I enjoyed your review.
For me, I want to do a better job finding the center of the pivot on the 10.5i arm with the Uni-Pro. Perhaps the reticule can be of a different color? Since it is white, it is a bit tough to see against the silver of the 10.5i arm. This issue is not limited to Uni-Pro. Feickert and Clearaudio also has this issue. The center rod is too skinny for the center hole of the 10.5i arm pivot. At least the Uni-Pro provides a reticule. |
Dear Jazzgene, good point here ! On black colored finish tonearms the UNI-Pro's reticle will be best as it is, but I will pick up your suggestion and will have a batch of reticles w/black hairlines made in 2nd production run. I will provide a reticle with black hairline once the 2nd production run is ready to ship, which will be end first week May.
Cheers,
D. |
I am very happy that you can change the color of the reticule. Thanks. Great customer service. Looking forward to getting it. |
Here is my review of the Uni-Pro. Received it in great shape. Well packed and bomb proof. I liked how you packed the unit. I did notice a few freebies such as the ruler and the light?
Upon setup, I noticed a few things that could be improved.
1. the center pin is a little short for my liking as my Dynavector has a lower pivot piont. I think a longer pin would work much better and would not hurt the design.
2. like Jazzgene said, The lines on the centering device is very difficult to see on lighter/shiny tonearms especially the FR66s and my DV507. I believe should the lines be anothter colour instead of white would be much easier to see.
3. Numeric markings on the acrylic arm like the Feikert would be a bonus.
Now to the strong points.
This thing is built like all German made stuff. Serious, tough and the word precision written all over it. Looking into the magfier proved an easy task on this system as it has a large enough lens.
Upon checking my setup, I noticed my alignment off by a little. Correcting it via the Uni proved easy enough.
Now to the sound. The setup (DV507) after using the Uni was more solid and focussed. It also proved itself as after the adjustment as there was slightly less surface noise (quieter) and less grain in the music.
So far this is the first tonearm I have setup with the Uni. Will do my other tonearm when I get time this weekend.
Now to the milloin dollar question.....Is it worth $800? I will leave it up to you. If you are like me who regularly sets up turntables, It is definitely worth it's asking price. Also if you own a resonably priced analog rig and plan to go deeper into analog, You owe it to yourself to get one of this UNI's and setup your own turntable instead of getting someone to do it for you. |
My Uni-Protractor had just arrived. Although I am not yet in position to put to use, may I offer a quick initial impression. As a watchmaker for many years I developed an utmost appreciation of finely crafted precision tooling. Overall, I am very impressed. The price outlay is very small compared to my, or many others, TT setups. I feel very good costumer service here, and that this is just a beginning for Dertonarm. |
Nice reviews Jazz, Halcro & Genesis. I received mine on Thursday. I said I would be honest and open, so here it is. Halcro, I especially liked your photo's and you gave me the rather obvious position in hindsight to place the led light on the inside of the tonearm. First up, the packing, quality and german engineering excellence of the package is there for anyone to see. First class. You actually feel that you are purchasing something of class. Issues for me first. Giving out a bendy small ruler for P2S measurement is a bit of a joke IMO, regardless of .5mm accuracy. You will be more than .5mm out on the P2S measurement given the inadequacy of the ruler. Given the entry price, a better tool should have been provided in the package like with the cheaper direct competitor, the Fiekert. It has an excellent P2S measurement device as part of the alignment tool. This may be my oversight, however when looking initially at the photo's and given that the alignment devices in competition are Fiekert I thought the positioning arm was also the P2S measure. Given P2S is measure is such a critical part of any alignment tool, that one was not provided is poor IMO. back to the review the instructions in the manual are very detailed and straight forward - excellent This device will take you longer than the Mint or Feikert, however you IMO get much better precision than the Feikert. The Feikert is poor with its generally fat lines painted onto steel compared to the Uni-tractor. The Mint has always been a poor cousin to the Wally tractor and the uni tractor with its lazer etching is a lot better than the Mint's lines under the mirror approach. It was easier to align the stylus point onto the exact lazer dot on the uni template compared to either Mint or Feikert. That is the beauty about the lazer etching. I, like the others struggled a little bit with the two etched lines on either side of the middle line, in how they curve slightly due to the magnification. like anything, after a bit of practice it got easier. Once that was done, you were complete. two points vs one point. Frankly, with the Mint. If you aligned the initial null point perfectly, I always found the 2nd one lined up as well. So the Uni-tractor having only one meassure point is no big deal, you just need to concentrate on getting it correct up front. The Azimuth tool was cook and very good to use next to the tonearm to see how level the tonearm was. - non standard uni-templates. I guess a lot of people are interested in the specific aligment templates. to quote Daniel the EA-3 template is based on the EA-3's geometry, but a bit
"optimized" by myself - so kind of "my brew".
