Dear all, I would like to add, that in professional audio and engineering - at least here in "old" europe - the discussion about Löfgren, Baerwald etc. is long dead.
Löfgren and Baerwald did their calculations based on mono pick-ups and in a time when modern microgroove records were an idea of the far future.
A mono stylus has VERY different tracking conditions compared to a modern stereo stylus. Stevenson took this into account first and recognized the dangerous conditions towards the inner groove. In later years Rother, Kishimi and others further commented about this.
Among all these later (read: stereo era) engineers diving into the topic of tonearm calculation it was without question, that different tonearm geometries required different calculations.
It is always about effective length, overhang and offset angle. But it is also about grooved area, increasing diameter and resulting increasing difference between inner and outer groove wall, importance of lower geometrical based distortions in area of divergent tracking conditions.
It is all geometry, but for Löfgren and Baerwald (as a direct result of their time and the limited requirements) it was only a 2-dimensional model.
But a stereo groove is a 3-dimensional model and a very tricky one in the last 3rd of a grooved 12" record.
To understand completely what is going on, one must first look and comprehend the whole model - not just a simplified one without the most critical parameters.
This is true in tonearm calculation and as well in tonearm construction.
Cheers,
D. |
Tha's means at the last 1 seg. and not last 2-4 minutes as you states.
Regards and enjoy the music,
Raul. |
Dear Dertonarm: +++++ " Löfgren tried to minimize distortion over as large an area of the record as possible. He did so at the expense of the last and most critical inch of the groove, where the distortion level of his calculation sky rocket. "
this is a misunderstood, that's why exists Löfgren A and B where the highest diustortion at the last inner groove is different been lower on the Löfgren A solution.
So we have choices here at Löfgren's " house ".
Regards and enjoy the music,
Raul. |
Dear Dertonarm: Please makes things easy with out all useless bla-bla that means nothing and proves nothing.
Show/bring here the set up parameters for any of those especial tonearm geometry ( other than FR that you proved was a disater with your parameters. ) designs and then with those numbers we in this open forum and in front of all of us we can make the calculations a see if in reality exist significant ( that we can detect. ) lower distortions not only at inner groove but over the whole LP recorded area.
Facts are the ones that has the " last word ".
Regards and enjoy the music,
raul. |
Dear Raul, you said Dertonarm, everyone is asking here for your precise answers about especially those " special " set up with some specific tonearms. . Sorry, - you are the only one who asks. All others have long understood the context. Cheers, D. |
Dear Raul, maybe you should read Löfgren's own papers in the original language they were written - in german. It help's understanding the matter.
Löfgren A is today more commonly named Baerwald.
Sorry, but Löfgren himself in his later comments ( in german again ...) to his own papers put together the characteristics of his calculation exactly as I described it earlier.
But maybe Löfgren was wrong about his own idea and you know certainly better.
Löfgren A spreads the two zeros further apart - Löfgren B puts them closer together.
Results in lower average but higher maximum distortions in Löfgren B and vice versa with Löfgren A/ Baerwald.
It is still about mono and not about microgroove and not about stereo.
Stevenson knew why he did went in other directions - he did so over 25 years later and with 8 years stereo available to the customer.
Nice to learn you do not hear any distortions - but that leaves a lot of possible explanations.
Cheers,
D. |
Dear Dertonarm: Please makes things easy with out all useless " words-bla " that means nothing and proves nothing.
Show/bring here the set up parameters for any of those especial tonearm geometry ( other than FR that you proved was a dissater with your parameters, even Stevenson was better. ) designs and then with those numbers we in this open forum and in front of all of us we can make the calculations and see if in reality exist significant ( if any ) lower distortions not only at inner groove but over the whole LP recorded area.
Facts are the ones that has the " last word ".
If you decide not to bring those numbers then we could think that you are trying to deceive us either because your ignorance level on the subject or in porpose. In the first case that you are doing in an " inconsciente " way and no harm at all we can't say the same if is on porpose.
