Dear @geoffkait : Yes, it's geometry and affects the alignment set up.
The VTA/SRA is changing continuously at each and over the LP side due to those macro and micro waves in the LP but we can't do nothing about. So, we stay with the choosed alignment. It's a non-evitable trade-off.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @geoffkait : """
That's why the geometry should (ideally) be changed for almost every record. """
Can you share with us a wider explanation about?, is interesting to know why we need to change the geometry at each record.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @billstevenson : """
We do the best we can. And you know what? Don't despair, our efforts are not in vain.... """"
in those words you resume what I try to explain through my last post to you.
Now, the cartridge/tonearm geometry alignment it does not cares on all or any of the imperfect characteristics analog/LP has. Always we have to try that that set up been do it with high accuracy.
"""
a vinyl record very often sounds better than the digital equivalent for all it's claimed perfection. ... """
Today that statement is so controversial for say the least. Today digital technology advanced " ligth years " in the last 10 years and I think that today is way superior ( everything the same ) to analog/LP experience.
Digital is still growing up almost single day. I enjoy both formats but I know that digital outperforms analog. We can " close " the sun with one " finger ".
Analog is at's limits when digital still growing up and this characteristic is a welcomed for any music lover and audiophile.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Sorry, in last sentences we have to read: accumulates instead acculates.
R. |
Dear @billstevenson : """
How critical is the geometry issue in practical terms? Records are imperfect anyway. Get everything dialed in for side A only to discover that things are skewed for side B. """
Well, what means practical terms?. For you can be something different than for other gentlemans.
My take is that with analog/LP everything is of critical importance and certainly the cartridge/tonearm set up is extremely important and must be accurated. It makes a difference for the good or bad depending on that accuracy levels in the set up.
I totally disagree with the statement you shared because if we think in that way then what @stringreen posted about the Fozgometer " alignment " has no importance for almost no one when in reality it has.
Why we need to take care as better we can of any single parameter/set up in analog/LP?, because is a medium totally imperfect and we can't acculates additional " imperfections " in that " equation ".
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @slaw : """
But the 2nd pivot mod also changes the original design concept, thereby making it (not a unipivot anymore). This is, I think, the argument Raul is making and the point I was initially referring to. """
That's it, thank's to put the " ligth " on what I wanted to explain with out to much success.
@billstevenson , only for you can think about: the VPI unipivot and the one with the 2nd pivot overall are the " same " but the dual pivot performs way better.
My starting participation in this thread through my Stringreen anser was that the dual one performs better because the 2nd pivot gives it a way better stability.
Now, that was and is my argument but you disagree telling that the unipivot has no un- stability problems ( when in reality has. ). You posted " facts/tests " trying to prove it with no success.
So, why all the named tonearm manufacturers gone for the dual design ( changing from unipivot to dual pivot. ) and all dual pivot tonearm owners attest with out doubt the dual pivot better performance if it's not that the dual pivot has now better stability that's something the cartridge ask/shouts for it.
No pun intented, just think about.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Btw, Durand tonearms goes for the dual " fashion " too. Bill, can you wonder why?
R. |
Dear @stringreen : """
I can't help wonder why there is so much discussion on this. Raul thinks the single pivot is flawed because it is unstable (wiggle)...the 2nd pivot stabilizes the arm and thus corrects the issue. It me it sounds better with the 2nd pivot than without. """ you are rigth and agree. I don't know why @cleeds and @billstevenson makes reference that I'm " against " your 2nd. pivot experiences when I'm not. Even at the very first posts in your thread I posted: """
So, if your VPI is no more an unipivot then what you have is a serious improvement in your listening experiences. Good. ""
stringreen OPThanks raul.....the 2nd pivot is certainly an improvement """
After that I posted to @billstevenson that his own experiences with the 2nd pivot in the VPI confirm my take in the true unipivots ( not dual pivot designs. ). Here the Bill posts:
""" my Prime single pivot tonearm was recently modified and significantly improved sonically by the addition of a second pivot """ """ It is doubtful that anyone who does this will decide after experimentation that the 2nd pivot does not provide a positive benefit. """ The OP statements in his thread confirm my point. """ Then I posted: """
2nd pivot according my statements provides better stability. The only change in the VPI 2nd pivot is just the 2nd pivot that is what makes the difference. """ So what's all about? other than the direct @cleeds insults to me. @halcro , as you know the Continuum tonearms are dual pivots so both don't take advantage of that theory you speaks: "" is the virtual elimination of 'friction' at the pivot point......""" It's only a theory and does not happens that way. A subject for other thread. @billstevenson , VPI is one of the last tonearm designers that changes from unipivot to dual pivot and now to gimball ones and before VPI other did it as Graham with the Phantom2, Basis, Moerch, Continuum, etc. I wonder why if the true unipivot is so " grandious " design they changes or prefered the dual pivots or gimball ones?, these facts means something very serious about. Not enough proof for you? then is up to you that are a scientist that can't prove directly what you posted. No, I'm not and I never said I'm a scientist. So what?. Regards and enjoy the MUSIC NOT DISTORTIONS, R.
