Hi all
Triggered by haiteflon latest post, especially from the last sentence, here is the letter which I considered too long and too complicated back in my last post:
"Well, I will try to expand on my writing found in post#26 (page3).
I will start with a theoretical treatment of the subject (i.e. using some assumptions which later on will be dressed off their axiomatic clothes and exposed naked). Some drawings (attachment) may help.
All these forces invoke the 3dimentional movement of an assumed rigid and mass-less cantilever beam which is pivoted to an assumed infinite mass via an assumed loss-less 3dimentional ideal joint.
The result of this arrangement is that the other end of the beam where a mass-less magnet is attached to, follows precisely the movement of the needle according to the formulas that apply to a first class lever http://en.wikipedia.org/wiki/Lever#First-class_levers and assuming that no external forces act upon the magnet.
Now from the 3dimentional movement of the magnet, we would very much like to subtract the X axis (Fore-Aft) movement. So, we ask from the pivot joint to 100% transmit this movement to it’s (infinite mass) support.
At the pivot point(s) the Newton third law inevitably holds http://en.wikipedia.org/wiki/Newton's_laws_of_motion#Newton.27s_third_law:_law_of_reciprocal_actions , and it is applicable to all the forces acting on the beam.
It becomes clear why we would like the pivot support mass to be as large as possible and be as rigid as possible: If the mass and stiffness of the pivot support is infinite , the pivot point remains fixed in space.
The less of these qualities it possesses, the more the pivot moves in space.
If the pivot moves in space, this movement will modulate the movement of the needle which is transmitted (through the rigid cantilever) to the magnet. We don’t want this.
Let’s do the first step closer to reality now and deal with the:
1. Loss-less 3dimentional ideal joint: It has to induce as little friction as possible and have as little play as possible at the same time.
2. Infinite mass pivot support: Make it an infinite mass cartridge body.
Let’s do the second step:
1. Close to Ideal, but a real joint: A gimbal http://upload.wikimedia.org/wikipedia/commons/1/19/Two-axis_gimbal.svg is a good candidate.
2. Instead of an infinite mass, a high mass cartridge. This is a compromise, but an inevitable one.
Third step:
1. Real joint: A gimbal (again).
2. A low mass cartridge but a rigid one, firmly attached to another higher mass support, so as to act (in terms of displacement) toward the cantilever pivot as if it has high mass. At this second attach point (and to each one in succession), again the Newton’s third law holds.
The whole idea is this: Every interface- be it a joint or an attachment- has to be fixed in space i.e. not move.
A non compliant joint or attachment method, plus a solid and rigid support is a good approximation of the ideal case.
We have to keep to this guide at the earliest point of the chain as much as possible
(Chain : Diamond tip to needle stem, needle stem to cantilever, cantilever to cantilever bearing, cantilever bearing to cartridge body, cartridge body to arm shell, arm shell to arm tube, arm tube to arm bearing, arm bearing to arm vertical body, arm vertical body to arm support, arm support to…).
The reason is that any relative motion there will introduce early modulations to the original signal, the results of which the human brain may not be able to distinguish from the original, just like what happens with the early reflections in the case of a loudspeaker in a room.
The engineer has finally to decide at which point in the chain he is allowed to introduce more compliant joint methods and materials.
My opinion is that the materialization of the cantilever bearing with an elastomer is a compromise placed too early in the chain. Furthermore the elastomer can not adequately restrict the unwanted fore-aft movement, nor some torsional momentums present in the cantilever.
(If you think of the fact that the cartridge cantilever assembly is a mechanical analougous to the turntable arm assembly, would you easily accept the bearing of the arm to be an elastomer mass?)
To be continued"
Regards
George
Triggered by haiteflon latest post, especially from the last sentence, here is the letter which I considered too long and too complicated back in my last post:
"Well, I will try to expand on my writing found in post#26 (page3).
I will start with a theoretical treatment of the subject (i.e. using some assumptions which later on will be dressed off their axiomatic clothes and exposed naked). Some drawings (attachment) may help.
All these forces invoke the 3dimentional movement of an assumed rigid and mass-less cantilever beam which is pivoted to an assumed infinite mass via an assumed loss-less 3dimentional ideal joint.
The result of this arrangement is that the other end of the beam where a mass-less magnet is attached to, follows precisely the movement of the needle according to the formulas that apply to a first class lever http://en.wikipedia.org/wiki/Lever#First-class_levers and assuming that no external forces act upon the magnet.
Now from the 3dimentional movement of the magnet, we would very much like to subtract the X axis (Fore-Aft) movement. So, we ask from the pivot joint to 100% transmit this movement to it’s (infinite mass) support.
At the pivot point(s) the Newton third law inevitably holds http://en.wikipedia.org/wiki/Newton's_laws_of_motion#Newton.27s_third_law:_law_of_reciprocal_actions , and it is applicable to all the forces acting on the beam.
