MintLP Protractor for the JMW-9T tonearm


I was just about finished with my order of a MintLP protractor for my Scout's JMW-9T tonearm when an issue with the geometry of this particular tonearm arose. Yip from MintLP at first assumed the tonearm was the regular JMW-9, which has the same effective length as the Signature version. When I sent him a link to the description of the 9T from the VPI website to make sure he knew it was the upgraded version, he said he had made a mistake as the description stated that the 9T had the same geometry as the Rega RB-300 and could be dropped onto any Rega armboard. He suggested I contact VPI to get a definitive answer about the 9T.

So I did contact VPI and they responded that the 9T indeed has the same geometry as the Signature and the same as the Rega. So I'm now a little confused why Yip seemed to think the Rega RB-300 and the JMW-9 have different effective lengths? Is anybody familiar with the above mentioned tonearms and can confirm either way to settle this? I'd hate to waste over $100 on a custom made protractor if it's made on a wrong assumption.

Thank you.
actusreus
Actusreus... I'm not sure of or completely clear on the implications your posting on 04-02 might have for someone like me who has a ScoutMaster with the stock JMW9 tonearm and uses/has used the appropriate "9" Mint LP Tractor to set that up. Can anyone clarify as best they know/understand Actusreus' post?

:) listening,

Ed
Istanbulu,

The Mint protractor for the JMW-9 tonearms is made based on the mounting distance of 223mm and effective length of 240mm based on the Baerwald algorithm, which Yip uses for his protractors. The mounting distance of 223mm is what VPI used to officially state on their website before removing it. That's why Mint has been making their protractors based on these numbers. However, the vinyl engine article linked in the first response reports that the actual mounting distance on the JMW-9 is 222mm, not 223. I measured mine and it indeed appears that it is 222mm. This would also comport with what VPI told me in response to my email, i.e., that the JMW-9 has the same geometry as the Rega RB-300, which has the mounting distance of 222mm. If so, the protractor for the JMW-9 tonearm should be made based on the mounting distance of 222mm and the effective length of 239.5mm under the Baerwald algorithm, and NOT 223mm and 240mm, respectively.

That is why I wonder if the JMW-9 protractors are actually correct. Because VPI refuses to reveal the actual measurements, it is difficult to determine exactly what numbers the protractors for VPI tonearms should be made based on. That's why I wanted to try a set-up with both to compare.

Hope this clarifies my previous post.
Actusreus... thank you, and I was afraid you might actually be saying what you said (if that makes any sense!).

So at this point I wonder what to do. I wonder what the net musical effect of this might be.

Earlier today, I sent an email to Yip alerting him to this thread, and I hope we all hear from him. He strikes me as a straight-up guy who wants to get it right and do the right thing.

Now as it relates to VPI, it sure would be helpful if they joined the discussion in a transparent and informative manner as well... jmo and hope.

:) listening,

Ed
First off, Yip has been extremely professional and helpful. I have no doubt his product is the best of its kind out there. I would hate to give even a hint of impression that he has done something inaccurate or incorrect, when quite the opposite is true. The blame for anything rest with VPI that has been rather unhelpful by not providing accurate data for their product, which is necessary to get the best out of any analog system.

I now almost regret I started this thread as I fear it might be causing more harm than good. I wanted to get an advice but it appears it has opened the proverbial can of worms and for this I blame myself as well and I apologize.

As for your question, Istanbulu, if you have been happy with your system, continue enjoying your system! My Scout was set up with the VPI jig that is inferior to Mint protractor and without a magnifying glass. And guess what? I love it! I wanted to use Mint to make sure I'm getting the best out of my cartridge, but that doesn't mean I can't be enjoying my music without it. If it sounds good to you, it's all that matters.
Hi Actursreus... I agree about Yip and his professionalism and especially his protractor... it improved the enjoyment of my TT immensely, and in fact returned my interest in vinyl recordings. Buying his Mint Tractor was my last effort at asking myself if the expense and general labor of vinyl was worth it. When I used his Tractor to adjust my Scout and now because of the remarkable results of his Tractor, I upgraded to a Scout Master, and I was and am astonished at the musicality, etc. of what I was/am hearing. A tremendous improvement in many respects.

When/if you find out more about the issues that have emerged in the progress of this discussion, I would be very interested in how they affect the listening experience.

:) listening,

Ed