|
Dear @cleeds : Good that agree with bill but in that regards are wrong because the Bill's facts/tests were not created to measures the stability in tonearms subject. So in this regards means nothing.
I'm not talking if you love unipivot kind of sound or if you do not, this is not the MAIN SUBJECT but its inherent unstability.
You said: """ that make them inherently flawed is just nonsense. """
but you did not say why is inherently flawed. Through my posts in this thread I explain those facts in a wide manner, read it again and please please come back here and tell us the why's of that " inherent flawed ".
You followed: """ There are reasons that unipivots endure in the marketplace... """
As several other audio " myths " is only because unknowledge level about. Almost all audiophiles are focus on what we like and not in what SHOULD BE that is where lives the MUSIC and audio hobby.
That " should be " is something that each one of us have to make and take a day by day learning path where in many audio/MUSIC subjects on that whole " should be " are almost unknow for many of us.
Not an easy process task that it's not only time consuming but dificult to understand and where we need to ask our selfs: what is happening down there, at each single step that any audio link makes its job.
In the case of the ridding cartridge job almost we have to analize as if we were the cartridge and have the vision of " our " job ridding those tortuos LP grooves and all what this means. We have to do first with out taking in count TT or tonearm but as a stand alone cartridge and from here analize what in the " hell " are the cartridge needs to fulfill its very hard task.
It's an overall process at each step, we have to go as deepest as we can with patience.
We have to analize at least from where comes the recorded information in the LPs. Well, that normally comes from what the recording microphones pick-up in NEAR FIELD not at 30m.-50m. from the music source as happens when we are seated in a music hall.
Those are incomplete examples to sooner or latter know how everything in audio SHOULD BE and improve our listening quality levels.
The rewards are fenomenal and we learn several things as if we discover a new audio world.
When we start to make the audio systems changes to achieve that " should be " we will know that in the past we were " wrong " and in this " new world " we really enjoy the MUSIC as never before.
I'm still in the quest to finish that " should be " and I can tell you that's worth to do it.
I'm not different of each one of you: I'm a MUSIC lover and I want to achieve the true best listening experiences through my home stereo audio system. Tha's all and as many other audio items unipivots can't help to approach that targets.
Anyway is up to each one of us.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @cleeds : I'm still waiting for your answer/information about that my post was " inherently flawed ".
I ask you again bacause it's very easy to " say this or that " as you posted but any one of us have to have the gentless to say why some one is wrong or like in this case " flawed ".
Please share the information on why you are thinking that.
From my part I never post any kind of critic/information just as yours, always give a wide explanation why I think that. All the gentlemans that posted in any internet forum have the responsability to give complete information according to our experiences and knowledge level. Critics with out that " foundation " does not helps any one and all are in the forums looking for HELP.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @billstevenson : I agree with almost you said in your last post.
" Each of us has preferences.... """
My take is to forget our " prefrences " or what we " like " and stay " centered " on what " should be " and start to build the " new " system from here.
When we arrives to that " should be " then what we listen in our " new " system always we like it and always be a huge improvement over what we had when our system choices were made/headed it for that " what I like it ".
Search for the Holly Grail?, ask you: WHY NOT ! ! ! ?
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
Btw, @folkfreak , I listen the Durand but not on my system. I think that each day is a learning day and this is my " natural " attitude.
@cleeds, the times of frustration I left it to many years ago to remember it. You are wrong in that too. |
Dear @folkfreak : Sorry for the misspelled but unfortunatelly my English is to bad, sorry.
