What turntables do you use? Pictures would be nice as well :-)

Ok, but I did the upgrade to a Transrotor turntable which has a Papst motor similar to the one in the picture you shared. Actually when I checked the picture you shared on above post I can clearly see that it is a 2 phase motor from the writings over it. It is manufactured in April 1977 and if you want to run it direct from the wall you need to add a 0,5uf capacitor to delay the second phase. I can clearly see a red 0.47uf wima capacitor added to the circuit for this purpose which becomes redundant when 90 degrees two phase AC supplied by external power supply

I asked why 3 phase because almost always 3 phase motors come with external power supplies and we know that is not the case with Thorens TD124. I still wonder how a 3 phase power supply can be used with a 2 phase motor.

You may ask why 2 phase motor is used widely on turntables because it is easy to delay the second phase with a capacitor and it doesn’t have to be precise to drive the 90 degree 2 phase motor but 3 phase motors require precisely set 120 degree 3 phases and only a power supply can provide it from standard 1 phase AC household electricity.
Most Papst motors are build as three-phase as can be seen in the technical data sheets, a Bodine NYC-12 is a two-phase motor with two coils , Papst have three coils.
 
Most Papst motors are build as three-phase as can be seen in the technical data sheets, a Bodine NYC-12 is a two-phase motor with two coils , Papst have three coils.
I explained why they’re not 3 phase motors -at least the ones inside old turntables- but anyway I’ll be happy to learn if you share an original Papst motor’s data sheet that is actually used in TD124 or other old turntable.
 
The Pabst motor i am using is a 3 phase capstan built for a special version of the Studer A80, not 100% synchronous but can be controlled by changing voltage and frequency , i have modified the bearing assembly to make i more synchronous. It sounds better than the other motors i have tried, very dynamic and punchy in the low frequencies.IMG_2738.png
 
  • Like
Reactions: shaizada and mtemur
Pabst external rotor motor, direct replacement for Berger E 50 motor. I didn't think it sounded any better. Better to take the Berger apart, put in new ball, bearing bushes and new felt and then oil it with good sinter oil. Then the thing will run smoothly for the next 30 years. Put an adjustable transformer in front of it, set it to 215 volts and be happy.
Shematics pabstimages (5).jpeg
 
  • Like
Reactions: mtemur
I explained why they’re not 3 phase motors -at least the ones inside old turntables- but anyway I’ll be happy to learn if you share an original Papst motor’s data sheet that is actually used in TD124 or other old turntable.
As you know to find out what kind of motor it is you can use the motor itself as generator this is what I have done with the Thorens 902 5014 07 motor in the picture , 120 degr between the coils .
Also a statement from Papst itself that the motors have standard a three phase coils that can be used with a phasecap at a single phase supply.
 

Attachments

  • thumbnail_20240408_085254.jpg
    thumbnail_20240408_085254.jpg
    562 KB · Views: 20
  • 20240408_084526.jpg
    20240408_084526.jpg
    668.8 KB · Views: 18
  • 20240408_084423 (1).jpg
    20240408_084423 (1).jpg
    513.7 KB · Views: 16
  • 20240408_084400.jpg
    20240408_084400.jpg
    546 KB · Views: 13
  • Like
Reactions: Lagonda
Pabst external rotor motor, direct replacement for Berger E 50 motor. I didn't think it sounded any better. Better to take the Berger apart, put in new ball, bearing bushes and new felt and then oil it with good sinter oil. Then the thing will run smoothly for the next 30 years. Put an adjustable transformer in front of it, set it to 215 volts and be happy.
Shematics pabstView attachment 128257
The Papst is a better motor then the E50 imho but you need to tune the phasecap with single phase drive for minimal vibration.
But as said earlier three-phase is the best solution , you never get a shaded pole motor quiet from itself , decoupling with springs gives is the best way to go.
 