It becomes clear why we would like the pivot support mass to be as large as possible and be as rigid as possible: If the mass and stiffness of the pivot support is infinite , the pivot point remains fixed in space.
The less of these qualities it possesses, the more the pivot moves in space.
If the pivot moves in space, this movement will modulate the movement of the needle which is transmitted (through the rigid cantilever) to the magnet. We don’t want this.
Let’s do the first step closer to reality now and deal with the:
1. Loss-less 3dimentional ideal joint: It has to induce as little friction as possible and have as little play as possible at the same time.
2. Infinite mass pivot support: Make it an infinite mass cartridge body.
Let’s do the second step:
1. Close to Ideal, but a real joint: A gimbal http://upload.wikimedia.org/wikipedia/commons/1/19/Two-axis_gimbal.svg is a good candidate.
2. Instead of an infinite mass, a high mass cartridge. This is a compromise, but an inevitable one.
Third step:
1. Real joint: A gimbal (again).
2. A low mass cartridge but a rigid one, firmly attached to another higher mass support, so as to act (in terms of displacement) toward the cantilever pivot as if it has high mass. At this second attach point (and to each one in succession), again the Newton’s third law holds.
The whole idea is this: Every interface- be it a joint or an attachment- has to be fixed in space i.e. not move.
A non compliant joint or attachment method, plus a solid and rigid support is a good approximation of the ideal case.
We have to keep to this guide at the earliest point of the chain as much as possible
(Chain : Diamond tip to needle stem, needle stem to cantilever, cantilever to cantilever bearing, cantilever bearing to cartridge body, cartridge body to arm shell, arm shell to arm tube, arm tube to arm bearing, arm bearing to arm vertical body, arm vertical body to arm support, arm support to…).
The reason is that any relative motion there will introduce early modulations to the original signal, the results of which the human brain may not be able to distinguish from the original, just like what happens with the early reflections in the case of a loudspeaker in a room.
The engineer has finally to decide at which point in the chain he is allowed to introduce more compliant joint methods and materials.
My opinion is that the materialization of the cantilever bearing with an elastomer is a compromise placed too early in the chain. Furthermore the elastomer can not adequately restrict the unwanted fore-aft movement, nor some torsional momentums present in the cantilever.
(If you think of the fact that the cartridge cantilever assembly is a mechanical analougous to the turntable arm assembly, would you easily accept the bearing of the arm to be an elastomer mass?)
To be continued"
Regards
George
Attachments
Zero One said: ..... I recalled one of the comments was that it would lead to less dynamics, now thinking about it perhaps what is interpreted as dynamics is actually vibration being fed back into the system, which would mean what is really being heard is a type of colouring of the sound rather than a true dynamic effect.
---Yes, this is what I think the case is in reality. George has evidently been focused on conserving as much energy as possible, but this energy is destructive if it is not in the proper place. The small amount of energy lost at some frequency is far less harmful than acoustic feedback.
Zero One said: A while back I wondered if the weight on the end of the tonearm could be better utilised, most are very solid and probably redirect a lot of energy back into the system, I thought that a weight that consisted of sand and leadshot might do a better job, though I have not got around to trying this.
----The mass of the tonearm is related to the low frequency resonance of the whole tonearm system. If the tonearm is too light this resonant frequency will be too high and record warps and lower bass will be distorted as the tonearm applies energy. One the other hand if a tonearm is too massive it becomes so sluggish that it stresses the cartridge suspension. I recall reading that the Technics 1200 manual direct drive was designed specifically for the Stanton 680 cartridge. The low freq resonance is 12Hz. This was probably for DJ applications where the whole building is vibrating.
Zero One said: I also have thought that most tonearms being some sort of tubular contruction are not perhaps the ideal approach, a non tubular wooden tonearm with light weight and carbon fibre or similar covering might be a lot better.
---I looked up the SME on the web last night. It is magnesium, $4500 worth of it. If you see a picture notice the shape of the arm. The diameter gets continually larger toward the bearing end. This may change the resonant frequency as the waves travel through the metal. This may be a type of damping (only an hypothesis). George may know about this. The Weathers tonearm in the 50s, super high-end at that time, was wood (not positive about this) as have been others in the past.
Zero One said: And while I'm on the subject, might bass dynamics actually be effected by having a tonearm that actually is too easily moved in the horizontal plane, many makers pride themselves on having main tonearm bearings with almost no resistance at all, but is this really a good thing?
----The bearings should be as quiet and frictionless as possible. They are very important and often dirty. What you are conceiving of is viscous damping. This is something the SME uses and is probably a very good addition to any tonearm.
Zero One said: Ah so many questions?