- same for Graham and Ortofon - very slight corrections, but better
distortion figures than manufacturer's specs. I used the Exclusive EA-3/10 alignment template to compare with the Stevenson alignment from Mint. Yes, I know, not really a fair comparison. The Stevenson vs Stevenson will come later. I buy mostly modern LP's but many have music right to the inside label. I much prefer Stevenson/VPI type alignment than L or B. Mainly due to the fact that the inner 3rd of any LP(which is getting smaller and smaller with each revolution)to my ears has the most obvious distortion compared to the rest of the LP. Overall the slight increase in brightness on the 1st 3rd is more than compensated with the better sound of the last 3rd with Stevenson. Right, my listening bias are out of the way. The EA-3 alignment was more relaxed in the first 3rd vs Stevenson and as good ads B or L from memory. It was better sounding than either B or L in the last 3rd to my ears. Not quite as good as Stevenson, but overall something I can live with. I'll go back to Stevenson in a couple of weeks. My Mint tractors will be soon for sale on audiogon. The Feikert I am afraid cannot be sold ATM as detailed above. I believe the adequate P2S tool should be part of the Uni-Tractor price given its importance for correct alignment, not offered as it seems to be next week as an additional extra. I would be interested if anyone else shares my view on this or I am out of line. Overrall a 1st class product is the Uni-tractor and oozes quality. |
I think Daniel added the ruler as a "estimate" tool and not for a precise measurement. If you look at the positioning arm, it does not go to the spindle so it can't give P2S measurement without a complete re-design.
I believe if you are very careful, you can get a very precise measurement of P2S with the ruler supplied, though. Use some CD cases to lift the ruler so it is completely parallel to the platter. Look at the ruler directly from above as well. |
Downunder, I fell into the same trap as you, and you are completely right: The Feickert provides a comfortable distance measurement.
What I did: I fixed Dertonarms scale tool on the Dennessen, putting the black middle round over the spindle as a horizontal bases, and put the Azimuth transparent block on top running it against the scale (see last image on my page).
I am now absolutely precise on the distance and in the next step I do use the UNI-Protractor.
Of course you are right it would be fine to have it within one tool. maybe Dertonarm will consider a UNI-Protractor v2 combininig these capabilities.
Best & Fun Only - Thuchan |
Dear Halcro,
After further engagement with the Uni-Protractor I can share your experiences. Especially regarding the "frosted mirror design". It is sometimes very difficult to hit the point. If I am using a lamp into the direction of the needle it helps a little to find the exact location.
regarding the P2S measurement I have made a suggestion in my answer to Downunder. At the moment I do think a two step approach, P2S measurement, then using the UNI , makes the most sense.
It is not a 9000 Dollar arm which comes in a 200 Dollar box, but you understand that this tool is designed for other purposes. Nevertheless I wish i had a wooden box to put in the fully build up Uni-Protractor just to take it out for usage when neccessary.
Best & Fun Only - Thuchan |
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? |
Dear Albert,
you may get some comfort in changing headshells if you are using those ones with a fixed cart like the Fidelity Research FR-7 series in the same arm. This is among other reasons why I have one FR-66s on each Micro. Also the EMT JSD 6 Jubilee which I regard as a best buy for its quality and its wonderful sound provides a fixed solution.
The Ortofon RMA 309 allows changing EMT & Ortofon carts "nearly on the fly" not changing anything even not the weight in most cases.
Bu to be honest the real fun we have when "working on our arms and carts". Otherwise we cannot use our alignment tools resp. the Uni-Pro.
I also wonder why it shouldn't be possible to move the Uni-Pros arm to the middle as you describe it. |
maybe the simplest solution is to print an exact scale meter on the Uni-Pros arm and supply an extra transparent block using parallel lines and matching the layout of the Uni-Pro just at the spindle site . You may then put the extra block over the black round spindle positioning it exactly over the middle of the spindle and facing it towards the scale meter as I have tried with my Dennessen approach. You are then able to read the distance easily. No more Feickert, no more Dennessen necessary. Dertonearm may provide a modified Uni-Pro arm and the block as a substitution package.