Now, you posted:
"""
I imagine myself as the cartridge tracking the record and I thereby know unipivots cannot work ...""""
you summarize in wrong way maybe because the misspelled post explanation.
A better summarization could be to be certainly of what are the specific cartridge needs and what those specific cartridge needs really means and how a tonearm can fulfill it if exist one that can do it that certainly does not exist yet.
How can you know if an unipivot can works fine with any cartridge if you don't know or can't understand which ones are its needs other than a tonearm holds it.
When you learn those cartridge needs you will know for sure that two things that the cartridge does not needs are: unipivots and undamped tonearms and this is a fact that I don't need to prove it.
What you and @cleeds needs is to do your job and find out for your self process which are and why those cartridges needs.
Everything in the day by day world is changing where audiophiles are immutable, nothing change and we make nothing to change but stay sticky to old information thank's to that corrupted AHEE where any one of us belongs.
Due to your immutability " stage " and with out be conceit or arrogant in anyway: I'm " ligth years " a head you enjoying MUSIC as you can't even imagine and not because I'm better than you only because I'm changing/learning/moving as the wrold does. Folkfreak good for you: stay immutable and sticky on what you like instead to change learning on what SHOULD BE.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @cleeds : Good that agree with bill. I that regards are wrong because the Bill's facts/tests were not created to measures the stability in tonearms subject. So in this regards means nothing.
I'm not talking if you love unipivot kind of sound or if you do not, this is not the MAIN SUBJECT but its inherent unstability.
You said: """
that make them inherently flawed is just nonsense. """
but you did not say why is inherently flawed all what I posted .. Through my posts in this thread I explain those facts in a wide manner, read it again and please please come back here and tell us the why's of that " inherent flawed ".
You followed: """
There are reasons that unipivots endure in the marketplace... """
As several other audio " myths " is only because ignorance. Almost all audiophiles are focus on what we like and not in what SHOULD BE that is where lives the MUSIC and the audio hobby.
That " should be " is something that each one of us have to make and take a day by day learning path where in many audio/MUSIC subjects on that whole " should be " are almost unknow for many of us.
Not an easy process task that it's not only time consuming but dificult to understand and where we need to ask our selfs: what is happening down there, at each single step that any audio link makes its job.
In the case of the ridding cartridge job almost we have to analize as if we were the cartridge and have the vision of " our " job ridding those tortuos LP grooves and all what this means. We have to do first with out taking in count TT or tonearm but as a stand alone cartridge and from here analize what in the " hell " are the cartridge needs to fulfill its very hard task.
It's an overall process at each step, we have to go as deepest as we can with patience.
We have to analize at least from where comes the recorded information in the LPs. Well, that normally comes from what the recording microphones pick-up in NEAR FIELD not at 30 m. from the music source as happens when we are seated in a music hall.
Those are incomplete examples to sooner or latter know how everything in audio SHOULD BE and improve our listening quality levels.
The rewards are fenomenal and we learn several things as if we discover a new audio world.
When we start to make the audio systems changes to achieve that " should be " we will know that in the past we were wrong and in this " new world " we really enjoy the MUSIC as never before.
I'm still in the quest to finish that " should be " and I can tell you that's worth to do it.
I'm not different of each one of you: I'm a MUSIC lover and I want to achieve the true best listening experiences through my home stereo audio system. Tha's all and as many other audio items unipivots can't help to approach that targets.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @billstevenson : No malign action here. I own, owned and heard several unipivots including VPI and as you I know what I’m talking about.
Your " facts " about can’t prove that I’m wrong in my main " at micro levels unstability in any unipivot tonearm ". Reason is that those measures were not made it to prove it but to prove other targets.
We have to know what kind of measures where and how to achieve it to prove a specific subject. This time: at micro levels unstability in unipivot tonearm designs.
Your " facts " were as something of every day audio discussion, like this:
""" measures shows that these two amplifiers mearsures exactly the same but sounds different ! ! ? ? ! """
Problem there, that we don’t know what to measures to explain why sounds different. Same with your old " facts ".
