Uni-Protractor Set tonearm alignment

I think Syntax has taken shots of Dertonarm's first production unit.
The first run won't ship till March and my one will be in the first shipment.
I think it looks beautiful and knowing Daniel, I'm sure it will also work as promised.
If it does.......it will be what we've all been waiting for?

Dear Daniel,
Interesting comments on arms with knife-edge bearings?
The SAEC arms with double knife-edge bearings enjoy quite an enviable reputation amongst the 'vintage' fraternity with Thuchan even ranking the 12" versions competitive with the FR series tonearms?

I wonder if you might expand on the weaknesses you find in this solution.......especially since I have a new addition to my arm collection arriving shortly.......namely an SAEC WE-308?
Cheers
Henry

Dear Daniel,
Interesting?
How about unipivots?
Do they like low compliance cartridges in your opinion?
Cheers
Henry

Interesting comments on changing the Effective Length input on the arm's set-up geometry?
Those with a Fidelity Research FR-64s tonearm will know that the manufacturer's recommended spindle to pivot distance is 230mm.
This is precisely the figure I used when setting mine using Baerwald geometry.
It was only when I read Dertonearm's statement that Fidelity Research "got it wrong!" that I changed the spindle to pivot distance to Dertonearm's recommended 231.5mm with an overhang of 14.5mm.
Instantly I heard a difference across the entire presentation?
More relaxed, more focused and somehow 'sweeter'?
How could this be? Was it the 'placebo' effect?
As Raul claims that our ears could not hear the differences in distortions that are indeed quite small between different geometries, why am I hearing a perceived improvement in presentation?
Shouldn't I, at the very most, only hear a difference in distortion at either the beginning or end of a record?
Perhaps Daniel could explain to me what it is I am hearing and why the change of arm geometry has caused this?

Raul,
When I changed to the 231.5mm spindle to pivot dimension and 14.5mm overhang, I changed the off-set angle to compensate correctly at the null points.

When I first tried to actually use the UNIprotractor, I wished I hadn’t have volunteered to do a review.
No matter how hard I tried, I couldn’t see the stylus?!

The package from Germany arrived many days ago and at first I was slightly disappointed at the appearance of this plain brown cardboard box.
Surely a white or black box with some unique graphics was warranted to encase the high-tech machine-like tool within?
Of course that would have increased the costs and Daniel did not at first know, how many of these ‘machines’ he would sell?

Once opened, the contents were convincingly revealed to be well packaged and a few surprises, such as an LED high-powered lamp and a pair of soft white gloves were included.
Prior to its arrival, Daniel had Emailed the coloured Instruction Manual together with the appropriate micrometer settings for 5 of my 6 arms and let me say that with the exception of the Copperhead, these instructions are better than those which came with all my tonearms.

But back to the turntable.
I had easily assembled the UNIprotractor as detailed in the Manual, and had it positioned on the nude Victor TT-81 with the Fidelity Research FR-64s tonearm as the first ‘patient’.
This was not a fair test admittedly, for the ‘Dertonarm’ recommended geometry for the FR-64s does not follow Baerwald or Lofgren and the spindle to pivot distance recommended by the manufacturer, is not followed by the UNIprotractor.
I had already adjusted my spindle to pivot distance for the arm to be 231.5mm instead of 230mm and had aligned it via the Feikert protractor by utilising its ‘overhang’ alignment rather than its Baerwald alignment. This also required a ‘twist’ to the tracking angle but I didn’t have the correct ‘null points’ to accurately gauge this angle so I knew my set-up was inaccurate.
The cartridge was a MM favourite of mine……the Signet TK-7e mounted in the FR-3 headshell and for the life of me, I couldn’t see the stylus, head-on, through the magnifier.
After developing mild backpain crouching for over an hour, I decided to switch off the lights, have a coffee and a well-earned rest.
During this interlude, I pondered whether Dertonarm had erred in his design by using only modern LOMC cartridges rather than my preferred vintage MMs which had their stylus tips generally tucked well back from the fronts of the cartridges.
Had I just purchased a ‘white elephant’ I wondered as I gazed at the trees framed against a deepening blue sky?

After an hour, I returned to the turntable, switched on the LED lamp and peered once again through the magnifier.
Could it be? Was that it? A stylus tip?
I grabbed my hand-held magnifier and held it behind the fixed magnifier and there I saw it…….a clear stylus and its black cantilevered shaft framed against the mirrored gridlines of the UNIprotractor :-)
Most new tonearms are somewhat intimidating on first ‘set-up’ but once familiar, they become easier and eventually simple to adjust.
The same must be said for alignment tools.
The Feikert was initially difficult and is now child’s play as is Yip’s MintTractor and the WallyTractor.
Once I knew what I was looking at and for, it became easier and easier to use the UNI protractor until by the fifth arm, I was laughing.

The Signet TK-7e was ‘out’ by nearly 2mm and its tracking angle was also off. Easily fixed using the UNI.
My previous defacto set-up tool of choice has been the Feikert which is a one-point devise like the UNI. Whilst I use it to set spindle to pivot and overhang (based on Baerwald), I like to use the Mint to adjust the correct tracking angle at the Null points because it is so easy to see compared to all the other devices I have.
The Feikert came with my DaVinci 12” Ref Grandezza tonearm and whilst one face of the white Tractor Disc is marked as a ‘Universal’ template, the other face is dedicated solely to the DaVinci.
As such, you would expect it to be ultra accurate and so it was. The UNItractor proved that the DaVinci was as good as you can get.
With the other arms and various cartridges, the UNI showed some to be ALMOST perfect, whilst others required adjustment. None was perfect like the DaVinci, and having the UNItractor prove this fact, I trust it implicitly for the other arms.