---Yes, and they get much worse when one considers that the tip of the stylus can get red hot. Also, the flexing of the vinyl is another type of acoustic feedback that talks to the feedback in the arm. The lower the mass of the stylus assembly the less significant these problems become, hopefully. It is notable that many of the finer cartridges have relatively low compliance. The higher the compliance the softer the elastomer bushing. This makes the stylus assembly more susceptible to the axial pull caused by friction. It tends to move the cantilever in and out. The anchor wire is there to stop it, so the energy probably causes a squirming motion. The motor (George’s energy pool) is so great in comparison to the energy needed to generate cartridge output that there is effectively no limit to the distortion that can be caused by axial pull on the cantilever. Please keep in mind that I am not professing to know all of this for sure. It is my concept of the situation thus far. Also, the polish on the diamond is very important. A “grain-oriented” diamond is evidently a diamond that is positioned so that it can be polished very well. Much to learn.
---Yes, this is what I think the case is in reality. George has evidently been focused on conserving as much energy as possible, but this energy is destructive if it is not in the proper place. The small amount of energy lost at some frequency is far less harmful than acoustic feedback.
Zero One said: A while back I wondered if the weight on the end of the tonearm could be better utilised, most are very solid and probably redirect a lot of energy back into the system, I thought that a weight that consisted of sand and leadshot might do a better job, though I have not got around to trying this.
----The mass of the tonearm is related to the low frequency resonance of the whole tonearm system. If the tonearm is too light this resonant frequency will be too high and record warps and lower bass will be distorted as the tonearm applies energy. One the other hand if a tonearm is too massive it becomes so sluggish that it stresses the cartridge suspension. I recall reading that the Technics 1200 manual direct drive was designed specifically for the Stanton 680 cartridge. The low freq resonance is 12Hz. This was probably for DJ applications where the whole building is vibrating.
Zero One said: I also have thought that most tonearms being some sort of tubular contruction are not perhaps the ideal approach, a non tubular wooden tonearm with light weight and carbon fibre or similar covering might be a lot better.
---I looked up the SME on the web last night. It is magnesium, $4500 worth of it. If you see a picture notice the shape of the arm. The diameter gets continually larger toward the bearing end. This may change the resonant frequency as the waves travel through the metal. This may be a type of damping (only an hypothesis). George may know about this. The Weathers tonearm in the 50s, super high-end at that time, was wood (not positive about this) as have been others in the past.
Zero One said: And while I'm on the subject, might bass dynamics actually be effected by having a tonearm that actually is too easily moved in the horizontal plane, many makers pride themselves on having main tonearm bearings with almost no resistance at all, but is this really a good thing?
----The bearings should be as quiet and frictionless as possible. They are very important and often dirty. What you are conceiving of is viscous damping. This is something the SME uses and is probably a very good addition to any tonearm.
Zero One said: Ah so many questions?
---Yes, and they get much worse when one considers that the tip of the stylus can get red hot. Also, the flexing of the vinyl is another type of acoustic feedback that talks to the feedback in the arm. The lower the mass of the stylus assembly the less significant these problems become, hopefully. It is notable that many of the finer cartridges have relatively low compliance. The higher the compliance the softer the elastomer bushing. This makes the stylus assembly more susceptible to the axial pull caused by friction. It tends to move the cantilever in and out. The anchor wire is there to stop it, so the energy probably causes a squirming motion. The motor (George’s energy pool) is so great in comparison to the energy needed to generate cartridge output that there is effectively no limit to the distortion that can be caused by axial pull on the cantilever. Please keep in mind that I am not professing to know all of this for sure. It is my concept of the situation thus far. Also, the polish on the diamond is very important. A “grain-oriented” diamond is evidently a diamond that is positioned so that it can be polished very well. Much to learn.
Beam me up, Scotty.
Ah, the sterile idealism of the engineering classroom. Virtual perfection on a purple velvet pillow. More gold stars on George’s forehead. Cum Laude, Cum Laude
Let’s take the simple approach. You draw up the matrices and I will go through them and erase everything I don’t like and put an M&M there. You can pick the colors. Welcome to Candyland.
I don’t know whether I like the mass-less magnets or the gimbaled suspension the best.
Ever seen an old Decca cartridge with no cantilever?
What we have in reality is a tube in a rubber fulcrum with unequal lengths and masses on either side of the fulcrum. To further complicate the matter there is a modulating torque on the cantilever due to the fact that the diamond is contacting the groove at a distance from the cantilver. We won’t concern ourselves with static electricity generated by dirt.
It is amazing that a phonograph record works as well as it does.
The engineer of a single component (say a cartridge) intended for the consumer market, has to design it in a way that it is a good fit to various systems.
The purchaser of such a product is able to “trim” it for optimum match with his (her) particular system.
The designer of a system does have the luxury and the responsibility to match every component.
