Can I control the turntable motor speed of my Empire 598 electronically?

[Old Driver]

Help!!!!! I’m working on a new to me Empire 598.
It has a speed adjustment issue that’s driving me crazy.
I have the correct belt replacement from Esoteric Sound and have cleaned and lubed the bearing with fresh light machine oil and spent hours on trial and error mechanical adjustments. I get close to the correct speed and when I power it on the belt
flips from the 33.33 RPM spindle to either the 45 RPM spindle or the protruding knob above the 33.33 spindle.
Without the belt the platter spins effortlessly.
The best speed I have been able to achieve is + .70.
Is there an electronic solution to my speed issue? Would something like this from Amazon work?

AC Motor Speed Controller, Variable Speed Regulator for Fan & Power Tools | 120V 15A 4000W, overload protection & LED display, precise control, fits fans, drills, polishers, woodworking: Amazon.com: Industrial & Scientific

AC Motor Speed Controller, Variable Speed Regulator for Fan & Power Tools | 120V 15A 4000W, overload protection & LED display, precise control, fits fans, drills, polishers, woodworking: Amazon.com: Industrial & Scientific

www.amazon.com

 

[malden]

do you have the original belt?

can you post photos of the spindle?

 

[madwing]

have you replaced the original motor grommets?

 

[Old Driver]

have you replaced the original motor grommets?

Yes new grommets.

 

[madwing]

have you cleaned the capstan?

 

[loudnoises]

How's it jumping? Is it catching on the spindle or the platter?

Talc?

 

[Rickey_H]

My next turntable will be an empire. From what I understand, these AC motor are synchronous to the line frequency not the line voltage. As such, you will need a VFD (variable frequency drive) controller. However, your platter is turning slower than needed, there must be a mechanical issue that needs to be sorted.

 

[borchee]

I get close to the correct speed and when I power it on the belt
flips from the 33.33 RPM spindle to either the 45 RPM spindle or the protruding knob above the 33.33 spindle.

How can you get close to the correct speed with the TT powered off?

What do you use to measure the speed? You shouldn't worry about it at the moment, but about the belt behave the way it should.
Anyway, you should check the speed under load/playing a record, when the belt issue is sorted.

 

[OBMG74]

Can you post a video of the belt jumping?

Anyway, you should check the speed under load/playing a record, when the belt issue is sorted.

^^^ And this.
I like using a strobe disc and fluorescent light. Close enough for me...
My 598's speed is fine with a FM 31.5 belt from turntablebasics.com but it was purchased 10 years ago...

 

[gadget73]

You can use a speed controller to change speed, but it won't correct for wow or flutter caused by mechanical issues. All they do for synchro motors is control the frequency they are provided with which changes the speed of the motor itself.

No clue about the one linked, but they do make such devices specifically for turntables with highly accurate frequency generators in them to maintain very stable output frequency. Most of them also have multiple speed options so you don't have to shift the belt in order to go from 33 to 45.

 

[malden]

Help!!!!!

if you would provide some useful information, we may be able to help

 

[OBMG74]

Another question:

Is the platter setting to high because of too much oil in the well, causing the belt to move up or down?

 

[Old Driver]

do you have the original belt?

can you post photos of the spindle?

do you have the original belt?

can you post photos of the spindle?

No the turntable came without a belt in finder’s condition. Here are pictures of the spindle. Also, when cleaning out the plinth I discovered this aluminum threaded spacer that I can’t figure out its purpose. It fits the diameter of 5m screws holding up the motor assembly and its threaded but long since stripped. Any thoughts on this?

 

[Old Driver]

have you cleaned the capstan?

Yes, I cleaned capstan with rubbing alcohol on a Qtip. I cleaned the belt in water and a few drops of dish soap, throughly rinsed and air dried over night also.

 

[YY1]

Sure looks to me like the belt is not riding in the correct spot on the capstan- like it should be in the "spool" shape.

 

[Old Driver]

How's it jumping? Is it catching on the spindle or the platter?

Talc?

It’s catching on the spindle.

 

[Old Driver]

My next turntable will be an empire. From what I understand, these AC motor are synchronous to the line frequency not the line voltage. As such, you will need a VFD (variable frequency drive) controller. However, your platter is turning slower than needed, there must be a mechanical issue that needs to be sorted.

How's it jumping? Is it catching on the spindle or the platter?

Talc?

It’s catching on the spindle

 

[Old Driver]

Another question:

Is the platter setting to high because of too much oil in the well, causing the belt to move up or down?

Another question:

Is the platter setting to high because of too much oil in the well, causing the belt to move up or down?

Attached is a pic of the height. I put the Qtip in there for scale. If I go lower, the belt rubs against the bottom of the platter. The belt doesn’t ride in any grove on the platter. It’s smooth. Might the belt be riding too high on the platter? If so, how do I get it to ride lower?
I cleaned out the platter well before re-lubricating. I didn’t fill the well with oil. I just liberally coated the platter spindle before lowering it back onto the cleaned well.

 

[Old Driver]

How can you get close to the correct speed with the TT powered off?

What do you use to measure the speed? You shouldn't worry about it at the moment, but about the belt behave the way it should.
Anyway, you should check the speed under load/playing a record, when the belt issue is sorted.

I’m using an app on my phone. I set the speed as close to 33.33 RPM while the turntable is running. After getting it as close as possible to correct, I turn off the turntable, remove the phone and power it back on to use it.
It on this repower that the motor torque pushes the belt on to either the lower 45 rpm or the knob tip of the spindle above the 33.33 rpm spot

 

[Old Driver]

Can you post a video of the belt jumping?


^^^ And this.
I like using a strobe disc and fluorescent light. Close enough for me...
My 598's speed is fine with a FM 31.5 belt from turntablebasics.com but it was purchased 10 years ago...

I’ll try to take a video when I return home later this afternoon.