So is the UNItractor worth its price? If you have several arms and/or interchangeable headshells equipped with multiple cartridges, I would say yes.
If you have only one arm and want the most accurate tool available to align an arm/cartridge then again I would say yes.
Is the UNItractor perfect? No, I think it can be improved…..and quite easily.
Firstly, being a one-point device rather than a two-point arc protractor, the spindle to pivot dimension is critical.
There seems little point IMO, to have the accuracy and tight tolerances of the UNI if you can be 2mm-5mm ‘out’ in your spindle to pivot distance?
The best device I have seen for measuring this dimension, is the adjustable Feikert aluminium sliding beam and locator. This is rigid and super accurate but what does the UNI provide?……a floppy steel rule. There is simply no way that anyone can come close to accuracy with this means other than by fluking it. And this is so silly because the UNItractor already has a device which is nearly as good as the Feikert. The locating device which locks onto the spindle and hovers over the tonearm pivot could easily have a scale on its base which can measure the spindle to pivot dimension. I know that Daniel is soon coming out with a proper measuring device but this IMO is unnecessary.

Another ‘improvement’ I could suggest is that the mirrored templates which ‘click’ into the protractor for each different arm, should be a ‘frosted’ mirror like the Mint instead of the full mirror which is more difficult IMO to see clearly.
A further suggestion I have is that the selected arm geometry should be engraved on these mirrored templates. At present one does not know if one is setting the arm for Lofgren A, B, Stevensen or something else as Daniel ‘pre-selects’ what he considers is best for each arm. In some cases that is simply the arm manufacturer’s recommended geometry so that for my Grace 940G and Micro Seiki MA-505S which both have the same effective length and overhang, Daniel supplies two separate templates.

Apart from these easily incorporated ‘improvements’, I have nothing but admiration for Dertonarm’s UNItractor.
A serious device for the serious analogue audiophile.
UNIprotractor

Thanks Jazzgene and Downunder,
It's interesting to read all the first impressions as they begin to trickle in?
It seems there are some who like the full mirror whilst others may prefer a 'frosted' mirror? Personally, I never understood how to correctly use the full mirror in a parallax reflected mode so perhaps that would be an advantage?
As Daniel is now finding.......you can't satisfy everyone?!
Thuchan, who always strives for the best possible solutions, has devised a perfect way to utilise the supplied steel rule but his description is not as good as his photo of the solution (a picture is worth.........). Hopefully Eckart, you can find a way to post your picture?

I have been rethinking the steel rule comments and in Daniel's defense, there are many more turntables with 'fixed' tonearms than those accommodating changeable tonearms. I myself lived for 25 years with a Rega Planar 3 with a 'fixed' Hadcock GH228 so why would I worry about Spindle to Pivot dimension?
Of course in those days before the Internet Forums, I didn't even appreciate the importance of critical alignment?
And those of us who in fact do have adjustable tonearm mounting devices, would certainly already have a Spindle to Pivot measuring device already.
So I can understand Dertonarm's thinking here although something tells me that whilst the UNIprotractor 'arm' is not centred on the Spindle, there might be some mathematical formula which, when the micrometer is wound down to its minimum position, could still be used to check Spindle to Pivot dimensions?
Perhaps Daniel could consult with a mathematician about this?

This leads me to another question about the UNIprotractor.........if someone has a turntable with a fixed arm which had been incorrectly positioned by the Dealer or Manufacturer by say 2-3mm (which is very easy to occur), what effect does that have on the accuracy of the UNIprotractor?

Another question which gives me even more nightmares?.........if each arm is set according to a different geometry/alignment, how do those with cartridges mounted in interchangeable headshells swap those headshells between arms?
I certainly don't want to have to align each cartridge when I change headshells and then change it again on another one?
Life is for 'listening'.......isn't it?

It does beg the question, though, of why one would need to know the mounting distance, as the Dennesen principle allows correct alignment with any existing and unknown mounting distance. If the distance has been set wrongly for a particular arm, this would be corrected (for a slotted headshell) by adjusting the effective length and cartridge offset (assuming enough adjustment) to match the null on the protractor.

Thanks for that explanation John.
Then the Feikert alignment tool works on a different principle where Spindle to Pivot distance and Overhang are critical to achieving correct geometry? Is that correct?

Dear Daniel and John,
I accept that the majority of tonearms in use today are 'fixed' to their turntables and cannot be adjusted.
The accuracy of the positioning of these tonearms vis-a-vis the spindle to pivot distance is often not the greatest and I appreciate that the UNIprotractor achieves the correct cartridge alignment regardless of the accuracy of the tonearm placement.
Having said that however, I believe that the cost of the UNIprotractor can best be amortized by someone possessing multiple arms and often in such a situation, some of those tonearms will have removable headshells?
If each tonearm is 'inaccurately' positioned in terms of S to P distance, the swapping of headshells+cartridges between arms, will result in multiple accumulating errors......no?
Additionally, if one is using fixed headshell/cartridge combinations such as the FR-7 series or some EMTs, adjustments within the headshell/cartridge are simply not possible and correct spindle to pivot dimension is essential to extract the best performance n'est pas?
It is obviously ideal to have the tonearm set at the correct S to P dimension and an accurate method for achieving this is desirable.