Regards and enjoy the music,
raul. |
Dear Genesis168: This could help you too:
www.vinylengine.com/tonearm_alignment_calculator.php
Regards and enjoy the music,
Raul. |
Thou shall useth Lofgren and have no other geometries before thee.
For I am the light, the soul, the oracle, the mathematician, your audio deity.
Book of Raul
Chapter 1
Verse 1 |
Dear Dertonarm: +++++ " Stevenson knew why he did went in other directions - he did so over 25 years later and with 8 years stereo available to the customer. " +++++
this proves that you are totally wrong again. Dertonarm you are " catched " in your own trick/trap that have no single " window or door " to come out.
In the example of that tonearm with 258mm on effective length Löfgren A at the last one inner groove has 0.809% against higher Stevenson figure that is: 0.962%. Even that you states that because Löfgren/Baerwald times were not the stereo ones and they don't take in count but you know that in those times as today: 2+2 is still 4, stereo or not microgroove or not.
Goech asks the same not only me and if you want I can show you here other Agoner's asking the same.
Read my last ( before this ) post, your call.
Regards and enjoy the music,
Raul. |
Isn't it true that the VPI jig that comes with the 10.5i arm is not based on Lofgren, Baerwarld, or Stevenson? I think I read somewhere that Harry used his ears along with some other method...
And how accurate can one align a stylus by eye and hand? |
It is all about geometry, the two null points have zero tracing error and if the set up is off the null points will be different than what we think we have. If bad enough the inner null point could be on the record label for example. A tracing arc with a specific distortion curve should have the same geometric error and distortions regardless of the arm, cartridge stylus or if the record is stereo or mono, I thought?
You can't compare tracing error distortions to amplifier THD specifications, we all know there is more to the sound of an amp than THD figures, but picking a tonarm/cartridge set up geometry that has more tracing error will produce more tracing distortion, unless the mathematics used to figure these distortions are a lie. Or maybe a little extra distortion sounds better to some people.
Anyway, a protractor like the DT, if it makes precise alignment easier is a good thing for those who want to buy it. Getting close to perfect alignment even with the best tools takes time and patience and with practice gets easier and sometimes a little luck makes the set up go faster. Moving that cartidge in such tiny amounts and the eye strain always tests my patience. I still use a MintLP and some arc protractors I printed using the vinyl engine template generator. |
Raul, I really get what you mean and what you are preaching. I have seen those figures and plots many times. You are saying "the facts", "specs" or "numbers" are the last word which I totally disagree.
Ask yourself, what are we after in this hobby? "facts/specs" or sound?
Back to Stevenson. He was 25 yrs after Lofgren. Did you ask yourself why he chose a curve with much inferior "facts" than Lofgren? I am sure he knew the Lofgren "facts" and equation before making his so called inferior curve. Did you think he was stupid or was he fixing some of the Lofgren shortcomings? We all know there is no perfect curve. All have tradeoffs.
Maybe Harry of VPI was also wrong. I guess in your books, he is worse than Stevenson by not using any of the famous curves. Did it ever occur to you that Harry chose a curve that sounds best for his tonearm but not with the best "facts"? |
Jazzene yes, that is part correct. see Harry's quote below. Bottom line, Harry is the tonearm designer and I agree with my 12.6 & 7, his alignment overall sounded better that B or L. This is probably no different approach to the designers of the FR tonearm, Ortofon, SME, rega, Pioneer/Exclusive, SAEC etc etc - they all did not like B, L or S for probably very good engineering and musical reasons - Something Raul aka " Charlie Sheen - Winning " fails to even try to acknowledge or understand. If you go by science, bumble bees can't fly, tell them that when a hive is chasing you. Seriously, I don't use either of those curves, I did it by ear on my system, not by math on a computer. If you go by distortion you would never use tubes, only solid state. I began using the Mitch Cotter system and tweaked it from there.