To Mark
My intention was to lay down the bare facts, for to become obvious where and why some things have to be compromised. Then, dealing with the existing compromises, to see if an alternative compromise - more promising for each particular case - can be chosen.
Sterile Analysis and Synthesis approach, versus Intuitive approach.
Intuitively chosen solutions may very well be the correct solutions for the particular system to which they have been applied (educated intuition), but may be erroneously regarded as a correct solution for every system (just an intuition).
For the rest of your post, see my post#42 (line 11 and below).
My psycho pathetic profile forces me to withdraw back into my shell.
I am a pigeon.
Save all the gold stars for the fighters.
Regards
George Papageorgiou
crash and burn
Sorry George, I didn’t think that you were totally serious.
You didn’t give me my test score in bicycle generators 101 so I thought this was a pop quiz to get even for my having aced the first test.
How many choices does an engineer have in cartridge design?
It is what it is. Mark
Sorry George, I didn’t think that you were totally serious.
You didn’t give me my test score in bicycle generators 101 so I thought this was a pop quiz to get even for my having aced the first test.
How many choices does an engineer have in cartridge design?
It is what it is. Mark
I told you that I agree with you, but we may be both wrong.
A. Consider the disciplines involved:
I. In the design, prototyping and testing stages:
Classic Mechanics (Statics, dynamics,), Electrism, Magnetism, Acoustics, Vibration Analysis, Material Science, Industrial design.
II. In forwarding his (her) design through the financial department:
Statistics, Financing, Management, Games Theory, Applied Psychology.
III. In convincing the BoD for the merits of this new product:
Games theory (strip poker tactics).
B. Start counting.
Regards
George Papageorgiou
is this possible?
George, I'm running out of forum time, but I do want to see what ZeroOne does with his project.
You said a few days ago, to another poster.
"Now, that was a good blow.
After half an hour been lying down half unconscious, I called my lawyer and he told me there is little I can do to defend my case in the court. It might be beneficial though if I could formulate a text listing my strong and weak points. So, I thought of the following:"
I didn't think it was possible at first, but now it appears that you are trying to file some sort of insane lawsuit about your hurt feelings. Forgot to open that retirement fund?
You keep bringing up all this nonsense in a seemingly obvious attempt to get someone to call you a name.
You made the whole bit up about the 2.7db increase didn't you?
I've had enough of this. Mark
George, I'm running out of forum time, but I do want to see what ZeroOne does with his project.
You said a few days ago, to another poster.
"Now, that was a good blow.
After half an hour been lying down half unconscious, I called my lawyer and he told me there is little I can do to defend my case in the court. It might be beneficial though if I could formulate a text listing my strong and weak points. So, I thought of the following:"
I didn't think it was possible at first, but now it appears that you are trying to file some sort of insane lawsuit about your hurt feelings. Forgot to open that retirement fund?
You keep bringing up all this nonsense in a seemingly obvious attempt to get someone to call you a name.
You made the whole bit up about the 2.7db increase didn't you?
I've had enough of this. Mark
As the poster in question, I assure you that George was showing his usual sense of humor. And I thought it was damn funny.
Now just to keep things on topic here I have a couple of comments, questions.
I mentioned that I have wondered about the bass being effected by the tone arm being too easily moved in the lateral dimension, I should have added that a while back I did apply a mod that seems to work well on my TT along these lines.
Due to my concern over bearing chatter in the horizontal arm bearing I added a weight over the pivot point, it is made from polished alloy, I found this improved things a lot but it also improved bass, I felt that the extra inertia required to rotate the weight loaded arm may have cuased the arm to be unmoved by the smaller scale movementsof riding the bass modulations whilst having no effect on the ability of the arm to move with large scale movements such as tracking a non concentric groove. I imagine fliud damping does just this and maybe I got lucky, but it really does seem to work so much better.
Thinking further about the issue of stylus moving in and out during playing, I looked at the stylus in my modding cart, now basically it is a smooth shaft, so I wonder if notching the shaft very lightly at the point where it interfaces with the inner and outer lip of the elastomer may help......eye straining stuff but I think I can manage it. I imagine the lip of the elastomer would tighten itself into the notch which would make a more positive bond, this would not of course help with any movement in the elastomer, I'm still thinking about that one.
Considering the nature of vibrations and the way in which different materials filter different frequencies perhaps the ideal design for a cart body is one that has several different layers of differing materials? As to what those materials should be I don't know.
Thinking further on Georges original post, it would seem to me that the closer the source the control can be the better the result, having now looked at a number of cart I have here is seems the interface between the cart and stylus holder is typically poor, lots of flat surfeces of hard material but with little mass and small cavity in and around the fitting. One of the first things I experimented with was bluetacing the stylus holder in place, it worked a treat but now I am starting to see why.
