This is beautiful work and I,m sure it will work of course, but, at the end of the day will it really sound any better or maybe not as good as frictionless air bearing with mass and rigidly coupled at the headshell ala ET1or ET2?
an arm like the ET, the typical air bearing arm, depends on the side pressure from the stylus to control the left/right movement of the arm. Then you have the mass of the arm, and the inertia to overcome... the straight line tracker tries to place these forces in the axis that is 90 degrees from the left/right, in line... the issue then is one of overshoot/undershoot. That may or may not be a practical issue. It remains to be seen.
At least this is how I see it so far... interesting idea. 😀
_-_-bear
At least this is how I see it so far... interesting idea. 😀
_-_-bear
The downside I see hear is the pivots right at the foundation where you want a rigid platform to control any contributing vibrations. Trying to find bearings that are tight enough and at the same time frictionless in this critical junction seems impossible to control effectively. We have read how reviewers have a certain disdain about removable headshells and how it affects the end result no matter the efforts to make a rigid platform. This is what raises the concern here
That's where a design like the Versa dynamics made so much sense. Small rigid platforms and frictionless to boot.
Of course it required a whole set of other design decisions to control warps.
I guess in the pivoting SLTr you would want to use high compliance carts just inside the mass of the arm to limit any outside issues popping up.
We await an unbiased listening result of your efforts since you have certainly put alot of time thinking and building a passion!
That's where a design like the Versa dynamics made so much sense. Small rigid platforms and frictionless to boot.
Of course it required a whole set of other design decisions to control warps.
I guess in the pivoting SLTr you would want to use high compliance carts just inside the mass of the arm to limit any outside issues popping up.
We await an unbiased listening result of your efforts since you have certainly put alot of time thinking and building a passion!
I think you're are still mistaken Straight Tracker's design as an ACTIVE system, like that of Rabco or Goldmund that's motorized and it is always "hunting" for tangency, hence the overshoot or undershoot issue. It's actually a PASSIVE system not much different from the ET arm, except it doesn't travel horizontally but in an arc that's governed by the geometry of the Thales semi-circle (or at least geometry that's close to it), that is one angle of a triangle inside a semi-circle is always 90°.
Mechanically, it's closer to designs like Clearaudio or Souther, that is, it glides on rollers, and the Straight-Tracker arm is on a wagon on fixed curved rails. The rails are forcing or guiding the carriage to travel in a way that the stylus is always tangent to the center of the record. Once you understand the Thales theory and how the Thales tonearm works, you'll know Ralf's design is to shift the extra pivot point to the base of the arm instead of at the headshell.
Will it work and sound as good as traditional airbearing tonearm? It will depend on the quality of the bearings and the precision of the tracks and if they're warranted then at least in theory the arm can sound as good or better than traditional airbearing design in overcoming the horizontal mass.
I look forward to seeing more pictures and sound reports. If nothing else, at least we have a think-outside-of-the-box design and that's admirable to me.
.
I did not say it is active. The designer said that he intended the arm to be dragged by the friction of the stylus on the record, more or less forward... afaik the rails are not curved at all... look again.
So, the issue is once it gets moving "forward" will it try to keep going, and if not, will it stop for "too long" causing alternate mistracking between the too far forward and the too far back position...
Otoh, the original design patent does call for an active motor to run the arm on the carriage...
But I would prefer if the designer would field these questions, I am really only asking them, not trying to answer them.
_-_-bear
So, the issue is once it gets moving "forward" will it try to keep going, and if not, will it stop for "too long" causing alternate mistracking between the too far forward and the too far back position...
Otoh, the original design patent does call for an active motor to run the arm on the carriage...
But I would prefer if the designer would field these questions, I am really only asking them, not trying to answer them.
_-_-bear
You're right. What I meant to say is the trajectory (vector?) curved, not the track. As the arm gets closer to the center the arm gets "longer," the distance between pivot point of the armbase to the stylus. And if you draw a line at the center of the carriage as the arm moves from outside of the record to the inside, it is a curve. Sorry for the factual error.
Since it's a passive system, it's really no different dynamically from an airbearing arm, or even a pivot arm, as far as my understanding. The stylus simply follows the groove and on off center records the arm will swing accordingly back and forth. What the design needs to overcome is to keep horizontal mass minimum, at least have to be less than an airbearing arm otherwise there would be no point of it. Low friction and geometric precision are mandatory, of course. The bottomline is that since it's not a servo system, there's no overshoot or undershoot to detect or to correct. It simply follows the groove like most arms.
Ralf mentioned a motorized version but this one is purely mechanical. I look forward to his response.
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Hello gninnam,
sofar there is no news.
I opened a can of worms when I built that tone arm. My Hi-Fi system had gotten into disrepair over the years and I am currently getting that taken care of. The woofer cones of my Koss speakers had turned to dust in the Arizona air. I just purchased a pair of Polk book shelf speakers and now I have to clean the volume control of my Pioneer SA-1000 amplifier.
However, it won't be long now.
Sincerely,
Ralf
sofar there is no news.
I opened a can of worms when I built that tone arm. My Hi-Fi system had gotten into disrepair over the years and I am currently getting that taken care of. The woofer cones of my Koss speakers had turned to dust in the Arizona air. I just purchased a pair of Polk book shelf speakers and now I have to clean the volume control of my Pioneer SA-1000 amplifier.