Best & Fun Only - Thuchan |
I was always thinking about how to combine my measurement suggestion with the Dennesson and also the alignment by the Uni-Pro. Therefore only using one tool!!! For me the quest is over! You may see the result on my page (last image)
Best & Precision Only - Thuchan |
Dear Thuchan, dear Downunder, originally I designed the UNI-Protractor as a tonearm alignment instrument. Measuring P2S is a matter of tonearm set-up and should be done prior to any alignment (usually you have to drill a hole in an armboard and so the mounting distance is kind of "pre-determined" before starting any alignment).
That's why P2S-measuring wasn't include din it's design. I now realize, that including the stainless steel metric ruler kind of woke up the wolves....
In any case - I will come up with an add-on to enable precise P2S measurement with the UNI-Protractor soon. This will NOT need any alternation to be done to UNI-Protractor and will come with a precise manual and installation instruction.
It will be a 5-minute plug'n'play device.
However - please accept my initial concept, that in my - sometimes strange and weird - mind, P2S was not an integral feature nor request in an alignment instrument for tonearms.
I still think that P2S is a part of tonearm set-up.
But - I will address it due to "public demand" ...;^) ....
Cheers,
D. |
Dear Dertonarm,
do you have a launching schedule in mind?
Best & Fun Only - Thuchan |
Dear Thuchan, yes I have a schedule. The UNI-P2S will now come as a tool which can easily be incorporated with the UNI-Protractor (without any alternation !!) as well as stand alone as a precision mounting distance measurement instrument for it's own sake.
It will be introduced next week (i.e. first week of May ).
Cheers,
D. |
Dertonarm,
I apologize but I think I may have missed something in your thread. Is the P2S for measuring the pivot-to-spindle distance or the pivot-to-stylus distance (overhang)? Could your device be used to measure either?
I am considering a separate dedicated arm pod for mounting an additional arm. I would think that your UNI-P2S, if pivot-to-spindle, would be indispensable for this purpose.
Keep up the good work. I'm beginning to wonder what other devices you have up your sleeve. All this for improving analog playback just as I read from Raul (in another analog thread) that he thinks the best digital can now compete and even surpass good analog. (Sorry if that is a bit controversial to introduce in this thread) I think it is all about tiny improvements in accuracy adding up to real sonic gains in either medium. |
Dear Peterayer, there is an overhang gauge coming with the UNI-Protractor set to measure direct spindle to stylus distance (overhang).
The UNI-P2S will integrate into the UNI-Protractor as well as can be used as a stand-alone-device and allows precise spindle-to-pivot measurement.
Cheers,
D. |
Peterayer, You may be interested in what I deed. My Kuzma
Stabi Ref. has just one armbase but because I own Basis
Exclusive phono-pre with two separate pres I wanted an second tonearm to put next to the TT. Both the arm pod and the tonearm are made for me by the Reed (www.reed.lt).
Thy produce those armpods on order. Ie according to your ownspecifications. On their web site you can see 'my' solution (by feedback) and the arm pod by the accessory.
Regards, |
Dear Dertonearm,
I have not been following this thread, but as you know, I have a Uni on order. Please tell me, can the basic Uni that I will be receiving, without any of the extra and extra-cost items you are about to introduce, accurately cite the location of the tonearm pivot using the spindle as a reference? That's how I use my Dennesen and partly why I bought the Uni. Thanks. |
Dear Lewm, and this is exactly what the UNI-Protractor does ... ;-) ...
Seriously, the UNI-Protractor works in exactly the very same way as the Dennesen, - which I have worked with for 25 years.
This discussion started by the reviews of the uNI-Pro by Downunder and Halcro was about the actual measurement of the spindle to pivot (i.e. mounting distance or P2S) distance which is not incorporated into the UNI-Protractor's design.
In the UNI-Protractor's set a stainless steel metric ruler with 0.5mm scale was included as a handy tool for the owner to check the P2S if one is curious. This however raised the question why it wasn't incorporated into the positioning arm - just like in several other templates on the market. This of course can't be an option due to geometrical reasons.
Originally I had in mind a super-precise P2S measurement device as a stand alone tool. To me mounting distance was rather a different topic as alignment and a pre-determined condition on most turntables anyway. As the UNI-Pro - just as the Dennesen to Baerwald IEC (Löfgren A IEC) - aligns to a certain geometry independently of the mounting distance, I originally saw no need for measuring the mounting distance (P2S). Some owners of the UNI-Pro did however find this to be the one shortcoming and thus I want to address the issue with an optional P2S-tool which can be incorporated into the UNI-Pro at wish.
It will now come as a relatively inexpensive add-on which can also be used as a stand alone instrument.
An option like the UNI-Scope - not mandatory at all for perfect function nor alignment with the UNI-Pro.