Another little issue I am wondering is the attachment of the magnet to the stylus, having looked at the one I am working on it really does not look at all secure, I imagine it would be subject to vibration and in this position it would have a huge effect on the sound, what about a small film of super glue or even PVA, or perhaps even a coat of laquer that drips into the joint between the magnet and tube?
Ah the questions just keep coming.
Zero One
I mentioned that I have wondered about the bass being effected by the tone arm being too easily moved in the lateral dimension, I should have added that a while back I did apply a mod that seems to work well on my TT along these lines.
Due to my concern over bearing chatter in the horizontal arm bearing I added a weight over the pivot point, it is made from polished alloy, I found this improved things a lot but it also improved bass, I felt that the extra inertia required to rotate the weight loaded arm may have cuased the arm to be unmoved by the smaller scale movementsof riding the bass modulations whilst having no effect on the ability of the arm to move with large scale movements such as tracking a non concentric groove. I imagine fliud damping does just this and maybe I got lucky, but it really does seem to work so much better.
Thinking further about the issue of stylus moving in and out during playing, I looked at the stylus in my modding cart, now basically it is a smooth shaft, so I wonder if notching the shaft very lightly at the point where it interfaces with the inner and outer lip of the elastomer may help......eye straining stuff but I think I can manage it. I imagine the lip of the elastomer would tighten itself into the notch which would make a more positive bond, this would not of course help with any movement in the elastomer, I'm still thinking about that one.
Considering the nature of vibrations and the way in which different materials filter different frequencies perhaps the ideal design for a cart body is one that has several different layers of differing materials? As to what those materials should be I don't know.
Thinking further on Georges original post, it would seem to me that the closer the source the control can be the better the result, having now looked at a number of cart I have here is seems the interface between the cart and stylus holder is typically poor, lots of flat surfeces of hard material but with little mass and small cavity in and around the fitting. One of the first things I experimented with was bluetacing the stylus holder in place, it worked a treat but now I am starting to see why.
Another little issue I am wondering is the attachment of the magnet to the stylus, having looked at the one I am working on it really does not look at all secure, I imagine it would be subject to vibration and in this position it would have a huge effect on the sound, what about a small film of super glue or even PVA, or perhaps even a coat of laquer that drips into the joint between the magnet and tube?
Ah the questions just keep coming.
Zero One
To all of us:
"Sir, What is the secret of your success?"
"Two words"
"And, Sir, what are they?"
"Right decisions."
"And how do you make right decisions?"
"One word."
"And, What is that?"
"Experience."
"And how do you get Experience?"
"Two words"
"And, Sir, what are they?"
"Wrong decisions."
(Version due to Jacques Barber)
Mark,
If reasoning implications is this that you are referring to, this is something that you may find amusing (You are not alone. We are all stepping on it):
Rap song inspired by "Thinking and deciding"
I woke up and had a revelation
Correlation does not imply causation.
The situation is quite terrible
When you've got a confounding variable.
Another reason to think carefully:
Does B cause A or does A cause B?
Popper said "I wonder why?
Einstein's theory lived but Freud's has died.
It seems to me the difference is
That Einstein's could be falsified."
Suppose one day I say to you,
"Hey listen up: 'If p, then q!'"
And then I tell you: "p is true."
Could you be sure that q's true too?
And what if I'd said: "q is true."
Could you conclude that p's true too?"
[Not you again!]
That's right! It's me!
Is it "not q" if it's "not p?"
[Please go away!]
One more to do!
Is it "not p" if it's "not q?"
Peter Wason is the name
Of a man who liked card games.
But unlike me and unlike you
He played with four, not fifty-two.
Letters on the front
Numbers on the back.
"A" and "B" and "2" and "3"
Are all that you can see.
A rule has been proposed.
You don't know if it's true.
"A card that has a vowel
Has an even number too."
Which cards must you inspect
To verify the rule?
[Why not check them all?]
No, that would not be cool!
You've got to check the A
(Don't bother with the B)
The 2 can't give you trouble
But watch out for the 3!
Doc Wason's back
He's got more tricks
Here's a game
Called 2-4-6.
Your job is to name sets of three
To test different hypotheses.
[3-6-9?]
Yes!
[1-2-3?]
Well that works too.
[I'm smart as you!]
[6-8-10?]
Way to go, my friend!
[3-2-1?]
No! Please try again.
[10-12-14?]
That's peachy keen!
[2-3-4?]
Oy, how many more?
[1-2-10?]
Yes! We're near the end!
[5-6-8?]
Right! You're doing great!
I'm ready, now. I can guess your rule.
I'm the one that you cannot fool.
The rule you use for sets of three:
Increasing numerosity!
Deborah Frisch (Penn PhD)
You can call me a name.
Regardless of my reaction, it will do me good. (this is actually what an interpersonal relationship is all about).