This is not a condemnation of eithet system, it's just that I know what they sound like (doing this since 1958) and like my system better. That does not say you shouldn't make the guage, it may sound better for you so I would do it.
They said the same thing on Vinyl Asylum and the German guy ran the number and said the distortion is higher, then he listened to the arm and said I understand why he uses it.
Just my take on audio, yours may be different and there is absolutley nothing wrong with getting the lowest distortion possible.
HW |
Dear Genesis168: I understand what you mean with " sound " but we are not talking here about " sound " but what is right and what has higher distortions.
Btw, Stevenson don't fix any of the Löfgren shortcomings. Stevenson always has higher distortions even in the inner grooves, please read my 2-3 last posts or better yet use the VE last link I give to you and make for your self the calculations: it is extremely easy.
I don't give the Dennes white paper link for the figures and plot that you seen " many times " ( good ), I give you mainly for you read all what Dennes write other than those figures/plots/equations. I hope that with a new read for your self this time you understand in deep and clean/precise way: good luck!
Regards and enjoy the music,
raul. |
Dear Trabvrow: +++++ " A tracing arc with a specific distortion curve should have the same geometric error and distortions regardless of the arm, cartridge stylus or if the record is stereo or mono, I thought? " +++++
Bravo!!! because things are so easy and not so " clouded " as he want to paint the picture.
+++++ " but picking a tonarm/cartridge set up geometry that has more tracing error will produce more tracing distortion, unless the mathematics used to figure these distortions are a lie. " +++++
I can't say it with better and simple understanding words. This tonearm/cartridge set up is not a Rocket to Júpiter!
Regards and enjoy the music,
Raul. |
Thanks Downunder. My point exactly. The quote from Harry nailed it on the head. I rest my case. |
Dear Jazzgene: Of course you can make the set up at random by ears only, at the begining of some of us on analog ( very old times. ) many of us that have cero know-how on the subject always made this set up almost by ear! so this is not a new menaing.
But ( always exist those " but ". ) that kind of ears set up has several disadvantages like: ears has no Universal " sensitivity ", the ears/mind are biased for what we like or not and that could be far away from real/true, it is almost imposible to make by ears set up a set up with low distortions, a cartridge/tonearm set up must works in any audio system and how could this be when you make the " voicing " in a very limited number of audio systems and audio items?, etc, etc.
Now, I can tell you that VPI was not made it ( set up geometry parameters ) only using ears at random overhang/offset angle. IMHO what he did was using known geometries and adjust by ears what he likes and that's all, changing some of those mentioned three input data. So in reality was not 100% by ears, the posibilities that you can be " there " by ears at random are infinitely low.
Regards and enjoy the music,
Raul. |
Interesting. I'll take out the VIP jig again and check it out. Currently, my Grado Statement1 is set up with the Mint protractor. By the way, I emailed Yip about my question asking if he might have a better alternative than his 10x loupe and he refuses to get back to me. Kind of not what I expected as when I was in the process of purchase, he was quick to get back to me.
I noticed with the VPI jig that it is easy to fool your own eyes. Because of the white lines and the black jig, you can trick yourself depending on the position you take in front to view. The parallax effect, is it called? It is easier to check it from above but then again, you never can know if the cantilever is exactly perpendicular to the body front... I am starting to think that exact and precise is not in the cards for cartridge adjustment. The stylus might not even be exact to the cantilever, right? |
Dear Jazzgene: VPI designer is a " weird/curious " person:
+++++ " VPI has conducted careful listening tests and determined that every
tonearm we tried sounded better with its mechanical anti-skating
disabled and the tracking force very slightly increased. "
++++
++++ " I did it by ear on my system, not by math on a computer. If you go by distortion you would never use tubes, only solid state " +++++
++++ " OVERHANG ADJUSTMENT:(FIG. 2 AT END OF MANUAL)
Do not go crazy over this adjustment. You do not know if the stylus is aligned
properly on the cantilever. You are also facing a constantly moving
target when playing a record. " +++++
yes, but he take it the work to build a protractor/jig to his customers where he states:
++++ " This adjustment will yield the lowest distortion in the last third of the record, the hardest to track, when playing a typical 12" record " +++++
Certainly not at random and fully by ears.
regards and enjoy the music,
raul. |
OK, Harry listens & then tunes his tonearm.