Cheers,
D. |
Finally had time to try Dertonarm's VPI template. It is very close the VPI jig. The stylus hit the stylus mark on the template exactly. I saw it was canted slightly with the stylus end of the cantilever closer to the spindle. I made the adjustment and am listening now. The cartridge is the Grado Statement1 on a VPI 10.5i arm. The LP is John McLaughlin's Extrapolation.
Compared to the VPI, the music sounds more open and the individual instrument's are more clear in the stereo mix.
I don't have any idea what Daniel's VPI template is based on but it sure sounds good. This is the setup I will be using with my VPI table. Thanks, Daniel. The only wish I have is to have an easier way to find the exact center of the pivot. I found the regular pin easier to "see" the center of the pivot than the reticule.
Overall, I am quite happy with the Uni-Pro. The led light is very useful and the setup makes it very easy to see the cantilever. |
Dear Jazzgene, thank you for your impressions.
In the 2nd production run we will produce too a different version of the round reticle with black cross-hairs.
It will be much easier to read when spotting silver colored bearing houses.
This is available as an option side by side with the white engraved reticle that come with the UNI-Protractor ( which in contrary is easier to read on black tonearms).
Cheers,
D. |
As an aside: Halcro, you asked (16th April): 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? I don't know how the device works, how it differs from the Dennesen, or what the various fine adjustment features are, but presumably they allow the device to be set up for Baerwald IEC nulls, (and whatever other nulls are supplied). If the principle is Dennesen, which it appears to be, then arm mounting distance (pivot to spindle distance) can be obtained by finding two dimensions: First: The distance to the arm pivot as measured along the axis of the perspex arm from the point where the null radius crosses it. Call this X. Second: The distance from the centre of the spindle along the null radius to the centre line of the perspex arm that terminates on the arm pivot. This distance varies depending on the alignment, and must adjust for each, but you don't have to measure it if the device can be set for Baerwald IEC as it is given by: Outer null minus Inner null, then divide by 2, Call this Y. (For Baerwald IEC this is 27.45. If the device is set for another alignment, then the same calculation applies with the appropriate nulls.) This gives a right angled triangle, so the mounting distance is given by: the square root of: X squared plus Y squared. This applies to the Dennesen also, of course, but only for the Baerwald alignment for which it is set up, unless modified. The accuracy of the method depends on how well you can measure the distance along the perspex arm to the pivot. 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. . |
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? |
Good point here. That's the reason for the micrometer driven linear stage carrying the positioning arm - it sets "Y" precisely for whatever null point the specific UNI-template sets.
My initial thoughts when designing the UNI-Pro were similar.
If a phono protractor really is universal, it must automatically align regardless of the given mounting distance.
In most cases the tonearm is already mounted when one starts to align the tonearm/cartridge. Then there are a good many situations where the P2S simply can't be altered by the user (pre-drilled mounting hole, fixed armboards/plinth).
The UNI-Pro does follow the smart idea of Francis Dennesen and adapts to whatever P2S a given tonearm is mounted.
Setting the mounting distance is done before aligning the tonearm. It is a "conditio" already set before starting the alignment.
If however the user does wish to align the given tonearm exactly to the geometry (especially the offset angle) the tonearm was designed with, then knowing the P2S and setting it precisely (IF possible ...) is important.
Important only if one wants to avoid an additional breakdown torque and thus another source for skating force in a pivot tonearm with a fixed offset cartridge mounting.
With tonarms like the Schroeder, Reed or Talea however we won't run into this problem at all.
Cheers,
D. |
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. |
I tried the Uni-Pro on my Thorens TD-316. I love this simple table and is my 1st table I bought as a kid. Got it new in the mid 80's.
I chose the Baerwarld IEC for this table which comes with the TP-21 arm. I used Benz Micro MC20E2 cartridge.
I had to level the spring suspension a bit after placing the Uni-Pro on the platter. No big deal. The cartridge had to be scooted all the way to the front of the headshell in order for the stylus to hit the point precisely. The Uni-Pro makes sighting the cantilever a simple procedure.
Listening to some Keith Jarrett LPs and I have to say, this modest table does hold quite well against my main table which costs much much more. It's been running just like new for close to 30 years with just a belt swap. Including several home moves! Too bad Thorens ain't what it used to be. |
Halcro
I haven't used it, but I'm sure you are correct in assuming a different principle for the Feickert. If it has the facility to set or measure mounting distance, it is because it uses arcs which have to be referenced to a known pivot point.
You are correct in saying that headshell type cartridges having no facility for adjustment need to have the effective length of the arm with the cartridge fitted known or measured. Also the true cartridge offset angle (which will depend on the arm/cartridge combination) also known or measured. Then an appropriate mounting distance can be calculated, and precisely set.