Yes, and then I switched to the “why and how does this happened” mode.
Because either this mode or the way I am expressing it, is unpleasant to you, I will stop it. This is a public place and not my own territory.
SY
Just a very small sample of the different facets of humour (psychoanalytical approach):
Nachdenkliche Heiterkeit: By Theodor Reik. (Internationaler Psychoanalytischer Verlag, Vienna, 1933. Pp. 183. Price, R.M. 5.50.)
Review by: E. Kris
This work is devoted to the 'realm of the comic', which is 'as extensive as the domain of tragedy' and more so, ranging 'from joking which reviles to humour which reconciles' (p. 5); it consists of fifteen studies of varying range, which, grouped in three divisions ('Borderline Problems of Joking', 'Jest becomes Earnest' and 'Between Horror and Laughter'), have yet 'unpretentiously though firmly rejected every attempt at orderly arrangement' (p. 90). They include penetrating monographs, such as that on the 'Intimacies of Jewish Jokes' (the depreciatory tendencies of which Reik attributes to the influence of the need for punishment), brilliant notes, in one of which, for example, slips of the tongue occurring in jokes are regarded as 'a bridge between failure and achievement in function', and short essays, some of them only loosely connected with the author's theme, but linking on to other earlier work of his, and completing and expanding the lines of thought there developed.
Back to cartridges.
Some 5-6 days ago in my sleep I had a dream.
There was a 3dimentional rotating image of a “ wafer” into which, two flat coils and a part of a bearing housing were micro-etched.
When I woke up, my impression was that this is part of a cartridge assembly.
The feeling was a very relaxing one.
The interesting point about this image was that, it was shown in green colour. Does this mean that Morphaeus hinted toward the use of green monochromatic light for the lithographic process ( green light has a wavelength of ~510nm)?
Zero one
Keep up moding!
What do you mean by “stylus holder”?
The rest of your observations are valuable.
Regards
George Papageorgiou
"Sir, What is the secret of your success?"
"Two words"
"And, Sir, what are they?"
"Right decisions."
"And how do you make right decisions?"
"One word."
"And, What is that?"
"Experience."
"And how do you get Experience?"
"Two words"
"And, Sir, what are they?"
"Wrong decisions."
(Version due to Jacques Barber)
Mark,
If reasoning implications is this that you are referring to, this is something that you may find amusing (You are not alone. We are all stepping on it):
Rap song inspired by "Thinking and deciding"
I woke up and had a revelation
Correlation does not imply causation.
The situation is quite terrible
When you've got a confounding variable.
Another reason to think carefully:
Does B cause A or does A cause B?
Popper said "I wonder why?
Einstein's theory lived but Freud's has died.
It seems to me the difference is
That Einstein's could be falsified."
Suppose one day I say to you,
"Hey listen up: 'If p, then q!'"
And then I tell you: "p is true."
Could you be sure that q's true too?
And what if I'd said: "q is true."
Could you conclude that p's true too?"
[Not you again!]
That's right! It's me!
Is it "not q" if it's "not p?"
[Please go away!]
One more to do!
Is it "not p" if it's "not q?"
Peter Wason is the name
Of a man who liked card games.
But unlike me and unlike you
He played with four, not fifty-two.
Letters on the front
Numbers on the back.
"A" and "B" and "2" and "3"
Are all that you can see.
A rule has been proposed.
You don't know if it's true.
"A card that has a vowel
Has an even number too."
Which cards must you inspect
To verify the rule?
[Why not check them all?]
No, that would not be cool!
You've got to check the A
(Don't bother with the B)
The 2 can't give you trouble
But watch out for the 3!
Doc Wason's back
He's got more tricks
Here's a game
Called 2-4-6.
Your job is to name sets of three
To test different hypotheses.
[3-6-9?]
Yes!
[1-2-3?]
Well that works too.
[I'm smart as you!]
[6-8-10?]
Way to go, my friend!
[3-2-1?]
No! Please try again.
[10-12-14?]
That's peachy keen!
[2-3-4?]
Oy, how many more?
[1-2-10?]
Yes! We're near the end!
[5-6-8?]
Right! You're doing great!
I'm ready, now. I can guess your rule.
I'm the one that you cannot fool.
The rule you use for sets of three:
Increasing numerosity!
Deborah Frisch (Penn PhD)
You can call me a name.
Regardless of my reaction, it will do me good. (this is actually what an interpersonal relationship is all about).
Yes, and then I switched to the “why and how does this happened” mode.
Because either this mode or the way I am expressing it, is unpleasant to you, I will stop it. This is a public place and not my own territory.
SY
Just a very small sample of the different facets of humour (psychoanalytical approach):
Nachdenkliche Heiterkeit: By Theodor Reik. (Internationaler Psychoanalytischer Verlag, Vienna, 1933. Pp. 183. Price, R.M. 5.50.)