But Daniel doesn't do listening tests, 'cause he doesn't have all these arms in his hand !
This example of VPI arms, proves the value of an alternative curve other than the standard Lofgren A or B or Stevenson, but Daniel do it on paper! just after knowing the dimentions & angles of any particular tonearm !
IMHO this is extremely interesting & arises questions about real new findings concerning the arm's body (shape-form-contour) construction, as designed & manufactured from it's inventor. Not bad at all, to accept & adopt a formula based on Physics and then apply the mathematics. Maybe this scientific theory could help tonearm designers to build better examples that serve & accommodate this demand from the begining of the production, by having the right shape.
Unfortunately this method remains still a secret and the validation by anyone could happened only by listening tests, after purchasing the UNI-PROTRACTOR with the requested special template.
I apologise if I haven't any clue about this, or even worst, if I don't getting the whole theme right and I've just improvise for the rationalization of these templates. |
Dear Genesis168, sure enough Stevenson was not stupid - nor for certain is Harry Weisfeld. Both knew/know what they are doping and why.
BTW - Stevenson did in his calculation put the 2nd zero tangential error point ("null point") right at the DIN - respective IEC - cutting limit (i.e. innermost grooved area).
So the tracking distortion due to tangential error is always zero at the theoretical innermost groove.
This is per Stevenson's definition.
At this very same point Löfgren A is approx. 600% (6x) more distortion and Löfgren B is approx. 1000% (10x) higher distortion ( based upon that Stevenson is still say 0.1% tangential error distortion and not really zero ).
Löfgren did "sacrifice" the the inner groove for lower distortions between the 2 zero points.
This works especially well with shorter tonearms (9") and with records with long lead out groove.
He did not took into account stereo and did not dream about what wide-cut LPs some record companies would put out in the late 1950ies and 1960ies.
Many japanese audiophiles with 12" tonearms do align to Stevenson and for - again - very good reason.
With increased effective length of a given tonearm (especially so if the tonearm gets really long .. 11" and more) the Stevenson alignment's curve get's better and better vs Löfgren A (Baerwald) and Löfgren B.
In mountaineering you can usually choose between several routes to climb a mountain. Depending on your skills, periphery conditions, preference and experience. Each route has it's benefits and trade-offs.
Some do accept only the first, old and marked route and some do look for new routes.
Same here.
Cheers,
D. |
Travbrow :
"A tracing arc with a specific distortion curve should have the same geometric error and distortions regardless of the arm, cartridge stylus or if the record is stereo or mono, I thought? "
Good question!
With our restricted knowlege till now, this is a fact.
So, what is going on with Daniel's proximity ? |
If those 0 points mark the places whitout any distortion
why are we not able to hear them? One should akspect some
special (Aha!)feeling 'around' them. I myself would ply
only those parts on the records because my aim is perfection.
Regards, |
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, |
That is for sure. I am using the Mint protractor for my VPI 10.5i arm right now. The Mint is made with Baerwald IEC, I believe. |
Dear Daniel,
You are perfectly clear this time at last!
But how you could manage to drive me crazy for so long, it's beyond my understanding.
As I figured at an earlier post, it's all about setting new null (zero) points. Perfectly understood & respected by me. |
Dear Jazzgene, indeed - usually Yip uses Löfgren A/Baerwald for his MINTlp protractors.