However, it won't be long now.
Sincerely,
Ralf
Hello Sbe
I agree that the improvements I claim, might not be audible when I get done. But it is fun to know that I may have created a perfect tone arm. I have a lot of experimenting to do before I find that out.
Sincerely,
Ralf
I agree that the improvements I claim, might not be audible when I get done. But it is fun to know that I may have created a perfect tone arm. I have a lot of experimenting to do before I find that out.
Sincerely,
Ralf
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Hello Sbe,
I'm afraid, that none of the available tangential tone arms have a rigid base for their pivots. I have designed the carriage of my tone arm in such a way, that all the bearings involved with its motion are preloaded by gravity. In other words, none of the bearings have any looseness. As everyone knows, a preloaded bearing exibits the least friction.The bearings for horizontal and vertical motion are free-flex pivots which have no friction and no free play.
Sincerely,
Ralf
I'm afraid, that none of the available tangential tone arms have a rigid base for their pivots. I have designed the carriage of my tone arm in such a way, that all the bearings involved with its motion are preloaded by gravity. In other words, none of the bearings have any looseness. As everyone knows, a preloaded bearing exibits the least friction.The bearings for horizontal and vertical motion are free-flex pivots which have no friction and no free play.
Sincerely,
Ralf
Hello bear, Hello directdriver,
when you let too many posts accumulate before you answer them it gets difficult to keep things straight. Tax day delayed my response. Tax day is a chaotic mess in my house.
To drive my tone arm purely with the frictional pulling force of the LP has been a dream of mine for a long time. I was never 100% sure as to wether that would actually work. That is why I've provided space in the base of my tone arm for a stepping motor and a lead screw. Frank Schröder, whom I met at the CES in Las Vegas in February told me that he would be "deeply impressed" if that idea actually worked. Tests I've conducted so far clearly show that the LP can easily pull the carriage and tone arm. What I am trying to do now is to design an opposing force that is always equal and opposite to the pulling force of the LP. In a future post I'll try to illustrate that with some more drawings.
Sincerely,
Ralf
when you let too many posts accumulate before you answer them it gets difficult to keep things straight. Tax day delayed my response. Tax day is a chaotic mess in my house.
To drive my tone arm purely with the frictional pulling force of the LP has been a dream of mine for a long time. I was never 100% sure as to wether that would actually work. That is why I've provided space in the base of my tone arm for a stepping motor and a lead screw. Frank Schröder, whom I met at the CES in Las Vegas in February told me that he would be "deeply impressed" if that idea actually worked. Tests I've conducted so far clearly show that the LP can easily pull the carriage and tone arm. What I am trying to do now is to design an opposing force that is always equal and opposite to the pulling force of the LP. In a future post I'll try to illustrate that with some more drawings.
Sincerely,
Ralf
Hello bear,
Of course. You are right.
I think that mistake was based on wishful thinking.
There are three events spanning January and February in Las Vegas every year: The SHOT SHOW, The Beinfeld Antique Arms Show and the CES. I can afford only one of them per year.
Sicerely,
Ralf
Of course. You are right.
I think that mistake was based on wishful thinking.
There are three events spanning January and February in Las Vegas every year: The SHOT SHOW, The Beinfeld Antique Arms Show and the CES. I can afford only one of them per year.
Sicerely,
Ralf
You might try changing one of the arm tubes to a different size so any high Q resonances will not magnify themselves. Carbon fiber seems like the best material but has serious peaks that add a flavor to the sound you don,t want. I see you have done some work to attack this area. You might have to dampen more than you stated. Putting shrink wrap may ruin the look but do wonders along with expandable foam internally.
The "Base" I was referring to earlier meant the cartridge platform and those pivots of concern. What happens right there will make or break what colorations add up in the end. you don't want the cantilever competing with anything else!
Sounds like a great challenge anyway!
The "Base" I was referring to earlier meant the cartridge platform and those pivots of concern. What happens right there will make or break what colorations add up in the end. you don't want the cantilever competing with anything else!
Sounds like a great challenge anyway!
Great workmanship and a design tour de force, straighttracker. I sincerely hope it all comes together soon. Your machinework on your mill leaves my tinkerings on my Myford and Maximat abolutely in the dust😱
Besides listening tests, will you have access to test records for checking channel separation and tracking and perhaps an accelerometer for arm vibration?
I am another Micro Seiki owner (Micro MR-711 and a BL-51) and your deck is a fitting testbed for your endeavours.
Regards and much admirations from Cape Town.
bulgin
Besides listening tests, will you have access to test records for checking channel separation and tracking and perhaps an accelerometer for arm vibration?
I am another Micro Seiki owner (Micro MR-711 and a BL-51) and your deck is a fitting testbed for your endeavours.
Regards and much admirations from Cape Town.
bulgin
Hi Ralf,
WOW, what a work. I feel completely ridiculous with my small little, minuscule TT project.
I'm trying to practice mecanical work while you're micromecanical working.
Design is also beautiful, I'll get inspiration for my new tonearm.
THANKS for this post
Bruno
WOW, what a work. I feel completely ridiculous with my small little, minuscule TT project.
I'm trying to practice mecanical work while you're micromecanical working.
Design is also beautiful, I'll get inspiration for my new tonearm.
THANKS for this post
Bruno
No update since August, please don't keep us in suspense; does it work as a 'passive' device? or have you added a servo?
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