The Pabst motor i am using is a 3 phase capstan built for a special version of the Studer A80, not 100% synchronous but can be controlled by changing voltage and frequency , i have modified the bearing assembly to make i more synchronous. It sounds better than the other motors i have tried, very dynamic and punchy in the low frequencies.View attachment 128254
 
The Papst is a better motor then the E50 imho but you need to tune the phasecap with single phase drive for minimal vibration.
But as said earlier three-phase is the best solution , you never get a shaded pole motor quiet from itself , decoupling with springs gives is the best way to go.
I believe you immediately that a three-phase drive produces excellent sound. I have other adjustment screws that are more effective for me. A good plinth that absorbs noise (mine weighs 65lbs), set up the tonearms separately from the frame, no mechanical connection to the Thorens. The whole turntable on slate with air suspension. Next step: battery operation with sine wave inverter (from ambulance), excellent, clean sine wave 220 volts.
 
Pabst external rotor motor, direct replacement for Berger E 50 motor. I didn't think it sounded any better. Better to take the Berger apart, put in new ball, bearing bushes and new felt and then oil it with good sinter oil. Then the thing will run smoothly for the next 30 years. Put an adjustable transformer in front of it, set it to 215 volts and be happy.
Shematics pabstView attachment 128257
It is a two phase motor. Maybe it is 3 phase or even 4 phase but according to schematics it is driven by two phase.
 
Last edited:
As you know to find out what kind of motor it is you can use the motor itself as generator this is what I have done with the Thorens 902 5014 07 motor in the picture , 120 degr between the coils .
Also a statement from Papst itself that the motors have standard a three phase coils that can be used with a phasecap at a single phase supply.
Thank you for sharing pictures.
 
Last edited:
I believe you immediately that a three-phase drive produces excellent sound. I have other adjustment screws that are more effective for me. A good plinth that absorbs noise (mine weighs 65lbs), set up the tonearms separately from the frame, no mechanical connection to the Thorens. The whole turntable on slate with air suspension. Next step: battery operation with sine wave inverter (from ambulance), excellent, clean sine wave 220 volts.
sounds like good recipi getting straight to emergency room...... :D
 
  • Haha
Reactions: bonzo75
I believe you immediately that a three-phase drive produces excellent sound. I have other adjustment screws that are more effective for me. A good plinth that absorbs noise (mine weighs 65lbs), set up the tonearms separately from the frame, no mechanical connection to the Thorens. The whole turntable on slate with air suspension. Next step: battery operation with sine wave inverter (from ambulance), excellent, clean sine wave 220 volts.
Yes good solution
It is a two phase motor. Maybe it is 3 phase or even 4 phase but according to schematics it is driven by two phase.
It is a two phase motor. Maybe it is 3 phase or even 4 phase but according to schematics it is driven by two phase.
No not a two phase

I understand that you cant read German language

Let me translate what Papst said about the motors in the documentation

,,, Papst aussenlaufer motors were mainly build with three phase coils ,,
 

Attachments

  • thumbnail_20240408_085254.jpg
    thumbnail_20240408_085254.jpg
    562 KB · Views: 3
  • Like
Reactions: DasguteOhr
I understand that you cant read German language
I can read German but I don’t understand cause I don’t speak German.

Thanks for translating it but Google has already helped me to translate it to English before you did. According to the document in German that you shared, the motor, even though it has 3 phase coils, it can be run on a single phase by adding a capacitor. Which means 2 phase. That’s why and by looking at schematics that @DasguteOhr shared I concluded that;

“Maybe it is 3 phase or even 4 phase but according to schematics it is driven by two phase.”

Ok, it is a 3 phase motor show me 3 AC lines feeding the motor in the picture (this is the picture you shared).

IMG_0040.jpegI can only see one phase AC line feeding the motor and second phase is generated by a capacitor. Exactly as explained by the German document you shared. As a result 2 phase driving the motor.
 
Last edited:
  • Like
Reactions: DasguteOhr

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu