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This is not my first SS cartridge-I previously had a SS Zephyr mounted on my VPI Classic. This is the first time however that I have tried to mount this Zephyr MIMC onto my VPI Prime with 3D arm. I don't understand how or why I should need to shove my cartridge all the way back against the headshell, as far as it can possibly go, to get the right overhang. I thought VPI and Peter of SS even worked together a bit to optimize the Zephyr for VPI tables. I used not only the VPI supplied gauge but also my Mint Tractor to confirm the overhang point. Not only is it unsightly to my eye to have my cartridge shoved as far back as it can possibly go, but it makes viewing the cantilever for purposes of proper alignment next to impossible. Any tips, suggestions, observations?
Follow Ups:
For what it is worth, my Prime has a pivot to spindle distance of 261.5 mm rather than the specification 258 mm. The fix in my case was to use a protractor made to the actual 261.5 mm.
> The fix in my case was to use a protractor made to the actual 261.5 mm.
That's not a fix! The fix would be to install a longer tonearm or else correct the mounting distance. There are probably many cartridges that will be impossible to align based on your so-called fix.
Best regards,
John Elison
Well John we have argued about this before. The proof of the pudding is in the eating. My cartridges align just fine, all six of them including ones from Ortofon, Audio Technica, and Stanton. I have used a protractor that you made for me (thanks again for that) and an Accutrack. They all fall into the middle range of the slots too. I can't say that every cartridge would work, but consider that my actual measured distance is off by 3.5 mm and the length of the slots is ~13 mm, or plus or minus 6.5 mm from the center of the slots. Given those parameters and assuming the arm length is correct, there should be a reasonable chance for success using this method for most cartridges and if not, what is lost by trying? There is more than one way to solve any problem of course and I offered mine in good faith, not to get into an argument over it.
Bill
I find it very hard to believe your headshell slots allow total movement of 13-mm, but I'll take your word for it. The headshell slots on my Technics headshells allow total movement of only 8-mm or plus-and-minus 4-mm. I hope you realize you have to measure from the center of the screw at one end to the center of the screw at the other end and not the full length of the slots. Anyway, I'm glad you're happy!
Sorry,
John Elison
"I find it very hard to believe your headshell slots allow total movement of 13-mm..."
Language can be so imprecise. I said the length of the slots on my 3D arm is ~13 mm. Using the same methodology, I checked several of my Technics headshells and the length of the slots is ~10 mm, which equates pretty well with what you are measuring approximating center to center of the screwheads. So there is a bit more room for adjustment on the VPI arm, which is a good thing since there seems to be a bit less precision coming out of New Jersey than out of Japan. God what a couple of nerds we are. But all is well, yes I am happy. Take care.
What method did you use to arrive at such a precise S-P distance?
Because the 3D tonearm is a unipivot it is easier. Remove the tonearm and then use either a steel tape (Stanley makes a nice one) or even better, a high quality steel ruler and measure pivot point to center of spindle. This is not difficult to do at all.
You may find it easy to do and I don't doubt your measurements to half a millimeter of precision, but I don't find it easy nor do I share your confidence. I tried measuring with both my platter and tonearm removed. I am not about to lay a metal anything against the platter bearing or the tungsten tip. Even if I did, there is a height difference which will throw off the measurement. So I feel my best efforts only provide an estimation. In my case I got 257.2 mms but it all depended upon how I sighted down vertically from my rule to the bearing center and pivot point-not something that can be done with engineering precision IMHO. This is why Mr. Ellison posted about his method which calls for measuring the height difference and subtracting out the hypotenuse (IIRC).
There is no need to sight down vertically. Lay your ruler on the top of the spindle to the top of the unipivot and make a measurement. Next lay your ruler on top of the unipivot level with the platter and measure the height from the spindle to the ruler. You now have two sides of a right triangle, the hypotenuse, "c" and the short side, "a." Apply Pythagorean's theorem.
b 2 = c 2 - a 2
I believe you can make a very accurate measurement of spindle-to-pivot mounting distance in this manner.
Good luck,
John Elison
I think John is right, the arm is probably not mounted exactly. Check this post from Harry saying it can be adjusted.
I've mounted my Zephyr MIMC on both a Scout with JMW 9 and Super Scoutmaster Reference with JMW 10.5i. The cartridge was closer to the front of the head shell in both cases.
Is the arm properly positioned on the pivot point? Sometimes the VPI protractor can knock it off the point.
.
Here is another pic.
I'm not sure what the problem is. If the cartridge aligns correctly all the way back in the headshell what difference does it make?
The only thing that matters is whether it aligns correctly.
FWIW I have a couple of cartridges that, because of their body shapes, are all the way back in the headshell.
Thanks for not making fun of me-my fingerlift is facing in and not out. Got that corrected-Duh! I notice too that with my Benz Glider which is installed on a second Prime 3D arm, same exact thing-I had to shove the cartridge almost all the way back (as opposed to ALL the way back with the Zephyr). But with my Benz Glider, I was still easily able to view the cantiliver to align it. I got the Zephyr aligned with the help of my handy-dandy "Illuminated Dual Lens Flip-In Head Magnifier" but like I say, I just don't care for the aesthetics. To me, it looks kludge-y. I still have to ask-are these two cartridges outliers and do most cartridges have shorter screw mount to stylus tip distance? I tend to think not and that VPI could do a better job designing the slots.
Once you are satisfied with your cartridge setup and get used to the sound, you might try it without the fingerlift installed.
I have no doubt that there would be a subtle improvement in sound. But, my other 3D arm is the second generation and it came shipped with the fingerlift broken off. It took out a good chunk from the headshell proper as well. For almost two years I have been using it as-is and though in no way a detriment, I do like having a fingerlift. That said, I can say from experience that a fingerlift causes more fumbling, not less. Without a fingerlift, one becomes accustomed to gently grasping the arm with two fingers on either side of the top of the headshell. This is a far more secure way of holding onto the arm. I think the fingerlift gives a false sense of security and it's easy to fail to get the finger under the lift and knock the arm sideways. If you cueing lever is not up, much cursing follows.
> Thanks for not making fun of me-my fingerlift is facing in and not out.
You know, I didn't even notice that when I looked at the picture. I had to go back and take another look. ;-)
My opinion is that VPI might have mounted the tonearm incorrectly. They seem to have a history of doing that sort of thing. Can you measure the pivot-to-spindle mounting distance? It should be 258-mm. I've got a feeling that yours is a bit shorter than that.
Does your Mint protractor have the dimensions printed on it. What pivot-to-spindle mounting distance is it designed for?
As Louie3 mentioned, if your cartridge is in perfect alignment, it really doesn't matter whether it is all the way back in the headshell slots. On the other hand, since it is all the way back, it might not be back far enough to be in perfect alignment. See if you can measure the pivot-to-spindle mounting distance. It might be easier if you remove the tonearm so you can measure from the center of the spindle to the unipivot. Here is a post I wrote explaining how I make that measurement.
Best regards,
John Elison
Cartridge is still towards the back.
-Wendell
Yeah, towards the back! Not all the way back!
Steve is using an ART7, which has a stylus-to-mounting hole distance of 11-mm and I don't think his is all the way back. Maybe he will chime in.
Best regards,
John Elison
John and Rrob, I appreciate your thoughtful responses. I will try to measure spindle to pivot as accurately as I can, and will double check that my arm is correctly on the tungsten finger-stabber :-) but...with my Mint Protractor, once I got proper overhang with the stock VPI gauge, I then had perfect overhang with the Mint at both null points. As you likely know, the Mint is custom made on a made-to-order basis for one's particular table. IIRC, the man behind Mint is a guy by the name of Yip who knows his stuff. My point being that the fact that two "gauges" were in unison tells me that StP distance is likely not the problem. I think that when someone at VPI-or their third party vendor connected with 3D printing-drew up the design perameters for the 3D arm, the headshell became intentionally or unintentionally elongated. Correct me if I am mistaken, but the length of the so-called headshell has zero to do with effective length of the arm.
I noticed after the fact that the Zephyr and the Zephyr MIMC (I have one of each) do not have the same length cartridge body-the MIMC is a tad deeper/longer. If I am mistaken here, perhaps Peter of SS will see this and correct me. Another interesting tidbit; with the MIMC shoved as far back as it would go in both slots, my MIMC had perfect stylus alignment per the Mint Protractor with zero futher adjustment. I am used to spending an hour or more adjusting, sighting, re-adjusting, re-sighting and on and on with the Mint to achieve perfect cartridge twist so that the stylus is properly aligned. I certainly was not expecting this default occurrence. I don't know whether to chalk it up to serendipity or incredibly good precision/QC at SS.
If your stylus follows the arc on the Mint protractor and your cantilever aligns to both null-points, you are good to go. It might look a bit strange being all the way back in the headshell, but your alignment should be good.
I suspect the problem is as you say, the headshell is elongated or else the tonearm is slightly longer than intended. However, the effective length from pivot-to-stylus should be correct so long as the stylus follows the arc of the Mint protractor.
Good luck,
John Elison
Totally depends on the cartridge body. Soundsmith cartridges have longer bodies than some.
One of the many reasons I prefer SME-slot-style arm mounts is that the mounting holes for the cartridge is/are fixed, and the base moves back and forth to set up overhang.
But all that aside, as long as the stylus falls on the correct point, forget about it and play records.
I suggest Shostakovich Fifth...Bernstein.
It is well back but not quite all the way.
-Wendell
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