High quality AC turntable motor

Lohanimal, a mains sign wave regenerator is what you need in the context of a controller for an AC synchronous motor. "Angling the power.." Sounds to me like another way of saying the same thing, hopefully. Perhaps the K K will be cheaper, but it ought to be much like the Merlin.

Hi Lewm - sorry for my lousy phrasse 'angling the power' I understand that with a 24 pole synchronous motor they can be made with 4 coils. If 2 opposing coils are driven, and then the other ones which sit at 90degrees to the driven ones are also driven then this ought to significantly reduce the ripple. PErhaps a fair analogy would be a two stroke to a four stroke engine. If it is the case that we have a higher torque motor, it's the magnets that help increase the torque, along with the commutator windings and thickness. As this increases, so does the clunking/cogging. That is why I want something that helps reduce this. A pure sine wave regenerator simply re-creates the 50 hz - it does not provide me with those 90 degree opposed waves to drive the other 2 coils. I hope that I make sense andd am barking up the right tree.

It seems to me that some of the posters here have forgotten some of their Trig. A complete sine wave cycle is 360 degrees. As the previous poster stated one set of field coils is driven by the primary AC current and the other with a AC current 90 degrees out of phase. This phase shift is usually accomplished with a capacitor (the current though a capacitor is 90 degrees out of phase with the voltage across it). Now, a sine wave generator with TWO amplifiers (thus two outputs), one 90 degrees out of phase, with the ability to "trim" the phase angle between the two has the ability to null out almost all motor vibrations. This is a distinct advantage over those sine wave generators with just one output. I own a Nottingham Wave Mechanic. I recently had it open to replace an output transistor that failed (it doesn't do too well with a single ended output stage). There is NOTHING special here. If the parts cost more than $125 I'd be surprised. Yet it retails for something north of $1200. They don't call us Audiofools for nothing. That's one reason I'm committed to DIY. Kevin's kit should provide a lot more "bang for the buck". The OEM power supplies are usually nothing more than an oscillator, a cheap amplifier and a transformer to boost the voltage output of the amp to 120V.

It would also seem that the manufacturer has taken phase into consideration in the manufacturer of the motor. If it runs from a wall socket, then it should be a matter of adjusting the voltage and alternating speed.

Hi all,

I am reading this thread with interest. The technical knowledge of some here, amazes me.

Having upgraded my turntable system to a three motor controller:
http://www.axissaudio.com/turntables/KM3.htm

In this German webpage, they discuss another turntable controller with amazing results. Seems like a real bargain compared to other controllers. http://www.frank-landmesser.de/hoer_analog_netzteil.html

I am very happy with the speed accuracy of this type of motor controller.

Still settling into our new house after our move back to the US from a lengthy tour of Europe.

Ciao,
Audioquest4life