In the other side you posted two facts that proves what I’m talking about:
""" my Prime single pivot tonearm was recently modified and significantly improved sonically by the addition of a second pivot """
""" It is doubtful that anyone who does this will decide after experimentation that the 2nd pivot does not provide a positive benefit. """
2nd pivot according my statements provides better stability. The only change in the VPI 2nd pivot is just the 2nd pivot that is what makes the difference.
The OP statements in his thread confirm my point.
Bill, remember that those huge forces at cartridge stylus tip during playback " makes " its works, the movements in the stylus tip has no precise pattern due that happens at random.
Here it’s not who has the reason, it’s only " common sense ". I respect what you posted but unfortunatelly does not proves what you think are proving. At least not if I’m wrong for this you need different " facts ".
Btw, you can make your research and try to learn ( for sure. ) what measures we have to do that can explain my point or better yet: that can explain why I'm wrong !. You was whom ask for facts due that those two stamentes posted by you were not enough for you be satisfied ! ? ! ?
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @billstevenson : @folkfreak is rigth. The tonearm in that video is a VPI unipivot one.
@slaw posted """
it's easy to find videos of the arm swaying side to side until it becomes steady by way of natural causes ..."""
as a fact that instability happens in any unipivot tonearm, is inherent in this kind of tonearm bearing design.
In that video we can see the instability at macroscopic level but that instability coninue all over recorded area at microscopic levels.
As folfreak said all those already were under discussion through this thread.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @billstevenson : I know that you did not read all my posts here and you don't have to do it but in one of them I posted this link and you can see what happens with any unipivot tonearms ( in this case VPI. ) about that unstability true problem that does not happens with pivot fixed bearing designs. Data?, here is a fact:
https://www.youtube.com/watch?v=iTTLM9gPU9o
Regards and enjoy the MUSIC NOT DISTORTIONS, R. |
Dear @robes: A clamp normally reduces the resonances/vibrations/feedback existent between the TT platter-mat/LP surface with the stylus tip. and from this point of view always is a benefit to clamp the LP.
With clamp or with out it the unipivot tonearm stability will be there, you can't avoid it using any clamp type. The second pivot is not the total cure, it's only something to reduce the stability problems. Best is to look for pivot tonearm with fixed bearing design because the cartridge needs full proof stability: zero tolerance.
Unipivots are more easy to design but is not a tool to use for a cartridge ridding LP grooves. Is a mistake to use it that goes against the quality level performance. I know that some audiophiles really likes it but ( even that they don't know. ) it does not means is rigth.
We have remember to " see " the stability subject at the microscopic level that is where the cartridge stylus tip has to " negociates " those " rude " LP grooves. Believe me that the cartridge tracking job is a really hard and huge task and not so simple as we can imagine it.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @moonglum : Btw, I'm talking on the Technics EPA 100 MK2 not ther tonearm that comes with the 1200.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @moonglum : Achilees heel in fixed/gimball tonearm bearing designs?
Well, as in any tonearm design all depends on the design it self and the quality excecution level of that design.
In the fixed tonearm bearing design there is no inherent achilees heel as in all true unipivots. Gimball type tonearm bearing designs can comes with " mistakes "/bad design in that regards but what is happening down there and that you explain in wide way ( brinelling. ) is not inherent to those kind of design.
You can take for an example a vintage tonearm design as Technics where the designers decided to use four bearing points and use at each bearing points 5 ruby balls ( 20 in total. ) with a roundness tolerance of 0.5u that permits a bearing friction number ( in all directions. ) of less than 5mg. and it´s not only that but all the care Technics took for its production. A superlative product that even today is the " envy " for any tonearm manufacturer.
Brinelling there is almost non-existent. Of course that there are truly bad designs as the FR tonearms that in that regards is one of the worst examples you can find out but even this those stylus tip/groove huge forces makes that the tonearm moves!.
In the other side, the very tigth tolerances on today gimballed designs makes that you don’t have to worry about. In the past almost no one use ABEC 9 balls and today is a must and almost every one use it at the tonearm bearings.
Everything the same unipivots are in total disadvantage against giball/fixed bearing tonearms.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @stringreen : Yes, for years I had the same kind of experiences through several tonearm/cartridge combinations.
The important issue here it's that the skate force exist through all the cartridge ridding in a pivoted tonearm.
That skating vector is part of all the different kind of " forces " that has influence in the stylus tip groove ridding " job and we just can't say: I like it more with out the antiskate mechanism.
