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 Geoch, I have good news and bad news reg.SAEC.
The good news is that you can download the user manual for
the WE-308 NEW from Vinyl engine. The bad news is that there is no mention of the zero points by the specifications. I wrote there 61/89 but have no idea where I got this info from.
Your quote from the VA is probable from Kessler& Pisha;
Tonearm Geometry and Setup (Audio, January 1980). They
suggest to use SAEC geometry and setup. If I am well informed ony the WE-407/23 allows 'the usual' geometry (aka
Baerwald).

Regards,
Thank you all for your kind responses.
Unfortunatelly the users manual can not help but rather making the situation much worst & perplex.

If I get it right ...
Dertonarm is the only one who suggest a different alignment than the Baerwald IEC. It seems to me that he explores some new or underestimated parameters in tonearm geometry and obviously he discovers a relationship between the alignment for the least tracking error & the alignment for better control of resonance for any given tonearm !
Every other guy in my search, -all of them- are following the usual Baerwald IEC :

John Elison about SAEC WE-308 :
http://www.audioasylum.com/audio/vinyl/messages/78/788115.html

Wally Malewicz suggesting : "to use dedicated W-tractor for Rega Arms , but be prepared to twist Cartridge in the Headshell"

Allen Wright that from 1982 becomes the Australian importer claims about the WE-407/23 :
"...and am actually responsible for the /23 part of the model number. It stands for the 23 degree offset (bend) angle of the headsheel that is correct for the two point "western" arm/cartridge aligment as used today.
The original 407 used the non standard SAEC offset angle that was much less than 23 degrees, and only offered correct alignment at the inner grooves of an LP. I had them make the arm with 23 degrees offset angle to match "our" alignments and be saleable in the West"......

Allen Wright for the SAEC WE-308 :
..... "I actually don't have a 407/23 as I sold them all way back, I got a mint NIB 308 a couple of years ago and use it - with the cartridges weirdly twisted in the headshells to get the angle correct"

As you can see..........there is no doubt about the general acceptance for the Baerwald IEC standard alignment geometry.

I hope not to fall far from topic, but maybe this is a good opportunity, once the SAEC WE-308 has rundown to torture his users for the last 27 years.

Thus Im wondering if the time has come for Dertonarm to release some knowledge to the rest of us...
But are we ready to accept his "paradox" findings ?
Can we handle any truth beyond the graphic diagrams ?
So far the listening tests are giving credit to him for his new FR64S' alignment geometry & I can't think that he acted randomly without a very good reason behind this !
Is it really just the Offset Angle that determines the chosen geometry ? I doubt.

Thank you for your patience & my apologies for my ignorance.
Dear Geoch: IMHO the alignment geometry alternative we can choose for cartridge/tonearm set up is " independent " in which tonearm we will make the set-up.

Löfgreen, Baerwald, Bauer, Stevenson, Pisha, etc, etc, set up geometry equations are mathematical/abstract " items " that the only tonearm factors that take in count is that the tonearm must be a PIVOTED and its effective lenght and that's all.

If you or any other person ( like the Sansui colaboration you posted. ) thinks in different way this kind of thinking IMHO is only a misunderstood or only a false marketing " tool ".
Goech, all geometry options for set up that exist ( till today ) has its foundation on Löfgren equations that comes from 1938 ( when your SAEC/Graham does not even exist. ) and no one option outperform the Löfgren B one.

Yes, with the SAEC tonearms if we follow the manufacturer set up information with many cartridges it is a pain for the headshell wires set up and that SAEC manufacturer set up advise does not gives any real advantage.

Löfgreen B IEC is very good option and has the best/lower overall distortion. The DIN one gives you a lower inside grooves distortions but with a higher distortions outside the inner grooves: I don't like it, my take is that good tonearm with good cartridges are very good trackers and I prefer lower distortions overall against a tiny lower inside grooves distortions that I'm sure you can't detect because the difference in distoprtion level between IEC and DIN is extremely small.

Anyway, the real subject is IMHO that you can use any geometry equations option it does not matters which tonearm you own.

Nothing impede that you can test Löfgren B or Löfgren A ( that's similar to Baerwald with the same offset angle/overhang. ) or Stevenson set up and decide which set up please you.

Be carefully when doing that because for you can hear the real differences everything reside/foundation in how accurate you made each one geometry option set up. If there are differences on accuracy options set up then the differences you will hear will be because those different inaccuracies levels.

If I was you, with your SAEC or any other pivoted tonearm, my choose will be Löfgren B (IEC. ) but you can choose whatever you want, it's your call.

Regards and enjoy the music,
Raul.
Dear Geoch: That general acceptance on Baerwald is IMHO a wrong way to go, nothing I repeat nothing outperform the overall low distortions ina Löfgren B geometry set up: it does not matters what other people could say or already said it.

These are the parameters for Löfgren B ( IEC ) SAEC 808SX: overhang: 17.729 with an offset angle: 22.914.

Distortion between null points: 0.424% with an average distortion: 0.366%.
Against DIN that has higher distortion figures: 0.469 and 0.376%

Regards and enjoy the music,
Raul.
Dear Geoch, Raul and I agree here to a large extend. I have not "discovered" any "paradox" here. I just questioned the universal used baerwald IEC as I know from personal experience with many tonearms and from a large record collection with many samples from the late 1950ies and 1960ies (i.e. cut close to the inner label...) that Baerwald IEC is not always the best possible.
The fact that it is the most widely used lead to the evolution that it is no longer questioned at all.
It is indisputably the best possible for a 9" tonearm AND for tracking modern records with longer lead out-grooves.
But there are 10", 10.5", 11" and other odd tonearms out there and there are many Mercury SR, DECCA SXL, Impulse, Columbia 6-eye tec. out there.
And Baerwald IEC is not ideal for them.
The records you play do have an important role here. If the majority of them is cut following and taking advantage of the wide area of DIN, then IEC is sub-optimal and an alignment following DIN might be better suited.
And no - an offset angle does not determine a tonearm's geometry. But if your cantilever when aligned is far off line with the offset of your tonearm, then that should tell you something .....

I did long research when designing the UNI-Protractor and I offer a wide range of universal as well as individual templates for good reason - and certainly not just to fill the books....;-) ...
Cheers,
D.