Cheers,
D |
Dear Geoch, I am sorry, but I thought this to be clear from the very start. Maybe a kind of "too specialized"-perspective of mine. It is always about the two null points, where to set them and how to manage to keep the "graph" determined by them rather "down" on the distortion scale.
This is what you can actually "see" in a graph.
What can't be "seen" is the effect minute changes in these null points actually have on certain tonearm designs.
Cheers,
D. |
Dear Gentlemans: First than all I want to say again that I'm not questioning any single protractor ( including all the ones named in this thread. ), I'm not questioning VPI undisclose protractor parameters or the DT ones but the " concept " that some tonearms needs " dedicated " geometry set up, first question here: why not all tonearms?
In reality the Löfgren and copy equations/solutions are to determine the exact point/place and " direction/orientation " where the tip on the cartridge stylus must be to fulfil a criterion that could be defined by the cartridge/tonearm owners or the explicit criterion on Löfgren A/B Stevenson or what ever for any given tonearm geometry design ( inclusive you could note VPI site that the designer never talk about: " our specific tonearm geometry " and he don't speaks about because he knew on the subject. Neither Stevenson. )
These are some of those criterion for set up parameters calculations:
+++ Löfgren A and is the solution that gives you the lowest possible amount of tracking error at the inner, centre and outer grooves while keeping this error equal at all 3 points. +++++
+++ Löfgren B and will gives you the lowest overall tracking error of any alignment method but with slightly higher error at the beginning and end of the record than the A method. +++++
++++ Stevenson - a variation on Löfgren geometry optimized for low distortion at the inner groove at the expense of increased distortion elsewhere. +++++
VPI, in reality ( I could be wrong, so crrect me if I am. ) take the criterion to have the lowest distortion in the last 1/3 of the recorded area ( something similar to Stevenson, but not the same. ). For doing this what VPI made was to change one of the three input data on the Löfgren equations ( this is an option but he can determine the desired null points and works for a derivation of the inner groove radius. The result is the same ), the change was in the most inner groove distance ( that in the case of Stevenson he made that that input data coincide with the inside null point and that's why in the last one groove the distortion is cero. ) for change the null points in a way that fulfil that criterion but the foundation of any of these changes are still the Löfgren equations that any one can " manipulate " by algebra to fulfil his criterion.
The undisclose VPI set up parameters IMHO was something with almost no reason for that because in the very first moment that his tonearms and VPI jig/protractor be on customers hands it was very easy to know those set up parameters and this is what happen when VE people take their knowledge and time to analize which were those set up parameters and when they have on hand run calculations against Löfgren A/Baerwald and B . Well you can read it here:
www.vinylengine.com/vpi-tonearm-geometry.shtml.
You can note that in the models 10 and 10.5 even in the last 1/3 of the recorded area ( VPI criterion ) the Löfgren distortion is lower.
Through the thread I posted several times the importance of those three data inputs on the calculations and what happen if we change it:
+++++ I repeat again, in the Löfgren and clones solutions/equations you need three and only three input data for the calculations: tonearm effective length, most outer groove distance and most inner groove distance and is according these three numbers ( that you can choose as you want it. and for any reason you have. ) that you calculate the overhang and offset angle. +++++
+++++ In my last post before the one I sended to you I explain the Stevenson approach as an example on how we can manipulate/change the input data to achieve a different set up parameters. +++++
+++++ We don't need any other geometry parameter to make a tonearm/cartridge set up: effective length, overhang and offset angle are all we need. Even we don't have to care on the null points.
The null points are calculated and used for other things than stylus-cantilever/tonearm geometry set up. +++++
+++++ The Stevenson A cloned/solution ( adopted by several Japanese tonearm manufacturers. IMHO with out in deep analysis. ) is not something with " new " equations, Stevenson only wanted that at the inner groove the tracking error be cero so he taked one of the three input numbers ( in the Löfgren formulas. ): most inner grove distance as one null point and that's all.