Again, I'm talking on what we need to do or better: what the cartridge stylus tip needs and not what we like it because as " usual " we are accustomed to higer distortion levels that what we can think or imagine it.
Perhaps a " trouble " with AS mechanisms is that the developed skating force is a variable one all over the LP side and at each groove is changing and for that skating force can't has real influence we need a very preise antiiskating mechanism that can mimic exactly the inverse skate range at each groove and till today I don't know any single tonearm that fulfill that needs.
But all those does not means the cartridge ridding does not need it because we are talking that we have to have extremely care for the stylus tip pick-up precise groove information and the AS if not compensated goes against that target.
I know, that the AS task is almost imposible to do it in the rigth way.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @folkfreak : So, those tonearms are not any more true unipivots ( good. ) but neither a fixed/gimball design.
Anyway, anything out of an unipivot design is just better by a wide margin.
What can be really interesting on the whole subject is to take the best quasi-unipivot design and the best fixed one and through an electronic microscope in slow motion see what is happening at the stylus tip/groove on playback becaause at micrtoscopic levels you, me or any one can't see if exist that wobble in those unipivot designs.
At those microscopic levels we can see that the stylus tip is literally " jumping " in the grooves when ridding and between other things that's why is so important to achieve always a " safe " resonance frequency number between the cartridge/tonearm.
I think that any tonearm must be designed to fulfill the cartridge needs. Understanding those complex cartridge needs.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
"
Remember that I'm talking on what we like when listening to unipivots. "
that has an error ( my mistake. ) and must be read in this way:
Remember that I'M NOT talking on what we like when listening unipivots.
R.
|
Dear @stringreen : "
I'm sure in the future, there will be even more modifications and applied engineering to bring tonearm designs to increased abilities "
I can't say it in better way. Agree with.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @moonglum /friends: Torsianally stable?, any tonearm suffers from that torional huge forces but the unipivots are where affects in the worst way to that very hard cartridge job.
In any cartridge mounted in any unipivot tonearm design combination first than all puts the " possibilities " to be nearest to the recording really far away.
That item combination is more an acrobatic act that a listening experience. Unfortunatelly, that acrobatic act is made it with no real success.
We only have to think the total unstability that persé has any cartridge that rides through that very tyny stylus tip dimension and at the other extreme ( unipivots. ) side an inverted " stylus tip " that function as the pivot.
It's imposible to have any kind of stability in between, a stability that's a must to have for the cartridges can makes its job.
Even in static way an with the stylus tip in the LP with the TT spining exist no real stability. Imagine when in true motion ridding those grooves with all those huge ( every direction ) generated forces ! ! !
Remember that I'm talking on what we like when listening to unipivots.
Btw, damping can't disappear the unstabilities at microscopic stylus tip as pointed out Don.
Even, in the VPI case, its design comes not caring very seriously about the needs for anti-skate.
I think that unipivots were and are designed because are easy to design, manufacturer and assembly. Additional comes with low market price. Well not so in the price subject when exist unipivots over 20K and there are audiophiles willing to own it ! ! ! Incredible.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @folkfreak : It's obvious that the tonearm in that you tube video is an unipivot design or a gimball one with a severe extreme bearing damages.
The video is a " dramatization " that helps to understand what is happening in continuious way at microscopic stylus tip during play of any cartridge in any unipivot tonearm design and in little lower way in quai-unipivot ones.
Forces are so huge that gravity alone can't correct it.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear friends: That " terrible earthwake " is unaceptable by any audio standards and that's is what happens with all unipivots or quai-unipivots.
A very well regarded tonearm unipivot with a tag over 25K states in its site:
"""
it is subjected to the mechanical vibrations from the musical source (the stylus moving in the groove), and it should before all not damage them and let them interfere with the electric signal coming from the cartridge. Each of the tonearm's constituents carries a crucial responsibility in the transmission of these vibrations, so every element, down to the smallest screw plays an essential role in the resulting sound. Those who claim that mechanical devices don’t have a sound don’t understand the nature of sound. Everything has a sound. Every piece of matter enters in vibration when it’s moving and that is what gives it its distinctive sound. """
seems to me that the tonearm designer of that company has very clear ( ? ) that critical subject and ( for me ) is just out of my mind why he choosed an unipivot design to fulfill that statement when it can't do it.
