turntable motors...

we're in the same predicament. check out the maxon motors that teres uses (special for them, they say)

i was actually searching for some answers yesterday and this is what i saved that came from vinyl asylum

"Depends what you need.Do you need a whole kit or can you build everything yourself if you purchase only the bare motor?On which type of turntable do you want to mount it?
The www.teresaudio.com site sell the whole complete set for $375 plus shipping but it is compatible only as a stand alone unit.Look them up.Their motor is sourced from Maxon of Switzerland and the catolog number appears in their website. Maxon DC motors are sold by the company or their distributors. The motors which are relevant for turntable use are #110189( the one sold on the teres site),the
2326-942-12-111-050 and the 2326-949-12-111-050.These last 2 models are a few years old(about 4-5 yrs).The 949 version is the best of the three.You will need a simple regulator like the LM338 to obtain perfect stability of the speed.You will also need a precision pulley.
There are two excellent articles on the subject in two old magazines of Sound Practices, #10 and #11. There is also lots of info on the teres site if you have the patience to go through all the relevant emails.
I purchased the 942 version as a bare motor from the agent in Israel(that is where I live), and a very sophisticated variable stabilized DC power supply from a junkyard for peanuts.The teres guys(Chris Brady)sold me one of their excellent pulleys which I fitted on my motor.
The price of these motors(the 942 which I purchased- and the type which teres use) in Israel is around $85.If you decide to build your own and have trouble sourcing a motor, email me and I will try to help you out.The price of shipping from Israel is relatively cheap.
Have fun."

nerd of nerds,

>>hello, i was wondering what kind of motor i should use in a turntable...i >>was wanting to build a cheap one to experiment with...

I ordered a OriginLive motor with the regulator Pcb and installed it on my Thorens TD 145 ; the only thing was to build a 8 Volts DC power Supply
The motor is fitted with a pulley, and the regulator has 2 pots to adjust the
speed in 33 and 45 tr/min ; easy to install. No humm, good stability results on 33 and 45 tr on a flip of a switch.

I don't remember the cost, but I can check if needed.

Regards.

Alain.

DC Motor

Whatever type you use, I would suggest a DC device, as your pitch will be slightly more constant.

If you can find one, an old reel-to-reel motor has lots of torque and many have a feedback winding for control.

nerd of nerds,

The motors used are DC cogless types in the range 8 to 24 volts
Speed about 150/300 tr/min depending of the pulley size

for the power needed about 10 to 20 watts for a light platter
to 20 to 30 watts for a heavy one.

I have been searching for about 1 year ; I am going to build a TT
with the arm a schroeder style ...

but first I have to finish my preamplifier and then my phono pre.

Regards.

Alain.

Dare I mention a digital PLL speed control?

Hey,

Could anyone please further elaborate on the regulators and speed control units?

Can these be purchased “of the shelf”? Cost? what are the different options?


Regards

Izhak

synchronous motor

and why not AC synchronous motor with electronic frequency changer as for example Pro-Ject Speed Box ? This must be cheap and good solution.

Whatever type you use, I would suggest a DC device, as your pitch will be slightly more constant.

Click to expand...

I am curious why you say that. DC motors probably have lower vibtrations but better pitch?! What's wrong with the good old synchronous motor as far as pitch is concerned?

Geek said:

If you can find one, an old reel-to-reel motor has lots of torque and many have a feedback winding for control.

Click to expand...

I'd be interested in exploring that idea, i have a number of these lying around...

dave

I have spent a few months building a t/t using the same type of motor as Rega/Notts Analogue i.e. 'premotec' a/c motor- and using the lowest power available. This seems to work very well on the NA turntables and my own (platter is 3.5 inches deep made of solid/dense wood with lead shot inserts) - the motor is incapable of starting the platter but after a little flick it will sustain the speed (confirmed by ear and using the strobe from John Daniel).

These motors do appear on ebay from time-to-time - but of course the pulley may not be correct for your needs. The pulley I made (out of wood) took some time to machine / sand to size - mainly because I got my calculations wrong!

Have fun!

an old reel-to-reel motor has lots of torque

Click to expand...

The PAPST outer rotor type is superb - almost vibration-free, little external e-m field, and a built-in flywheel.

I use one of those PAPST motors and it gets a little loud when under the latteral force of the belt, under no load it is almost inaudible.
It is really stable and has enough torque that stylus drag or wieght of my platter are not an issue.

Hi,

I'd be interested in exploring that idea, i have a number of these lying around...

Click to expand...

Allow me to doubt it would be worth the trouble.
Most R2R motors have way too much torque to be useful as a TT spinner really.
Maybe if you can tame one and keep it outboard, potted in a concrete block, it might work.

Cheers,

fdegrove said:

Maybe if you can tame one and keep it outboard, potted in a concrete block, it might work.

Click to expand...

LOL!!

Maybe end up with a "Tim Taylor" direct-drive turntable - can double as a centrifugal dryer for your rainsoaked convertible

Most R2R motors have way too much torque to be useful as a TT spinner really.

Click to expand...

Can you give a good explanation why this makes them unsuitable?

Can you give a good explanation why this makes them unsuitable?

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FWIW high torque usually means high vibration and most modern belt drives prefer relying on inertia rather than torque. Some are not even capable of starting the platter on their own or have to switch to higher current at strart-up. It seems that after reaching certain inertia of the platter the drive system becomes a lot less important as long as it stays quiet.

Whoever disigned my 301 was obviously not aware of this theory

The motor in the 301 isn't a synchronous motor, so it has smoother rotation. Its own flywheel effect at 1500rpm with a heavy core is significant and able to override/smooth the applied rotating magnetic field. Conversely, synchronous motors have a light rotor spinning at 250rpm that are locked (synchronous) to the rotating magnetic field. Reducing the voltage applied to a 301 motor reduces vibration, but I expect you knew that..