STP distance. Is it critical ?

Dear Tketcham, I quoted Carr in my post from memory but the
thread is:'Allignment tool for SME V + Shelter'. To prevent any suggestion of 'belittling' the SME V I need to
add that all the owners , Carr included, are very fond about their tonearm. However even Carr admited that because of those holes in the headshell one needs to adjust the geometry to accommodate 'some carts'.As he put
it:'Simply recalculate and readjust the overhang,likewise
for the offset angle (the ...difference between screwhole diameter and srew diameter should be enough to accomodate the majority of carts)'. Well simplicity as well as complexity are persons-relative so I bought Triplanar because of my math.
While this thread is already complex I don't believe that
adding 'the range of tracking errors that sound similar'
will help to simplifid the issues.

Regards,

Hi, Nandric, I wasn't addressing anyone in this thread specifically, but I do think that talking about a range of tracking errors will help to clarify (and subsequently simplify) the issue of cartridge alignment. The endless debate over the "best" alignment geometry just confuses and frustrates people trying to align to the "best" geometry and their particular tone arm and cartridge doesn't allow it.

The problem is that many (if not most) tone arm and turntable manufacturers aren't forthright about which alignment geometry they used in the design and the owner is left to find the information themselves or figure it out by trial and error. When the owner tries to learn what they need to know they run into a sea of possibilities with often conflicting recommendations. Manufacturers should be more forthright about the geometry of their products and even provide recommendations and alternatives for alignment.

Because there is no standard for cartridge mounting holes or tone arm geometry I think the audiophile community should stop debating on the best alignment and start helping to explain the range of alignment possibilities for each combination of tone arm and cartridge. Web sites like Vinyl Engine have some very useful pages of information and graphing capabilities but even then it can be intimidating to try and figure out what you need to know and how to use that information.

Lastly, I think alignment template designers and manufacturers could be more accomodating of variable alignment geometries and include the ability to align for a range of geometries. There are excellent printable arc templates (protractors) that accomodate variable tone arm and cartridge parameters and there are a few excellent alignment protractors that can be purchased retail that have variable effective length/offset angle capabilities. But most alignment protractors/templates are designed for a specific alignment, such as Lofgren's A (Baerwald), with specific null point radii that may not be easily attained because of cartridge mounting hole parameters or headshell design.

SME's sliding base and alignment template is one of the most simple and easy to use combinations around. Even then, audiophiles complicate things by insisting that specific null points be attained, e.g., 66.0mm and 120.9mm, when a particular cartridge design may not easily allow for that alignment. The resulting SME alignment may end up instead at null points of 63.9mm and 119.1mm and be a perfectly fine (if not superior) alignment. But because it isn't using the so-called "best" null points the owner believes the SME alignment is inferior and not acceptable.

Custom protractor templates are available but they can be limiting in which cartridge designs can used with the tone arm and are of no use if the tone arm/turntable is sold. By offering alignment protractors that provide for a range of alignment null points depending on the resulting effective length, pivot-to-spindle distance, and inherent offset angle of each tone arm and cartridge combination, the cartridge alignment process would be much easier and understandable for the owner.

Best regards, Tom

Dear Tom, For those that are not blessed with mathematical talents: order the Mint tractor. That is what I deed.
Regarding your 'similarity argument' I am sorry but I was not able to resist the 'çhalenge'. In Holland we have the
saying:'from the rain in the drip'. To put it paradoxicaly
the identity relation is 'similar' to the similarity ralation. But the subject of identity is so 'easy' that nobody wants the demn thing. It is not part of logic nor mathematics or physics. So the philosopher got this subject for free . Your lucent Quine was nearly drown trying to explain this 'bathing in the same water in the same river' puzzle from some old Greek.

Regards,

Hi, Nandric, your use of Quine's argument is appropriate. The process of cartridge alignment can be as complicated as we make it but what is needed is an elegant method that considers a wide range of tone arm and cartridge combinations.

From W.V. Quine's paper titled "Identity, Ostension, and Hypostasis": "Elegance can make the difference between a psychologically manageable conceptual theme and one that is too unwieldy for our poor minds to cope with effectively."

Elegance in the case of cartridge alignment would be variable geometry protractors. And: "Where this happens, elegance is simply a means to the end of a pragmatically acceptable conceptual scheme."

Best Regards and enjoy the day.

Tom

Dear Tom, I also admire Quine but your problem is,uh, similar to the war that was meant to end all wars. To my
mind this is the lanquage issue. The capability of speakers to generate from limited lanquage resources a unlimited amount of sentences and questions. And this process starts very early. Look at those 5-6 years old kids. They look like asking-machines. While we of course are crazy obout them it is a wonder that we don't get crazy from them. But they have also the capacity to remember our answers so no wonder that at certain age they
refuse to listen to us. If our analog hobby survives for,say, 20 years I am sure that even then there will be
questions about the right geometry and the best way to adjust cart/toneamrm combo.
Best regards,