Uni-Protractor Set tonearm alignment


Looks like Dertonarm has put his money where his mouth is and designed the ultimate universal alignment tractor.

Early days, It would be great to hear from someone who has used it and compared to Mint, Feikert etc.

Given its high price, it will need to justify its superiority against all others. It does look in another league compared to those other alignemt devices

http://www.audiogon.com/cgi-bin/cls.pl?anlgtnrm&1303145487&/Uni-Protractor-Set-tonearm-ali
downunder
Dear Pryso: +++++ " I do continue now to wonder if Dennesen considered other alignment calculations and rejected them, or if he simple accepted Baerwald because it was the most well known? " +++++

IMHO the precise and true answer only Dennesen could have it but I think that this could been take it in count for that Dennesen designer:

Löfgren A/Baerwald is the solution that gives you the lowest possible amount of tracking error at the inner, centre and outer grooves while keeping this error equal at all 3 points. This seems to me a good overall compromise.

Regards and enjoy the music,
Raul.
Dear all, "that Dennesen designer" was Francis G. Dennesen himself, together with Richard Wilson, Roy D. Toulan Jr. and Peter Madnick.
Cheers,
D.
Raul,

After this explanation, I am going to have to give up on this. I will stipulate that all the numbers you have provided above are correct. No dispute there.

I tested the original claim from many months ago (with an estimate I have labelled Dert63 above) against the original reference (245mm EL Baerwald or Lofgren). One does not, in fact, have to compare everything on a common P2S or common EL because in fact, the original claim did not.

In this thread, he made certain VERY specific and precisely qualified claims. Those claims were VERY clearly made on the basis of a certain opinion about record size (hence my use of DIN standard) and his own listening priorities (reduce distortion in the latter half of the record at the expense higher max distortion at the beginning), i.e. use a weighted distortion curve rather than an un-weighted distortion curve. Again you ask for proof. He wouldn't provide it, for what I now clearly see were good reasons not to, but I was curious, so I derived what I could based on these claims. As I have shown, each one of the claims seems to hold up when one does the math.

To my knowledge, NOBODY (not myself, Dertonarm, or anyone else) has EVER disputed the 'fact' that over a whole record, Lofgren B and Baerwald/LofA have lower average and lower equal-peak un-weighted tracking distortions than any other solutions for a given effective length. It is just math. Everyone stipulated this point long ago. Just to be safe, I repeated it.

His opinion about the qualitative aspect of tracking distortion across the record is clear. His listening priorities are clear. Based on his 'weighting', he has recommended and used something else than standard. That is his choice. As 'proven', his priorities would absolutely support use of Dert63 vs either of the Lofgrens. As you said, there are no 'absolutes' other than the math. It is some people's opinion that 'math' can be absolutely perfect in theory, and still applied wrongly sometimes.

The math stands up to support his priorities. The math stands up to support your priorities too. Everyone needs to make their own choices about priorities. I leave it there.

Kudos to Dertonarm for staying out of this. I should have as well.
Dear Pryso, no problem. My "question" was rather ironic and could easily lead to a misunderstanding. Mea culpa.
Cheers,
D.
Dear Nandric, dear T_bone, I discussed the FR-64s alignment parameters briefly with Klaus Renner (founder and editor of DAS OHR who sadly passed away while still in his thirties in 1991/2) in the mid-1980ies.
Based on initial proposals of A. Wagner/Munich.
In the early 1990ies - long before there was a VE-calculator on the web (heck - the web weren't really there back then (at least not in the sense we see it today)!!) - I calculated it a more in-deep and extensive.
On white sheets of paper with a pen, ruler and a pair of compasses ...... archaic today.
Anyway - I do not want to lecture anyone nor do I say that everyone has to follow my proposal or idea regarding the FR-64s tonearm.
It is a proposal, it suits my needs, allows the FR-64s to show it's virtues and to my knowledge has never failed to sonically impress a FR-64s-owner once he tried it.
When I give a proposal in audio is is based on my experience, proofed it's merit, is most likely at least worth a try and generally not a balloon.
That I like to go different ways should not disqualify me from the start.
So far and where I live this is a free world (so far and in some parts ...) and everyone can choose what he/she/it likes best.
Former Prussian king Friedrich "the great" put it very nicely more than 220 years ago: "Ein jeder werde selig nach seiner Facon!".
Cheers,
D.