This " solution " gives you almost cero tracking error/distortion in the last 30 seconds of a LP with a higher distortions on all the remaining LP surface than in any other " solution ". +++++
+++++ Any one of us can change ( in the Löfgren equations. ) this same input number and Voilá! we have a " new " Perry/Jones/Lopez/etc solution!!!. +++++
+++++ Now, if we change the data input to force better " figures " at inner groove that could be in detriment of higher distortions in the other 90% of the remaining LP grooves +++++
As any one can read on those Graeme F. Dennes white papers any change on that input data makes a change on null points. In those equations the null points are not input data but a calculation output of the equations. Of course, in mathematics you can re-arrange by algebra and could make that the null points be data input.
So, it is IMHO that the criterion is what define those three input data for calculate: overhang, offset angle and null points positions and not the " specific tonearm geometry ".
Other that the most inner groove distance ( inpput data ) we can change ( if the slots's length in the headshell permit it. ) the tonearm effective length data for a higher one to achieve better distortion figures but again not because tonearm geometry it self.
I could be wrong but in this thread and all over the net there is no single real scientific evidence that that is true.
Anyway, I think too that in one or other way the discussion was a learning one and I say this because due to many of the persons posts in the thread I was wrong when I thinked that some of you were " familiar " with all the terms ( terminology ) used on the subject and the most important the meaning of each term.
What's true is that today our knowledge level on the subject is higher than " yesterday ".
regards and enjoy the music,
Raul. |
I did read the vinylengine article on the VPI jig. It was hard to take it to heart because the spindle to pivot for the 10.5i is completely wrong.
He says 262mm but in reality, it is 256mm. |
Somebody has to ask. Given this debate, why are linear tracking tonearms not more popular? Is the cartridge not parallel to the groove across the whole lp?
I use a Graham Phantom.
Just asking. |
Jj2468, this is a very good question. Why not playing the records the way they were cut? Due to the theroetical advantages linear trackers should dominate the market.
They do not.
First of all really good linear trackers are quite expensive, you need a precisely aligned horizontal bases to put the arm on, in most applications you need a vacuum driven guidance of the arm adding a compressor. To reach minimal friction, a precondition for linear trackers, because the cartridge moves via groove edge the total mass of the tonearm the alignment is not an easy one as one may assume.
The length of the cantilever and the compliance issue have some important impact on the interaction of tonearm and cartridge in this concept. This is with other arm concepts a little less critical, also because you have skating. With linear tracking arms you may not use all kinds of cartridges due to the friction issue which may lead to destruction of the rubber parts over time.
Taking into account all these preconditions you may reach excellent results with a linear tracker. I would not like to miss the advantages of this concept. |
Perhaps it is my situation as intellectual Neanderthal, but I, for one, am willing to countenance the idea that a given tonearm design/construction may resonate differently (and therefore sound differently) if forces are applied in different ways (i.e. different offset angles than originally designed), the same way an arm may interact differently with different weight or compliance carts. This is not to say I think it would make a huge difference, but I think that given we are people who talk about getting VTF right to within a tenth of a gram, and levels matched to within a tenth of a decibel, and we change o-rings on the headshell collars, it is not too much to say that applying a LofgrenA geometry to a tonearm designed for a modified Stevenson geometry could sound differently than it would had it been designed with different angles and distances originally. I, for one, wouldn't mind hearing more if people had information, anecdotes, or theories. |
I, for one, wouldn't mind hearing more if people had information, anecdotes, or theories. Hm, this is a brave idea. But it is like a walk through the Darkness without a light. Comparable with saying the word Jehova , "Prophet" or- God beware - "The Earth is round"..... The Audiophile community should be lucky to have such brave minds who do not refuse to go ahead. Like Oscar Wilde once said: "Be yourself; everyone else is already taken" Or like Syntax: There are only 2 ways of sound reproduction. Good and none. |
Dear Jj2468, 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".
