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
We all, I think, recognaze the individual right of belief
in our own hearing. So anybody is entiteld to believe in
his own ears. But to ekspect that anybody else should believe in your hearing is something totaly different. So
no wonder that only some of us use the VPI tonearms.
Regards,
Dear Nandric,

"reducing the complexity means to me not being able to deal with it"

not necessarily. reduction of complexity was and is sometimes a way of gaining new insights - one will believe or not. And it is also a survival pattern in some difficult situations enabling the individual to cope with it.

Of course you are right the psychological implications are also evident when it comes to results being feeded by personality habits avoiding or defending actions. You may conclude from special communication styles and patterns if the individual is able to deal with complexity or not, mostly using only one or two special behavior patterns showing over time. In this way most of us are not very well trained or prepared dealing with complexity.

thanks for your compliments. You are right I am a very optimistic person but having gained experience about "the real world" I do think that we need controversial discussion to some extent. This is what makes it different to the glossy magazines.

Dear Geoch, my calculations for several tonearms are based on my point of view that the last 3rd of the grooved area is more sensible to distortions and tracking error because in the 3-dimensional stereo groove the difference in angle between the inner and outer groove increases with decreasing radius.
That is creating already a difficult situation for the stylus' contact area.
Stevenson tried to solved this "stereo"-problem by simply setting the 2nd zero error at the DIN and IEC inner limit of grooved area.
Usually I aim to find a 2nd zero point between Baerwald/Löfgren A and Stevenson. Resulting in about as low average distortion as Löfgren B AND only slightly more maximum distortion compared with Baerwald/Löfgren A.
Important point IMHO is, that "my" maximum distortion figures are at the very beginning of a record - i.e. in that area, where the difference between inner and out groove wall is lowest and therefor least sensible to tracking error.
"My" idea of tangential calculation tries to get the best of both worlds while taking into account the fact that we are dealing with a 3-dimensional stereo groove here AND that the most critical (read: loudest, most dynamic, highest amplitude) passages in many genres of music do occur towards the end of a piece/movement.
So "my" calculation usually sports VERY low distortions in the last 15% of the groove.
I know what I am doing and I do know exactly why.
There is no secret here, but just a comprehensive survey and a critical look at the tonearms geometry, the stereo groove and the requirements faced with the records cut the last 5 decades.
No one has to follow my ideas nor do I postulate they are the one and only ones. I know however that they do give excellent sonic results and do take into account issues others have missed.
On the other hand, Löfgren A/Baerwald, Löfgren B and Stevenson - DIN as well as IEC - are all readily available as UNI-templates.
And there are some 9" IEC-based tonearms and small collections of modern records only (with rather long lead-out groove), where Löfgren B is certainly best.
But then there are too tonearms like a FR-64s and records like old Mercury SR, DECCA SXL, Verve and Impulse (to name just a few) which do "fare" way better with "my" calculation.

The UNI-Protractor is an universal precision positioning and alignment instrument. Independent whether you use "my" calculation for a few specific tonearms or whether you go for any of the "standard" calculations. Those are all options one can choose or dismiss.
You may noted, that I have not postulated a "Dertonarm"-alignment curve.
I only did some individual calculations for some specific tonearm designs.
That's it. Because generalization isn't always preferable.
I for one are neither on a crusade nor do I preach to follow my point of view only.
I have designed an instrument the serious audiophile can use with as broad a choice of options as possible.
Nothing more - but nothing less.
Hope I could clarify the point.
Cheers,
D.
Dear Nandric, any VPI tonearm can be aligned to calculation curves different from the one Harry Weisfeld favors.
And there are far more VPI tonearms out "there" than many think.
Cheers,
D.
Dear Dertonarm, My argument was not against the arm but against the designer arguments (phenomenal hearing capabiltys) BTW I am not used to argue
against lifeless objects.If I understand you well you or
your tractor can fix the problem(s). But more interesting, I assume, is the article by Keith Howard in Stereophile (March,2010) about the 'arc angels'. From him I also borrowed 'my' point about the O points . According to him the 'accurate cart. alignment is very difficult to achive, not least beacause the overhang and offset have to be set within extremly tight tolerances...' He also mentioned the 'whole hystory' from Percy Wilson till Stevenson. I was suprised to learn about the diffrence between the tracking error and the tracing error but more in particular that what Dennes calls Lofgren B 'just doesent't make sence to me'. Alas the whole technical story is to complex for a lawyer.
Which brings me btw to Thuchan.
Dear Thuchan , the reduction of complexity in casu is for
me a two O points protractor with O points in the right place. No need for me to comprehend all the technicalitys.
Like a average car driver who knows that there is something
called 'motor' in his car. So 'die praktische Vernunft'(the practical reason) is something differnt from
'die reinen Vernunft' ( Kant's 'pure reason'). Anyway the fact that you are still optimistic person despite your extended experiance deserves admiration.

Regards,

Regards,