Btw, there is no single advantage in an unipivot design. What we listen through it are only higher distortions and that's all.
Cartridge needs " perfect " stability in a tonearm with NO earthwakes.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @moonglum : Great facts/information. As I said exist formidable audio information all over the net and comes from experts.
Facts that can makes a paramount differences in each one of us ignorance levels, obviously all of us can improve our knowledge levels, skills and tools !!
Btw, @dodgealum , you own the Levinson/VPI tonearm and in the " you tube " link I posted here we can see a way " terrible earthwake " down there that if it's happening then exist something really wrong in that tonearm design.
Would you comment about?, appreciated.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
@moonglum : "
Van Den Hul states : "But the most important thing is record wear. I measured temperatures using a thermistor with a thin wire around the tip. A conical tip went up to about 140 deg C, but my one was 60 deg. I would like to come down further, but this was the lowest possible value."
R.
|
Dear @moonglum : Handbook for enginners: "
"It has been experimentally shown that with such high pressures and forces of friction between stylus and the vinyl, that the outer skin layer of the record material melts as the tip slides over the plastic and then refreezes almost as fast as it melted. It has been suggested that since the melting temperature of vinyl is about 480 °F (248 °C) that the same temperature exists in the contact area.”
You can confirm here the fact you was thinking about and at the same time other additional fact that confirms about those very huge forces generated down there.
Btw, I can tell you that my very high ignorance levels brought me to a extreme high frustration levels. Never mind, such is life.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @dodgealum : This video is from the Levinson tonearm and I hope that what we see between the the second 10 and the 16 second is not what happens with that fixed bearing tonearm manufactured by VPI: https://www.youtube.com/watch?v=iTTLM9gPU9oAnyway, the video is a very good fact that confirm what that those huge forces makes with the cartridge/tonearm and why unipivots are out of question. Regards and enjoy the MUSIC NOT DISTORTIONS, R. |
Dear @moonglum : FS. is a great designer and I forgot his tonearm designs.
I experienced the Kuzma 4-point and is very good design and can understand why MF use it. In the other side: can any one justify against quality level performance a 28K on tag for a " simple " tonearm?
Well, maybe I don't know. Coming from a professional reviewer puts me ore doubts than certainty about.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @moonglum : If I remember the latest information about was by Dr. A:J Van denHul who measured 160° celcius between the stylus tip and groove.
In the other side the best confirmation on the critical importance for tonearm true stability bearings to " avoid " all those huge developed forces are the listen experiences by @stringreen and @dodgealum whom owns the true unipivots and compared against the quasi-unipivot ( stringreen. ) and the gimballed one VPI model. Both very precise in the improvement levels.
That's the same experiences audiophiles had when changed from the original Graham tonearm ( similar design to the unipivot AC 3000. ) design to the Phantom ( I think you own this model. ) or from the DP-4 ( similar unipivot design to Highphonic. ) to de DP-6/8 or even the Cobra.
Good that after so long time some tonearm designers took in count the terrible unipivot disadvantage due to that unstability because this is what the cartridge does not needs and is not asking for. We always have to understand the cartridge needs at microscopic levels because almost all comes from there.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
|
Dear @moonglum : There are several audio subjects we are not totally aware of or that just we need to remember it.
Cartridge/tonearm/LP relationship is the most important subject in the analog experience.
Those very high forces generated in between puts its own " signature " on what we are listening.
It is not only that ( for me ) unipivots are forbidden tonearm designs but at almost the same critical importance is the tonearm necessity of been perfectly damped through its design or other way: forbidenn.
We have to remember that all those generated vibrations/resonances/errors between the LP/cartridge/tonearms continuously are generating feedback through that " circuit " adding complexity to the whole main subject.
Good that you had that " number " at the tonearm bearing.