Alternatively, using an arm with a known alignment, you can use (if it has the same alignment) a two point protractor to set up. By sliding the base the offset will be given automatically. Swapping different kinds of these cartridges would depend on them having the same headshell mounting collar to stylus distance.
You are also right in saying that swapping headshells could be problematic. It looks to me that swapping headshells between arms would require them to be set up initially with one headshell/ cartridge combination which remained set once the first arm was done, and which was then used to set the remaining arms with adjustment achieved at the bases of the others, assuming they were different arms.
The alignment chosen would have to also be the same for each set up, irrespective of the arm design, but the arms could be different lengths. Then any cartridge/ headshell combination could be set up to suit these alignments without moving the bases. This would depend on the headshells having slots, though the initial headshell could have holes as long as the arm used was designed to the chosen alignment.
I think that covers most of the difficulties..... please feel free to point out a simpler way, any mistakes or anything I've overlooked.
John
.
|
Dear Halcro: I don't think you noted yet. Several of my hedashell removable tonearms design have the manufacturer overhang spec at 15mm, I choosed on porpose due so many tests cartridge/tonearm combinations I have. This similar overhang characteristic help me to mount with almost none change any cartridge in any of those tonearms.
Yes, this is not exactly what you are talking about but an idea that could help.
Btw, now that you and other people are so in " deep " about cartridge/tonearm set up through accurate protractors seems to me adequate for you and every one that want to " explore " and learn on the subject to make a simple ( no money need it.! ) experiment:
- in one or two of your cartridge/tonearm combinations move the cartridge 1mm forward ( no protractor need it. ) and mantain the same cartrridge/headshell offset angle. After re-set the VTF and VTA/SRA and if you want azymuth and antiskate ( not need it for the experiment but if you want to be more " even " with today set-up. ) push the playback " button " and listen for a while.
After that and if you have the time and patience move the cartridge an additional 1mm forward and the same process but moving the cartridge 1mm and 2mm rearward.
Compare what you listened on those four different set ups against each to other and against what you are listening in your rigth now set ups.
IMHO this is a un-expected ( because the quality performance ) experiences where we could learn what is happening down " there ", I mean on playback against no-play status.
All of you that decide to " explore " in this " jungle " will be appreciated what you experienced.
Thank you in advance.
Regrads and enjoy the music,
Raul. |
Dear Halcro: My mistake. That 15mm on overhang is not what help me but the distance between the cartridge stylus and the rear part on the headshell that if I remember is 50mm on some of my tonearms.
Raul. |
Jazzgene, 'to bad Thorens ain't what it used to be'. I agree but there are many of those 'old one' second hand still demonstrating the value of simplicity in design: good platter, good bearing and an simple motor. Despite of
this fact the Uni-Pro on them looks to me like a King on
a donkey.
Regards, |
Dertonarm: You said: If a phono protractor really is universal, it must automatically align regardless of the given mounting distance. I would agree with you in that, but I would disagree with you when you say that Setting the mounting distance is done before aligning the tonearm. It is a "conditio" already set before starting the alignment. This is only necessary when using a protractor which requires it - like yours - because, as you say, The UNI-Pro does follow the smart idea of Francis Dennesen and adapts to whatever P2S a given tonearm is mounted. As is the case with the Dennesen, arms with adjustable bases and fixed headshell mounts are awkward for your protractor. So it can´t really be called universal, as it only caters for arms with adjustment for effective length and offset at the headshell. In most cases the tonearm is already mounted when one starts to align the tonearm/cartridge All arms are "mounted" prior to alignment, but, as you are aware, not all arms have the pivot to spindle distance fixed at a specific measurement, but have the facility to adjust this, as in any arm on a pod or adjustable arm board, or the SME, and arms like it. It could be argued that a more universal version of the Dennesen would have adapted it to allow its use with arms such as these, as well as with different alignments. . |
Raul,
Could you please elaborate on this? I don't understand what you are trying to do by moving the cartridge forward or backward. Are you asking us to listen for different amounts of distortion from a cartridge that is no longer aligned properly? Thanks. |
Dertonarm: you said If however the user does wish to align the given tonearm exactly to the geometry (especially the offset angle) the tonearm was designed with, then knowing the P2S and setting it precisely (IF possible ...) is important.
Important only if one wants to avoid an additional breakdown torque and thus another source for skating force in a pivot tonearm with a fixed offset cartridge mounting.
