Stay tuned on the weekend. Building the motor pod and will test the belt drive assembly is the goal.
Looks like a 2M Red. You'll eventually want something better. 🙂
Great project BTW.
jeff
Thanks for the feedback.
Yes. It's a 2M Red. If I get is spinning and tonearm working with the 2M, we'll see where we go! What do you suggest for bang for buck once i get things running with the 2M Red?
Yes. It's a 2M Red. If I get is spinning and tonearm working with the 2M, we'll see where we go! What do you suggest for bang for buck once i get things running with the 2M Red?
The online community seems to really love the Audio Technica VM540ML, so that might be a good place to start. I'll admit I've yet to hear one.
jeff
jeff
Super curious to see what you have for the motor and controller. I have been playing with various BLDC motors with Arduino shields, and having good results.
As an alternative I would recommend the SG4,
https://www.diyaudio.com/community/...e-generator-for-turntable-motor-drive.298018/
https://www.diyaudio.com/community/...e-generator-for-turntable-motor-drive.298018/
Last edited:
Hi, A few things you need to know & take into account
-What is the Eff Mass of the tonearm. You need to work out this figure to you can decide what cat best suits your arm. It is important that the cart & arm match so the resonant frequency of the pair falls between 7 to 12hz
- For driving the platter you will get far ore consistent results by making & using a Mylar tape belt, cost around 5cents.
- You also need so sort of mass loading for the plinth to stop unwanted vibrations getting through to the platter & hence cartridge (TNT audio mag a few years ago did an interesting group tests of a kit T/T from TemaadAudio)
https://www.google.com/url?sa=t&rct...usg=AOvVaw13Mi8nIeHQPY4QWoQMYfUR&opi=89978449
Cheers
-What is the Eff Mass of the tonearm. You need to work out this figure to you can decide what cat best suits your arm. It is important that the cart & arm match so the resonant frequency of the pair falls between 7 to 12hz
- For driving the platter you will get far ore consistent results by making & using a Mylar tape belt, cost around 5cents.
- You also need so sort of mass loading for the plinth to stop unwanted vibrations getting through to the platter & hence cartridge (TNT audio mag a few years ago did an interesting group tests of a kit T/T from TemaadAudio)
https://www.google.com/url?sa=t&rct...usg=AOvVaw13Mi8nIeHQPY4QWoQMYfUR&opi=89978449
Cheers
Thanks for the suggestions. I haven no idea how to measure resonant frequency. I will know the mass and effective mass and have a device to measure the weight of the cartridge on the record (a tiny scale) to be the appropriate grams for the cartridge I bought 2M Red. I am working on the appropriate counterbalance weight for the tonearm before I get them machined.
Plinth is solid maple with small wiring channels drilled in where required. All of the pods are isolated from the plinth by .09 inches of neoprene rubber around the circumference and underneath the pods so that any vibrations are dampened and don't reach the gear hopefully. I don't know how to measure this effect.
The belts I am using are the same type of belts some high end manufacturers have used from my research anyway. I guess we will see how well they work. I will check out the mylar too!
Plinth is solid maple with small wiring channels drilled in where required. All of the pods are isolated from the plinth by .09 inches of neoprene rubber around the circumference and underneath the pods so that any vibrations are dampened and don't reach the gear hopefully. I don't know how to measure this effect.
The belts I am using are the same type of belts some high end manufacturers have used from my research anyway. I guess we will see how well they work. I will check out the mylar too!
Effective mass is calculated from the Moment Of Inertia (I) I = md^2, where m is the mass of the part and d^2 is the Center of Mass distance from the pivot squared. So putting it simply weigh all of the parts then find their balance point, measure the balance point distance from the pivot and square it. Add up all of the Inertia's when you have the total inertia Effective mass = I/L^2 where L^2 is the stylus distance from the pivot.
I would place the counter weight as close to the pivot as possible, what this does is reduce its tendency to waggle. I would also have the CW stub rigidly mounted (ie NOT decoupled)
The neoprene under the pods is not a good idea. It could cause movement in the pods which will vary Pivot to Spindle distance. You want the tonearm mount to be rigidly coupled to the spindle. I would add NO damping to the plinth, use the volume of the plinth to attenuate the energy path between Pivot and Spindle. You have increased this energy path by mounting the tonearm on a pod, this is a good thing IMO the further the energy has to travel the more it will attenuate.