Over the net exist " formidable " scientific information. AES/BAS are some sources about but I can see that in your country you already was aware of all those.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
Dear @moonglum : Thank’s, you are rigth and yes: who’s counting but me. Good. Ignorance is the " war’s mother " and that’s why I always try to improve my ignorant levels. @moonglum in confirmation to your posts and mine here high-ligths from specific experts studies on the subject and its importance: """ The stylus tip, when in good condition, touches the groove walls at only two points. The entire weight of the stylus and the structure which holds it is concentrated at these two microscopically small points. When this concentration of pressure upon the points of contact is calculated, we find it to be approximately 26 tons per square inch. The walls of the record grooves are, of course, subject to the same pressure, but only for the fraction of a second required for a particular section to move past the tip as the record rotates. The stylus tip must travel well over one-half mile of surface each time a 12" LP record is played...with 26 tons of pressure per square inch. """
""" The most interesting photos to me described the "infinite" amount of force applied to the groove by the spherical and elliptical stylus designs. These designs effectively rest on 2 round contact points about 80%-90% of the way down into the groove. Since the contact points are rounded, the contact area is infinitely small, so no matter what the tracking force, the tracking pressure at the point of contact is effectively infinite. """
""" Getting back to the ripples caused by spherical and elliptical styli near the bottom of grooves, there seem to be 2 forces at work. The stylus tip gets warm on the two contact surfaces after only a few seconds playing. At that point you have a hot stylus pressing infinitely hard against vinyl and this can easily create substantial softening (melting is not required, in fact melting is not the mechanism that creates the ripples). After the stylus has passed any groove location the after-effect of the stylus bouncing merrily along in the groove causes the rippling. ..... But there are so many stretching, bouncing, musical, pushing/pulling pressure waves being generated, some driven into the disc and some being generated as the stylus tries to drag the vinyl along with it, that as the soft vinyl hardens again, it reacts in a resonant fashion. ""!"
""" From page 975 : "because of the small area of contact that exists between the stylus tip and the groove, the pressure against the groove wall can rise up to many thousands of pounds per square inch. For instance, if the wall receives 0.7 g of force applied through the contact area equal to 2 ten millionths of an inch, the pressure is 7726 lb/squ.inch. It has been experimentally shown that with such high pressures and forces of friction between stylus and the vinyl, that the outer skin layer of the record material melts as the tip slides over the plastic and then refreezes almost as fast as it melted. It has been suggested that since the melting temperature of vinyl is about 480 °F that the same temperature exists in the contact area. If the record material is metal, which happens when metal mothers are played, then the pressure increases to 20,000 to 30,000 lb/squ.inch, and the temperature can reach 2000°F because there is no plastic deformation of the groove wall. This explains why styli made of diamond, which is nothing more than carbon, literally burn up or wear out in a couple of hours when they are used to play metal mothers. """
In my past post I don’t speak of other parameters that can increment/modulate those very high forces that per sé increment the unstability problem in the unipivots during playback.
The recorded grooves were recorded at different recording velocities according the music information needs this has a direct effect on those forces that push the tonearm bearing, stylus tip shape has its own effect as the stylus tip wear through the time that between other things increment the friction between stylus tip and recorded grooves in encrement on those forces, skating has an effect too as the VTF and SRA that it’s changing almost at each groove due to LP imperfections. Of course that self cartridge tracking abilities contributes too.
All those very high forces affects any kind of tonearm bearing designs but on unipivots is the worst case.
@stringreen , I posted:
""" As always I’m not talking here if we like what we are hearing through unipivots or dislike, this is not the issue but to stay nearer to the recording that means we need to stay with distortions ( of every kind. ) at minimum and unipivots can’t help to achieve that main target. """
That’s what I’m talking about. As unipivots does not exist any single tonearm design with out trade-offs and each one of us choose which trade-offs are better choosed to be nearest to each one targets. Unipivots are out of question to achieve my today targets.
It’s nothing wrong with you because your system today fulfill your targets. Fine, that's what each one are looking for. Btw, thank’s for your invitattion and you are welcome to come at my place in México city anytime.
Regards and enjoy the MUSIC NOT DISTORTIONS, R.
Btw, as always the post of that person came only to " hit me " ( obviously with no success. ) with no single fact because has no facts. Pity. |
|
Dear @stringreen: True unipivots are a " mess/nigthmare " for pick-up recorded information from the LP grooves due to its real unstability at micro groove levels. Yes, I don't like it. The cartridge stylus needs must be fulfilled by the tonearm and " stability " for is perhaps the first and main target for any cartridge when it rides.
At our sigth we can't see that unstability, we think is steady at the grooves but it's not.
So, if your VPI is no more an unipivot then what you have is a serious improvement in your listening experiences. Good.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R. |