Review by: E. Kris
This work is devoted to the 'realm of the comic', which is 'as extensive as the domain of tragedy' and more so, ranging 'from joking which reviles to humour which reconciles' (p. 5); it consists of fifteen studies of varying range, which, grouped in three divisions ('Borderline Problems of Joking', 'Jest becomes Earnest' and 'Between Horror and Laughter'), have yet 'unpretentiously though firmly rejected every attempt at orderly arrangement' (p. 90). They include penetrating monographs, such as that on the 'Intimacies of Jewish Jokes' (the depreciatory tendencies of which Reik attributes to the influence of the need for punishment), brilliant notes, in one of which, for example, slips of the tongue occurring in jokes are regarded as 'a bridge between failure and achievement in function', and short essays, some of them only loosely connected with the author's theme, but linking on to other earlier work of his, and completing and expanding the lines of thought there developed.
Back to cartridges.
Some 5-6 days ago in my sleep I had a dream.
There was a 3dimentional rotating image of a “ wafer” into which, two flat coils and a part of a bearing housing were micro-etched.
When I woke up, my impression was that this is part of a cartridge assembly.
The feeling was a very relaxing one.
The interesting point about this image was that, it was shown in green colour. Does this mean that Morphaeus hinted toward the use of green monochromatic light for the lithographic process ( green light has a wavelength of ~510nm)?
Zero one
Keep up moding!
What do you mean by “stylus holder”?
The rest of your observations are valuable.
Regards
George Papageorgiou
Hi George
By stylus holder I mean the usual plastic assembly that holds the cantilever and diamond that is then pushed into the body of the cart, I suppose most folk refer to the whole assembly as the stylus.
By stylus holder I mean the usual plastic assembly that holds the cantilever and diamond that is then pushed into the body of the cart, I suppose most folk refer to the whole assembly as the stylus.
Something 's telling me that what George actually did with his cartridge,is something like welding shock absorbers in a car's suspension just because they moved,and left all the job to be done by the coil springs.The designer of the car suspension,either he didn't know that he should have welded the shock absorbers,or,he simply didn't want to.Maybe he knew that by welding them,he would have to deal with say a 2.7db or 27db resonance peak somewhere else?So,I guess in the end he has rightly chosen not to weld the shock absorbers,as he knew that it was less of a compromise if they moved,than not to.
A little update on the issue of securing the cantilever so it is less likely to pull forward on heavy modulations, I suggested notching the cantilever, I think this will still work Ok as I tried it on one of the same carts that had a busted magnet, it is more secure if you use tiny pliers to pull against the cantilever it can be seen clearly......but
I have found that I can actually wind one turn of very very fine copper wire around the cantilever shaft at the point where it mates with the elasmoter and use a dab of super glue to stick it there, then trim the excess and slide the elastomer back tot he right position, this should work better I feel, it does not look as though it will effect anything else. Having tried this on a sacrificial cantilever I think I can go forth on the real thing.
Going further the front of the elastomer (ie the bit facing the record) can also move slightly forward under pressure, this I think can be locked in place better but I am still looking at this issue.
I hope to have this cart finished over the weekend.
I have found that I can actually wind one turn of very very fine copper wire around the cantilever shaft at the point where it mates with the elasmoter and use a dab of super glue to stick it there, then trim the excess and slide the elastomer back tot he right position, this should work better I feel, it does not look as though it will effect anything else. Having tried this on a sacrificial cantilever I think I can go forth on the real thing.
Going further the front of the elastomer (ie the bit facing the record) can also move slightly forward under pressure, this I think can be locked in place better but I am still looking at this issue.
I hope to have this cart finished over the weekend.
audio technica
Zero One: Audio Technica does not use an anchor wire. They put the magnets in view (you have probably seen them when looking at an AT stylus). There is a little screw that holds the cantilever assembly in. It pulls out when the screw is loosened. There appears to be no anchor wire, nothing but rubber. There is no elastomer bushing, only a rubber block.
It takes such a small disruptuion of the proper path of the stylus to cause distortion that any attempt to secure the cantilever from the rear is probably a waste of time.
A technical problem with the LP is the inner grooves. The linear velocity gets very slow and the wave lengths get very steep. This is where the axial pull is greatest on the cantilever.
As a matter of interest: I found a new Supertrack type III elliptical stylus on the floor of a warehouse. It had been stepped on. The diamond-shaped tube was damaged, but the stylus and cantilever were untouched. I also found a phoney aftermarket ElectroVoice Supertrack replacement stylus that had a broken cantilever, but a good tube. I put the real cantilever/stylus in the aftermarket tube with silicone gasketmaker, just to see what would happen.
