Chuck911 said "The changes heard in my system (and this is by me, Chris did not have the time to A/B this) were towards a more lively, dynamic presentation."
Just a thought, but perhaps what Chris perceived as "added hardness" in another system translates directly to what you heard.
After all, you are using a relatively low powered tubed integrated amp (or were at the time of the aforementioned assessment) in a large room with the speakers way out in the room. Dynamics have never been your systems forte (at least not to these ears) so perhaps Chris's "added hardness" translates to your "lively, dynamic". i.e. a happy synergy. |
I'm the friend Willster mentioned with the bearing wear problem. Not that I would call it a problem myself. All that happened is I noticed the delrin coating on the thrust plate wears through fairly quickly. I thought this might have something to do with the fact that, while my table when new was amazingly dead silent, it didn't seem quite the same a few months later. Mind you, there was still zero audible noise of any kind you could positively associate with the turntable. I'm talking more of a feeling that had been lost or faded away over time. If that was all there was to it then it wouldn't be anything to write home about. But there is a bit more to the story.
The bearing went to a local machinist, who basically said nice work, and offered a few ideas for improvement. The one I decided to try was to replace the brass/delrin thrust plate with silicon carbide, and the stainless ball bearing with silicon nitride.
After many hours of use only the tiniest speck of contact wear can be seen on the new thrust plate. A tiny percentage of the area of wear the stock brass part showed. Amazingly dead silence had returned. This is where Willster got his bearing wear idea.
There is of course a tradeoff in terms of sound. As luck would have it, Chris happened to be in Seattle one day, we were able to hook up, and he spent some hours listening to my system. At some point we talked about the bearing mod. He was surprised, because he did try these materials but felt they added hardness - the surprise being he said there was no trace of hardness in my system. The changes heard in my system (and this is by me, Chris did not have the time to A/B this) were towards a more lively, dynamic presentation.
Anyway, if anyone go the idea that Willsters friend (me) was in any way dissatisfied with Chris or Teres, consider this: the only reason I came across this just now is doing a little research before ordering the new Verus motor. Frankly, having met with Chris on a few occasions, heard platter shootouts and owned some of his stuff, I know from first hand experience it is all good value for money - enough so that I emailed him ordering the Verus BEFORE looking around for more info.
Hope this helps clear things up a little. |
I own the KAB strobe and it is very nice. It is also more accurate than the fluorescent light bulb. The fluorescent light bulb turns on and off approximately 60 or 50 times per second depending on where you live. However, the frequency is never exactly 60Hz or 50Hz, though it is usually close. The KAB strobe, since it runs on batteries and not mains, is more accurate. |
Or, if you want to get fancy, the best strobe/disc I know of is sold by KAB. Worth the reasonable cost, IMO. |
The manual has a link for a down loadable strobe disk. Any florescent light will do the trick. Easy if you have a florescent lights in the room. Otherwise a florescent bulb in a regular lamp will also do. |
My Verus motor arrived a week ago and I have yet to set it up. I didn't realize that I would need a strobe disc and light in order to do the set up. Which strobe disc and light should I order? |
Lew, while browsing one of my father's old EE textbooks from the early 50s, I read that a block of iron placed on top of a transformer improves coupling between the magnetic fields. This is how how a VPI brick is constructed. I don't know about the Skakti stones. |
I think I remember that the Shakti stone does have the property of soaking up some of the stray fields radiated by transformers, over and above the fact that mass loading the tranny helps to reduce vibration. I also think I read that any old out of use transformer, if placed atop a functional transformer, will have some of the same positive effects, but I've never tried that, nor have I used Shakti stones. From the hayday of audiovoodoo, promoted often innocently by HP, the Shakti stone hangs around. I don't dispute that it may do some good, I just am interested in the why of it. |
Lew, yeah - and that reduces the noise below threshold, but I sensed the Shakti added something in addition to plain ol damping - but I'm not a big believer in audiovoodoo until I can do a control and the difference is significant, sustainable and definable. Of course different does not always mean better or preferable, and I think these things have to prove over a period time.
The best application of Shakti stones for me has always been on CDP's (cleaning up digital haze) and power amp transformers/poer supplies, but not so much if the amp has a seperate power supply and umbilical.
Steve |
The Verus arrived here yesterday. Setup was straightforward and operation is simple. Spinup and spindown times are quite reasonable. I do need to retrain myself to not give the platter a push to get things going - caught my hand a couple times just before. :-)
Basically just checked that all was in order and operational. The primary issue for me was the size of the motor controller box and where to put it. The motor pod is sitting on the same 3" maple block as the turntable. Lightly holding the motor as it drives the platter I do feel the traversal of the wheel against the platter as not 100% smooth/continuous. I may need to fiddle with motor position a touch.
Listening at the end of a long evening, I'm gonna recheck my impressions tonight. TT is a Teres 320 which has a 37 pound platter. Ergo, my expectations are more oriented toward improvements coming from an improved motor than from increased rotational stability. Will report back.
Do folks have observations on the sonic character of different Verus torque settings?
Tim
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Did you try a plain old brick or rock or piece of slate as a control for the benefits of the Shakti stone? |
Fred,
The motor continues to deliver the goods. I first had the motor sitting on a detached (from the Micro plinth)solid piece of maple 5" thick on brass footers, but when I switched to the motor sitting on the same plinth as the table the bottom end tightened up with greater slam. This is the current preferred set up. I also got a slightly better sound with a Shakti stone on top of the control box and use a Graniteaudio 555 power cord. A bit of audio voodoo with the Shakti, but it seems to add a bit of bite and clarity - but I need to validate this with extended listening. THe control box needs a small weight on the top to reduce ambient noise from a transformer buzz. I need to have some extended quality listening time this weekend and I full publish a full review. I have some nice pics and I will endeavour to put them up here as well. I have had my IO Sig phono stage out for a tune up at Aesthetix and that goes back in to the mix tomorrow to allow for a true comparison.
