a BD mentality. Hey, if it gets the job done, I have no problem with that.
If it sounds good to you then that's what matters. I have some JVC motor with asymmetrical coil layout and they sounds very smooth to me. But I have to say the Dual 701 motor has a harmonic richness I don't hear from most DD tables and whether that has to do with its symmetrical coil arrangement or not, I have no idea.
Lewm: "He said or inferred that the Dual CS5000 would have an EDS coreless motor. But based on what I read at the Dual history website, that may not be the case. Just what models of Dual DO in fact have the EDS motor."
On the Dual Reference site, it does say the motor is "EDS 5000 System." It's a belt drive turntable so I don't know if the motor is usable for idler drive purpose or not. The most famous EDS motors are obviously in their two DD tables, 701 and 721.
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