With tonarms like the Schroeder, Reed or Talea however we won't run into this problem at all. Didn´t you suggest starting an antiskate thread? But since you have brought the subject up, in what way do the Reed, Talea and Schroeder differ from other arms? The Talea and Schroeder appear to have a facility to alter the effective length,(as does any other arm with a slotted or movable headshell) and they have a facility to alter the headshell angle. What is the difference between this and altering the angle in a normal headshell? The Reed has a normal slotted headshell except for the model with its little azimuth adjusting device. What´s the difference? I would honestly like to know. And I am intrigued to know what are these mysterious additional breakdown torques which the above arms don´t have. Unless you can explain where else it comes from, the only torque acting to rotate the arm inwards is generated by forces acting on the stylus in reaction to downforce and friction. More downforce, more friction; more friction, more inwards torque. No downforce, no friction.; no friction, no torque. Using more downforce doesn´t make the inwards force disappear, just that the force acting downwards is enough to allow the stylus to track without distorting. The imbalance of forces on inner and outer groove walls hasn´t gone. John . |
Dear John_gordon, you don't really want me to tell you what additional breakdown torque is and why it does of course influence the skating force.
If you think skating force is just a phenomenon of friction and downforce - fine, certainly no problem with me.
If you muse about the model and draw yourself a good and precise force vector model of a pivot tonearm, you'll figure out.
I did suggest starting a "antiskating thread" - I didn't say I want to start it nor did I say I want to participate in it.
I have no questions regarding skating force in tonearms.
Regarding the UNI-Protractor and it's "universal" use.
Apparently you haven't worked with it so far and haven't understand it's principle either. Otherwise none of the comments in your last two posts would have been made.
You won't find a pivot tonearm on this planet which you can't align with the UNI-Protractor to best possible performance and any desired tangential curve.
If you think you can do better - go ahead design it.
So far your comments have shown little more than poor judgement, a fairly high aggression and very little understanding of the subject.
I welcome your attempt to put your name on the wall again and to prepare the road for yourself for a soon-to-be return to the audio market.
No problem with me - as far as I am concerned you are certainly welcome.
I might react to a post by you from time to time only, but so far very few actually did ask for an answer or a comment. Most were simply lacking content and seriousness. |
Dear Peterayer: Please forgeret about distortions for a moment and suppose that you made ( for whatever reason, never mind here. ) a " mistake " and mounted a cartridge 1mm-2mm forward/rearward of what an accurate protarctor asked.
As you said it you will heard/hear a cartridge that was not aligned properly and this is the subject of this simple " experiment ".
What could you listen or find out? well that's what this test will tell you.
Other than that non-properly alignment nothing that you share with us can have a " negative " argument by any of us. The important subject is what you heard: what you like it, what you don't like it, if you could live with these trade-offs and what do you thing overall against the properly alignment.
IMHO this kind of tests are interesting ones and I have to say that by " accident " ( my errors. ) I heard many times cartridges that were mounted with no properly alignment. I will share my experiences about along yours.
Regards and enjoy the music,
Raul. |
Thanks Raul. I think I understand now. Unfortunately, it takes a fair amount of effort and time to move my TT to properly realign the cartridge after doing such an experiment. I'm presently satisfied with the sound, so I'd rather not mess with it now. I may try it at some later time. I'm sure I could learn something as you suggest. |
Dear Peterayer: That is only an " exercise " that you could do it when appropriate to you.
Regrads and enjoy the music,
Raul. |
Dear Dertonarm.
Spring rain kept me from chores so I did some reading on Agon looking to learn. I read through this Uni thread from the start and came across a post you made on March 11 that is puzzling to me.
Specifically you said.
the linear tracking tonearms - in any incarnation we have seen so far from Rabco, Denessen, Goldmund, Versa Dynamics, Air Tangent, Eminent, Forsell et al -displayed mechanical issues, periphery problems and stability problems which did always crippled their undisputed tangential advantage.
Most audiophiles who ever ventured into tangential tonearms later moved to tonearms with 11" or more effective length to approach kind of "best of both worlds".
I have had all the above named tangential tonearms in most all their incarnations in my system in the past 30+ years.
Wow quite a statement. Two questions.
1) Can you tell me who we is when u say "in any incarnation we have seen" ? Is that an audiophile club?
2)
I have owned the ET 2.0 and now 2.5 arms for the past 5 years so your statement caused me some despair. Is there an unknown problem I am not aware about? Would you please be so kind to enlighten me for the Eminent Technology arm specifically that you owned - about the stability, mechanical, etc
problems you had.