Means they minimize tangential tracking error by means of increased effective length while keeping the kind of "practicability" of the pivot tonearm.
Thus minimizing the tangential "advantage" of the linear tracking tonearm.
I have had all the above named tangential tonearms in most all their incarnations in my system in the past 30+ years.
They all were promising and were able - some more, some less - to produce great sonic results (at least for moments or short periods of time).
It were certain sonic shortcomings apparent in all these designs plus practicability issues and long-time problems for many cartridges which ultimately drove me away from tangential designs.
A 11" or 12" pivot tonearm precisely aligned leaves little place to shine for a tangential design, which always and only builds on it's zero tangential tracking error - by sacrifice of other important dynamic and mechanical parameters in a tonearm.
Cheers,
D |
There is much talk about the zero points but I have not
seen any mentioned in particular. Herewith two of them which I got from Howard's article in Sterophile:
'For a modulated -groove-radius range of 56-146.3 mm, they
should be at 61.6 and 118.4 mm; or for 58-146,3mm,at 63.6
and 119.6mm.'
Regards, |
Dear T_bone, you hit the nail on the head. For instance any derivation from a given tonearms design inherent offset angle results in an alternation of it's mechanical model - here it results in an additional breakdown torque, which has profound effects on the skating force. There are some tonearms out there which are designed in almost 100% compliance to Löfgren A/Baerwald IEC standard (all these tonearms being 9" effective length by the way). But then there are many tonearms out there which are not. And for those it is not just about aligning to certain null-points, but also that aligning to them does alter their resulting skating force (among other effects).
Usually one would say: o.k. just make the offset angle smaller and the skating force (resulting of the offset angle) will get less.
Not so as we have a design inherent offset angle and just apply a second one by twisting the cartridge in the mounting area in a different angle.
Thus resulting in a 2nd breakdown torque.
On the other hand there are tonearms like the Talea, which do feature an offset which is "free" to be determined on first glance, but which nevertheless follows Löfgren A IEC with clear given offset angle as specified by it's manufacturer.
This all should shine an additional light on the tonearm alignment topic and why there are different calculations, different focuses and different geometries.
Cheers,
D. |
Dear T_bone, I really try to be funny but it is so difficult to succeed. So herewith my comment on the linear
tonearms. Thy look to me as a very handsome guy but in the
intensive care room. All those tubes...
Regards, |
Dear T_bone: How many cartridges do you know? how many cartridges exist out there?, hundreds and each one resonate and performs in different way due to different cantilever build materials, different cantilever length, different cantilever shape, different stylus shape, different cartridge body build material, different suspension design and different suspension build material, different cartridge compliance, different cartridge weight, different, different and different all.
In the other side we have a tonearm that has its own resonance characteristics and different to other single tonearm out there due to different arm wand build materials, different headshell build materials, different arm wand shape, different tonearm bearings, different tonearm mounting base, different effective length, different, different, different and different all.
Each one of these cartridge and tonearm characteristics ( between other ones. ), one way or the other, has influence in the cartridge quality performance along accurate VT/SRA, VTF, Azymuth, overhang, offset angle, antiskate set up parameters.
Today no one here and no one out there can tell us in a precise way which and how is the influence of each one of those intrinsic cartridge characteristics, intrinsic tonearm characteristics and set up characteristics on the behavior and in the final cartridge quality performance for we can match for SURE one cartridge with one tonearm with the right set up on any recording.
The number of combinations of all those cartridge/tonearm/set up specific characteristics are almost infinity for we can say: " after our scientific research the only best match for this cartridge is this tonearm with this set up ", almost impossible we can do it.
But I don't finish yet, we have to take in count too the LP characteristics and characteristics on was is recorded there: off-center LP hole, waves all over the LP, different recorded velocities at different areas in the LP surface, thickness of the LP, resonance of the LP build material, etc, etc..
These LP characteristics has an influence too in the cartridge quality performance.
