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
The bearings are now the same (i.e. ABEC7) on all the Series V-derived models (= Series IV, 309 etc)and have been for a couple of years now.
You can hear this direct 'from the horse' mouth' if you look at a series of videos about SME on Youtube.Here is the URL of the first of the four (all relatively short):
http://www.youtube.com/watch?v=T8tbyVRsrKM
Best regards,
Dear Syntax,
Thank you for your nice photos.
It is clear that for ALL of my records, (your first photo) the prefered TONEARM'S ALIGNMENT is the Loefgren B.
The problem that I'm still have, is that I can't indentify those particular points on the TONEARM'S GEOMETRY, that dictates to a specialised/individual/unique alignment !
Not to be confused with the alignments of the B,L,S, IEC or DIN, (that depended by the way the LPs were printed on vinyl).
I'm really sorry that I'm posting about this again, but I've just figured a possible misunderstanding might occur about my quest.
What I mean is : When you look a tonearm, how can you see those points that require a modification in it's geometry ?
Is that all about setting new null points ?
I don't expect an answer, I'm posting this just to clarify.
Thanks again.
Dear Geoch, I do not want to step on any toes here, but in general, a "cardanic" = gimbal bearing does in no way hinder a design approach to give a tonearm dynamic balanced mode.
It is VERY difficult however to apply dynamic balanced mode to a uni-pivot tonearm (it is possible however..).
It is just, that there are "camps" in audiophile analog community and at least a few of them do not really "favor" dynamic balanced mode.
Why this is so, is beyond my limited horizon.
Interesting to note however, that many of those great japanese tonearm designs which have stood the test of time - Micro Seiki MA-505 and MAX, Pioneer/Exclusive EA-10/Pa3, Fidelity Research FR-64s and 66s - do feature dynamically balanced mode.
From the point of view of mere physics and technical engineering, dynamic balanced mode has a few good advantages vs static balanced mode - at least regarding guiding a cartridge with compliance through the groove of a record which is by nature NOT flat in a technical sense.
Cheers,
D.
Dear all, the last post by Syntax with the two photos showing the different cutting area ( and those weren't yet the absolute extremes of either school - have a look at some of the DMM cuttings from the 1980ies !! ) shouldn't be overlooked, as these pictures nicely illustrate a core problem of tonearm alignment.
The reason behind many "sibilance" and "distortion" problems and one of the reasons why longer tonearms in general are superior over a wider band of records.
Cheers,
D.
" dynamic balanced mode has a few good advantages vs static balanced mode - regarding guiding a cartridge with compliance through the groove of a record which is by nature NOT flat."
Excellent!
But what if this feature is the most critical ?
And what if we accept that probably the bearing friction on tonearms with ball bearings is considerably more than knife-edges, cardanics & unipivots, and this advanced feature can not incorporated in them or in a air bearing tonearm...
Does this pointing us the way of designing better tonearms?
Can we include this feature in a more sophisticated bearing ?