I found alignment tools provided with these linear arms get you to about 75% of their potential. The rest is trial error tweaking by ear. Personal discussions with Mr. Thigpen have confirmed this. You need to experiment and try different settings. See what u like / dislike. Once past the initial tool settings it is all FEEL, ADJUST, LISTEN. Definitely not plug and play but once set up you can forget about it without issues I have found.
All problems I came across in my earlier days with the ET arm, and in talking with other folks about linear tracking arms in general - other than pump/air problems easily fixed - have always been related to actual user errors and the lack of "total knowledge" about the arms and the way they work thus leading to improper setup. After 5 years I am still learning about my ET arms and how they work.
I look forward to hearing back from you when it is convenient on "your ET specific problems" as you say u owned the ET. You did not say whether it was the 2 or 2.5 version.
Lastly does the Uni package contain any tools that would be useful for lining up linear tracking arms ?
Thank you. Chris |
Dertonarm Allow me to return the rattle that you have thrown from the pram: You said: you don't really want me to tell you what additional breakdown torque is and why it does of course influence the skating force. If I didn´t wish to know I wouldn´t have asked. I´m always willing to learn something new and if you have something new to say, I´m willing to hear it. It is just that you seem unwilling or afraid to actually say anything at all - commercial reasons? You said If you think skating force is just a phenomenon of friction and downforce - fine, certainly no problem with me. I didn´t say that. A neat attempt at misrepresentation. You said If you muse about the model and draw yourself a good and precise force vector model of a pivot tonearm, you'll figure out. I have done. A long time ago. And since then I have re-considered my original thoughts and am willing to continue doing so in the light of new facts. You said: I did suggest starting a "antiskating thread" - I didn't say I want to start it nor did I say I want to participate in it.I have no questions regarding skating force in tonearms. But a lot of talk and precious few answers, it seems. You said: Regarding the UNI-Protractor and it's "universal" use.
Apparently you haven't worked with it so far and haven't understand it's principle either. Otherwise none of the comments in your last two posts would have been made. I think you´ll find it was I (not you)who briefly explained earlier the way your protractor works. I don´t know if you´ve done this elsewhere, but you don´t do it in your audiogon advertisement. Neither do you credit, or even mention, Dennesen at all in your ad. You say I don´t understand the principle you used. I understand it only too well. cheers . |
Dertonarm Again, since you were the one who brought it up, you said: If you think you can do better - go ahead design it. I already have - as soon as I saw the pics I knew you had missed the basic principle of the Dennesen, and, by extension, the underlying concept, which goes back to Percy Wilson in 1924. Anyone who understands the principle could, with a bit of thought, see how you could have made your protractor more universal, more precise, and easier to use, without compromising the existing features (and you can admit having used it for 25 years, yet haven´t seen this!) You said: So far your comments have shown little more than poor judgement, a fairly high aggression and very little understanding of the subject. Yes, bad judgement in expecting anything other than obfuscation. Aggression? Scarcely. Understanding? I can only promise to try and be more understanding of your explanations. You said: I welcome your attempt to put your name on the wall again and to prepare the road for yourself for a soon-to-be return to the audio market.
No problem with me - as far as I am concerned you are certainly welcome. Thanks, spoken like the true salesman you are. But, unlike yourself, I have no plans to market my add-on to the Uni-Protractor, to compensate for its non-universality. (Nor my new 12" FR66-killer zero antiskate adjustable effective length, dynamically balanced, irregular-pseudo-elliptical headshell arm, (or even my headshell mounted miniaturised preamp which uses the power gained from negating various mysterious breakdown torques to enable a single run of fine cable from the cartridge to the power amp...)) You said: I might react to a post by you from time to time only, but so far very few actually did ask for an answer or a comment. Most were simply lacking content and seriousness. Luckily my last post had two straightforward questions for you to answer, so you might start there. As you must have missed one of them, and misunderstood the other, I´ll repeat: in what way do the Reed, Talea and Schroeder differ from other arms? The Talea and Schroeder appear to have a facility to alter the effective length,(as does any other arm with a slotted or movable headshell) and they have a facility to alter the headshell angle. What is the difference between this and altering the angle in a normal headshell?
The Reed has a normal slotted headshell except for the model with its little azimuth adjusting device.
What´s the difference? I would honestly like to know.
And I am intrigued to know what are these mysterious additional breakdown torques which the above arms don´t have. Cheers again |
Hi Chris,
last topic first .... yes, there is also an UNI-template for tangential tonearms.
1) "We" was referring to the audiophile community - including me.
Kind of universal - in the sense of "we, the people" - i.e. not a club nor a circle of friends, but all audiophiles in the past 4 decades.
