AR XA upgrade path from basic rebuild onward

S

streetwise

Active Member
Hello I have recently acquired an AR XA turntable with a Shure V15 Mark II improved. I am currently building a new plinth out of solid walnut with dovetailed corners as mitered corners aren't very strong. I also cleaned up the base and repainted it with Primer and black paint. Cleaned the platter and oil wells pretty thoroughly. oiled the motor with sewing machine oil. cleaned and oiled the tonearm parts. The tonearm already had the damping system removed. I also cleaned the spring system and have it balanced reasonably. My question is what are the next step real upgrades for this turntable and what are the benefits of each upgrade. Im looking for real upgrades I don't believe everything I hear about upgrades so I would like a solid discussion here from Marc Morin and some of the other AR XA greats out there. Thanks any questions
 
One upgrade I will be moving forward with is replacing the two capacitors because the motor seems to hum when turned on... sometimes that is.
 
Do a search specific to Marc Morin. He's the AR guru on this forum. Lots of threads on this very subject with a ton of info.
 
I realize that and have looked unfortunately none of the threads ask the questions I want to ask and seem to be "definitive" they mention little bits of what marc has done on there turntable but don't describe what benefits or why they were performed
 
I think the best bang for the buck is sapphire cup bearings to replace the delrin bearings in the tonearm. Rewiring the arm is also a good upgrade. The motor has a normal vibration when not on but if you have a hum a motor brace may reduce or remove any extra noise.
 
The tracking ability of the arm becomes unbelievable better due to much less friction in the bearings. Since the wiring is 30-40 years old you may be able to get a better signal with new wire and isolate any ground problems also.
 
streetwise said:
One upgrade I will be moving forward with is replacing the two capacitors because the motor seems to hum when turned on... sometimes that is.
Click to expand...
The run cap can cause motor noise. Usually it will also cause the motor to run hot as well. Usually the noise from a bad cap isn't a hum. Check up/down play in the motor shaft. add oil to the motor where the shaft exits and let it run. dab it off every so often and add more oil. Sometimes the motor needs gone through. You should also check the coils with an ohm meter as follows. the top white wire and green wire are summed. check continuity to the other white wire and then red wire. You should have 6.3K or abouts in each. if one side is much higher, you may be looking for another motor.

regarding the things I have done to other's tables, is generally due. As Steve mentioned, arm bearings and rewire of the arm is a vast improvement.
 
I can say that the arm upgrade that Marc provides will make a significant sonic improvement and would be a good next step for the OP.
 
I will do the motor recap and possibly reoil after the recap. the bearings sound like a good idea along with a possible rewire. what other options would follow those for upgrades?
 
I just received new caps and will be installing this weekend. Where would I find sapphire cup bearings for this ar xa? Marc I also might do the rca's when I rewire can the ground just go through the left rca shielding like the original or will the new wires have to have a seperate ground wire? i would prefer it through the rca because the fisher 400 I use doesn't really have a grounding spot other than the speaker terminals that are super tight? any ideas
 
Also planning on using cardas wire for the arm, do I order shielded or unshielded? and I would like to use BJC LC-1 for the RCAs any recommendations on capacitance in cable I will be using my Shure V15 II possibly with a new JICO SAS stylus.
 
streetwise said:
I just received new caps and will be installing this weekend. Where would I find sapphire cup bearings for this ar xa? Marc I also might do the rca's when I rewire can the ground just go through the left rca shielding like the original or will the new wires have to have a seperate ground wire? i would prefer it through the rca because the fisher 400 I use doesn't really have a grounding spot other than the speaker terminals that are super tight? any ideas
Click to expand...

You don't need, want shielded arm wires. where they exit the arm pivot block twist one pair right, twist the other pair left, and then braid the ground wire with those two twisted pairs. They will be shielded that way. once they pass rough the top plate, unless you have a radio station in your basement, the plate will provide the shielding. At the back of your RCAs, sum the ground sides of them along with the arm ground and table ground. Makes for a quieter table.
 
In addition to the other mods being discussed, mass-loading the pulley and T-bar will significantly improve bass weight and PRaT. Marc did the work on my table, so he is better qualified than I to discuss the specifics.
 
marcmorin said:
You don't need, want shielded arm wires. where they exit the arm pivot block twist one pair right, twist the other pair left, and then braid the ground wire with those two twisted pairs. They will be shielded that way. once they pass rough the top plate, unless you have a radio station in your basement, the plate will provide the shielding. At the back of your RCAs, sum the ground sides of them along with the arm ground and table ground. Makes for a quieter table.
Click to expand...
I want to do as much as I can possibly do and then bring this turntable over to marc to do what i don't have the skills or equipment for. So the grounds will travel the ground of the left rca or both when they are all tied together?
 
streetwise said:
I want to do as much as I can possibly do and then bring this turntable over to marc to do what i don't have the skills or equipment for. So the grounds will travel the ground of the left rca or both when they are all tied together?
Click to expand...
the grounds will travel to both left and right cable shields..........it's where they end up at the preamp too. They are both summed there. Sum them ahead of time.
 
streetwise said:
I want to do as much as I can possibly do and then bring this turntable over to marc to do what i don't have the skills or equipment for. So the grounds will travel the ground of the left rca or both when they are all tied together?
Click to expand...

This is just m opinion, so take it for what it is worth. I would do the full package of upgrades in one shot. Pull the arm and send it to Marc for his complete refurbishment, and at least consider the arm tube swap. When you get the arm back, you know its done right and Marc has all the bits and pieces to properly do the vertical bearing upgrade. Have him do the downrigger upgrade to the subchassis, and the spring upgrade. The mass loading of the motor pulley, and even the spindle bearing polish. Whatever you invest in the AR upgrades and refurbishment you are going to be returned in sound quality. What Marc charges for his work is incredibly reasonable, and he knows how to squeeze the final bits of performance out of the AR table. If you were to have a boutique restoration shop do this work to a Lenco or Thorens TD 124, I would shudder to think what the bill would be. You are going to get a very high return for the money you spend on the AR. And you still are frugal by doing the tear down, refinish, and assembly of the table.

Regards
Mister Pig
 
Agree with everything above about Marc's work. And a note on the rewire of the arm. It's a beeeatch. Great that you're doing it because those original leads are in dire need of it(I learned the hard way and didn't have Marc do it when he was working on my XA) but yes, if Marc is going to be doing other things for you, I'd just have him do this as well. In the end, you'll at least saved yourself the aggravation(and there's quite a bit of that when rewiring one of these). And boy, those new wires really make a serious difference, and I'm the least picky about things like speaker wire, IC's, etc.
 
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