The compliance is very low, but it sounds surprisingly good. I think what is going on is that the highly polished real Supertrack elliptical diamond is a very important component in the overall performance of the Supertrack, or any cartridge for that matter.
Zero One: Audio Technica does not use an anchor wire. They put the magnets in view (you have probably seen them when looking at an AT stylus). There is a little screw that holds the cantilever assembly in. It pulls out when the screw is loosened. There appears to be no anchor wire, nothing but rubber. There is no elastomer bushing, only a rubber block.
It takes such a small disruptuion of the proper path of the stylus to cause distortion that any attempt to secure the cantilever from the rear is probably a waste of time.
A technical problem with the LP is the inner grooves. The linear velocity gets very slow and the wave lengths get very steep. This is where the axial pull is greatest on the cantilever.
As a matter of interest: I found a new Supertrack type III elliptical stylus on the floor of a warehouse. It had been stepped on. The diamond-shaped tube was damaged, but the stylus and cantilever were untouched. I also found a phoney aftermarket ElectroVoice Supertrack replacement stylus that had a broken cantilever, but a good tube. I put the real cantilever/stylus in the aftermarket tube with silicone gasketmaker, just to see what would happen.
The compliance is very low, but it sounds surprisingly good. I think what is going on is that the highly polished real Supertrack elliptical diamond is a very important component in the overall performance of the Supertrack, or any cartridge for that matter.
Gday Hailteflon
I managed to get the wire ring around the cantilever and I have checked all the clearances etc all is fine so I am pretty confident it will work, it is truly a tiny addition but enough I think to better control the cantilever, if it bombs out its no problem I have another stylus.
I have filed down the excess metal around the stylus tip, (I have done this on another modded cart of the same model and it worked a treat, much nicer high end extension), the magnet is glued nicely in place and the shielding has been made for the cart and all the internal bits are nicely together.
Overall if the whole thing fails it is not going to make me cry it has cost me only $10.00 all up and if it works well I will be very happy, either way I will have learnt a lot about cart design and performance!
Thanks for advice, I will keep you posted, sorry no pics of the stylus assembly it is just too small for the camera gear I have even on maximum macro.
Your comments about the inner grooves are helpful as the lowering of inner groove distortion was one of the biggest side benefits I had as a result of gluing the stylus in on the previous carts and using the foam mounting, more thought on this is justified I reckon.
I managed to get the wire ring around the cantilever and I have checked all the clearances etc all is fine so I am pretty confident it will work, it is truly a tiny addition but enough I think to better control the cantilever, if it bombs out its no problem I have another stylus.
I have filed down the excess metal around the stylus tip, (I have done this on another modded cart of the same model and it worked a treat, much nicer high end extension), the magnet is glued nicely in place and the shielding has been made for the cart and all the internal bits are nicely together.
Overall if the whole thing fails it is not going to make me cry it has cost me only $10.00 all up and if it works well I will be very happy, either way I will have learnt a lot about cart design and performance!
Thanks for advice, I will keep you posted, sorry no pics of the stylus assembly it is just too small for the camera gear I have even on maximum macro.
Your comments about the inner grooves are helpful as the lowering of inner groove distortion was one of the biggest side benefits I had as a result of gluing the stylus in on the previous carts and using the foam mounting, more thought on this is justified I reckon.
It would be nice to have some pics. Not sure how much you have constructed yourself.
Joe Grado was a jeweler before he went into the cart business. He wrote a series of articles about tonearms etc. If I find them on the web I will post the link. He used to sell a wooden tonearm.
My next stop on the web is Toys-R-Us to shop for a childrens digital microscope. Supposedly they will magnify enough to check a stylus for wear.
I'll check for Joe's articles first. He made his high end carts personally, as I recall. He had all the little parts in plastic drawers.
One good thing about a conical stylus is that they are the same from every direction. They also distribute the force on the vinyl over a very large area. Sort of like a line-contact, but horizontally. I have found that they often do a better job on the inner grooves.
There is an article on the Van Den Hull website about an inherent geometric flaw in the elliptical stylus. I need to read it thoroughly. I glanced at it once. It does make sense.
Joe Grado was a jeweler before he went into the cart business. He wrote a series of articles about tonearms etc. If I find them on the web I will post the link. He used to sell a wooden tonearm.
My next stop on the web is Toys-R-Us to shop for a childrens digital microscope. Supposedly they will magnify enough to check a stylus for wear.
I'll check for Joe's articles first. He made his high end carts personally, as I recall. He had all the little parts in plastic drawers.
One good thing about a conical stylus is that they are the same from every direction. They also distribute the force on the vinyl over a very large area. Sort of like a line-contact, but horizontally. I have found that they often do a better job on the inner grooves.
There is an article on the Van Den Hull website about an inherent geometric flaw in the elliptical stylus. I need to read it thoroughly. I glanced at it once. It does make sense.
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