2) With mechanical issues I meant that tangential tonearms do ( with various intensity however ) put the suspension of a cartridge's cantilever to considerable stress. Even in a servo controlled tangential tonearm there first has to be a declination from the tangential right angle to move the tonearm.
It is not an apparent immediate issue, rather a long term problem.
I worked with tangential tonearms for 11 years.
There were and are cartridges which are mechanically better suited to withstand the mechanical stress ( especially Supex SDX-1000, original small body ZYX) and a great many which are not.
I didn't really did run into "problems" with neither the ET2, ET 2.5, Air Tangent 2B, Air Tangent Reference nor Goldmund T3F.
I all had them on my turntable(s) and they all did perform quite well and some showed potential for great sound.
I used them with high tech air supply ( Jun Air "Troll") and adjustable pressure and air volume.
The ET 2.5 still today is a best buy.
If mounted with the right cartridge ( low body weight, solid suspension ) and if you do not ask for the last punch, dynamic, air, color and detail in the lower 2 registers of the audio frequency band.
The ET 2.5 improves considerably with increased air pressure up to a certain limit. It does deliver very good bass with a lot of "body" - but not quite the quality I seek.
It is a very good tangential tonearm and if I were looking today for a tonearm in the $1k to $2.5k range, it would still be high on my list.
Cheers,
D. |
Thx for the quick reply D and clarification on the lack of issues other than pump sources with the ET. I have had no cartridge issues in 5 years and it is my main arm.
Is the UNI tangential tool similar to the ET supplied one. I am looking for something that would let me square the line better from the spindle to the bottom of the straight sp10 casing. I am using a homemade extender right that does the job but am curious.
One final question.
You said
"The ET 2.5 improves considerably with increased air pressure up to a certain limit". It does deliver very good bass with a lot of "body" - but not quite the quality I seek."
Are you able to recall what platform/table you mounted the 2.5 on and what PSI you registered at the air bearing, not the pump source.
Thank You Chris |
Dear Chris,
my ET 2 was mounted first on the big Le Tallec tt (modified) and later on the Apolyt (450 lbs chassis, 100 lbs composite platter on radial/axial air bearing, 2 Hz air suspension frequency of whole turntable).
The ET 2.5 was mounted on the Apolyt only.
I worked mainly - as far as I recall - with 0.4 to 0.6 bar.
In american psi this means 6 to 8 psi approximately.
This was read down at the Apolyt's control board.
Cheers,
D. |
Dear D -
That Apolyt is quite the platter and those arm pods. :)
My extensive testing of the 2.5 showed me that 6-8 working psi is a very safe albeit too LOW psi for the 2.5 to show its stuff. So am not surprised at your earlier remarks.
I found the ET 2.5 starts coming into its own around 16 psi to about 20 psi. My findings were later confirmed by Arthur Salvatore who told me his members recommend 19 psi. "Above 19 psi and the arm starts to lose information".
At 19 psi the ET 2.5 has phenomenal PRAT, Bass Attack, HF, sounds the most natural. It competes with arms well above its $2900 US purchase price. I very much recommend to those with the ET 2.0 to have them upgraded to the 2.5 bearing along with a Timeter Aridyne medical pump available on Ebay. These two mods make the basic ET 2.0 arm are a giant killer.
Good luck and much success with your Uni D.
Cheers Chris |
Dear Chris, I found my old files ... last setting with the ET 2.5 was 1.2 bar. Notes further mentioned "threshold - can't take more pressure due to material and problems with re-bouncing air stream".
Cheers,
D. |
Dear Chris, my last post just crossed with your answer - indeed, the bearing of the ET 2.5 can take much higher pressure. I found my tonearm files with the remarks about the ET 2.5 and my last settings were around 1.0 to 1.1 bar - which is, as you mentioned too, about 16/17 psi. Beyond that the re-bouncing airstream and material instability did downgrade the ET 2.5's performance.
Thanks, Chris - the sales on the UNI-Pro exceeded my expectations indeed.
The 2nd production run sold out again.
Cheers,
D. |
Dear Dertonarm,
any signs of the UNI-P2S having left the labratory or even production stage. The world is waiting...
best & fun only - Thuchan |
Dear Thuchan, the full 2nd production run of the UNI-Protractor was just collected by the shipping service. I wanted to have this on it's way first before actually introducing the new UNI-P2S.
The UNI-P2S will finally be introduced and in stock by mid next week. Around the same time when you'll get your special balanced multi-line-to-power amp switch unit ...;-) .....
Stay tuned and enjoy the Munich High-End show tomorrow.
Cheers,
D. |