And now you think that an offset angle and overhang ( and we can ) different from what we can have through known equations ( Löfgren B, Baerwald, Stevenson. ) calculations choosing on those calculations whatever null points you want ( or what the tonearm designer choosed. ) could makes a difference that we can hear.
Adding thought to that: in theory ( for what you states in your idea. ) for each single cartridge/tonearm combination and for each one single LP we need different offset angle/overhang set up for be exactly " there ". Makes sense this for you?
I respect your opinion but I would like that you explain how is that? how can you/DT aisle/isolate that specific offset angle/overhang from all other each one cartridge/tonearm/set up/LP and from the combination of all those characteristics to know for sure that influence ( for the best or for the worst ) of the un-orthodox offset angle/overhang and that what we are hearing is because of them and not because the cartridge cantilever on playback is out of that offset angle set up that we made it in static playback condition or those tiny changes on VTA/SRA we have during playback due to LP imperfections where even there are tiny changes with the VTF too?
Where is that mathematic model that take in count all those different factors/characteristics that can tell us on playback ( motion not static way. ) which will be the quality performance level ( with lower distortions over the LP recorded area. ) in a cartridge and each one factor/characteristics " weight " in that quality performance level and of what kind is that influence?
I have no doubt and there is no doubt at all that you, Dertonarm, me or any one out there can't shows that great simulation model and IMHO till this happen ( I really hope some day its happen. I loved when this happen ) everything any one of us think or talk in the overall subject are mere speculations with no precise and proved foundation.
To make things " worst " we have to think that many of us likes some kind and different distortions and different distortions level even to some of us like higher distortions that other people or we are unaware to detect different distortion intensity levels due that our ears are not good enough, due that we are not trained to do it, due that we don't care about or due that our system has not that resolution level need it to.
We can go on on this thread making speculations of every kind but IMHO I think is useless.
Gentlemans, today we have what we have and nothing more. I hope we can improve in the future but certainly not an easy task on this whole cartridge/tonearm/LP subject. Today IMHO we have more questions than answers.
Regards and enjoy the music,
Raul. |
We know how its sounds but we don't know exactly and for sure why/how sounds that way, we all have only speculations about but nothing more than mere in good faith: not proved speculations.
As some of you I would like to have/know the true proved scientific overall theory behind the why's on quality performance level between one cartridge and one tonearm running a recorded specific LP and not only to improve my knowledge level on the whole subject but because when we know that ( in the future ) then we have the answers to all and each one questions and finally the right cartridge/tonearm set up.
Till that day IMHO we have to make our best effort with the proved tools we have on hand hopping/thinking that the best is waiting for us in the future.
Regards and enjoy the music,
Raul. |
When I said: proved, means ( between other things. ) that always works and works with the lower distortions measures.
raul. |
Dear T_bone: Do you think that all or some of the tonearm designs out there taked in count all those characteristics ( cartridge, tonearm, set up and LP. ) I posted along that that tonearm design worked always best with the in theory tonearm design geometry choosed for those set up parameters ( overhang/offset angle. )?
I know that some tonearm designers are reading this thread and IMHO it will be " healthy " their each one opinion why they choosed what they choosed on the sole/aisle specific tonearm geometry design/parameters that is only one of several and IMHO not the main characteristic that affects the cartridge quality performance level.
Regards and enjoy the music,
Raul. |
T_bone: We in our tonearm design don't take it either, we concentrate/focus on the main overall tonearm characteristics that makes " the difference " a true differences for the best and for the best quality performance with any known cartridge.
Regards and enjoy the music,
Raul. |
Dear Don Quichote, what do you think about linear trackers? |
Dear Thuchan: The best for cero traking error with many trade-offs as the ones you pointed out.
It is a good choice?, yes it is if fulfil your mind sound reproduction expectatives to handle a cartridge for this cartridge can shows you the best it has.
Regards and enjoy the music,
Raul. |