Stay tuned
Steve |
Any further listening impressions, Steve?
Inquiring Micro Seiki Techies want to know.
Fred |
This is a very quick initial review on the new Verus motor just received for use on my Micro-Seiki RX5000 - detailed analysis to follow.
The motor is easy to set up, needed some changes via dip switches on the board as outlined in the manual to get the right torque for my heavy platter. Stops and starts with no drama, easy to use, there is an option to stop the platter to change records and with my high inertia platter it takes just a couple of revolutions.
Soundwise, very comparable with my Lenco for PRat, seems to create a solid low end typical of idler drives, coupled with the dynamics of the Micro engineering it takes the deck to a new level over the silk belt drive. It is early days, but very favourable impression so far and I believe I have the best of the Lenco with the extra resonance and depth of the Micro. Best combo so far. More to follow
Steve |
Well, it looks like Harry has jumped on the rim-drive wagon. He seems to be offering the option and down-playing it at the same time. :-O
http://www.audioasylum.com/audio/vinyl/messages/67/677755.html |
We used to make the distinction between ideler or "rim-drive" and direct drive and belt drive. I believe that is still fair. Different solutions for the same problem. |
+++ I think the proponents of belt driven turntables will disagree with this: they will miss the sight of the big external motor with the rotating belt +++
The Verus is external and not direct drive ... |
Hi
The original Goldmund Ref and Rockport Sirius I & II were belt drive.
The Sirius III is DD along with Goldmunds Studio turtables. |
Well, this is not the end of belt driven turntables, but this is certainly the end of the dogma that belt drive is (far) superior to direct drive. I think the proponents of belt driven turntables will disagree with this: they will miss the sight of the big external motor with the rotating belt (wonderful nostalgia, heheh). The Goldmund Reference I tt was a direct drive design. The same with the Rockport Sirius (if I'm right).
Chris |
Tim, The o-ring Chris supplies is from McMaster Carr, part number 9557K228. How about a group power buy?! ;-) Doug |
Chris and all, what is the size and composition of the Verus' O-ring?
I'm already looking forward to lively debates about sonic merit and wear from various O-ring materials (urethane, flourosilicone, polyacylate, etc.).
Anybody wanna buy my tape splicer?
Tim
|
"....could have been torn out of my earliest - and current - writings on the subject....."
Occasionally, some of us forget that johnnantais single-handedly invented the idler table. Fortunately, we can rest assured that he'll always be here to remind us of his place high on top of the Mt. Olympus of Turntables.
|
Pauly,
The flywheel effect of the platter on that cutting lathe would be negligible compared to the 75kg/cm torque generated by the motor. From pictures on the net it's evident that a really decent cutting lathe like the Neumann has a much stronger drivetrain. A lathe strong enough to handle the fundamental drag on the cutting tool should be impervious to small modulations in drag. Still, somehow tools never quite seem to be as good as they should be. I have a metal lathe with a 10" chuck & a 2hp motor & I still manage to find jobs that are too big for it.
I did find a reference to pitch problems introduced by stylus drag on lathes used to cut 78rpm records in the 1920s. |
Hi Ketchup. Agreed. I think it is folly to believe cutting lathes have perfect speed stability. I came across this site where the sell cutting lathes. http://www.vinylrecorder.com/index-e.html. One of the tweaks they offer is a 3.8 kg platter to reduce wow and flutter.
I guess like everything else in life, not all cutting lathes are equal. Some would undoubtedly have less stability that others.
Lewn, my bad I do not mean to be combative. I understand your point BUT nobody can really prove that stylus drag decelerates a platter to soften transients. We accept that as it is based on sound physics and what some folks have heard seem to tie in with that. A cutter slowing down the cutting lathe is based on the same physics. You cannot simply accept the physics for the one and reject the same physics for the other.
Also, I am not saying what I hear is proof that this happens, rather the cutter drag on the cutting lathe goes a long way to explain something I have heard on some of my LP's. I may be totally wrong, but I think physics back this one up.
Regards
Paul |
Lewm,
First, you say that stylus drag might be a good thing. It might, but there is much more to it than stylus drag. My instincts tell me that a cutting head cutting a lacquer puts much more drag on the lathe's platter than a modern stylus does playing vinyl. The trick might be to use a lighter platter than that of the cutting lathe and, along with a stylus, hope that the speed variances are about equal in magnitude and duration.
Second, I would love to hear what some people in the record making industry have to say about speed variances in cutting lathes, but I fear whar I might hear. I think a lot of people into "pro audio" seem to think that we're nuts and that we shouldn't hear any difference between A or B, whatever they might be, or that we couldn't possibly hear something so subtle, whatever it is. How often have you heard that?
Whether my point has any validity or not will take A LOT of very careful experimentation that I bet will NEVER be done, but let's for a second assume that it has no validity what-so-ever and that cutting lathes are rock solid with respect to speed stability. If we assume this, then all the rim drive (Teres), mylar or tape drive (Galibier/Teres) belt drives with massive platter (Maplenoll/Walker) turntable designers are just wasting their time trying to reinvent something that has rock solid speed stability and has been around for years. |
Paul, I think you misunderstood my intent. My main point was that we need someone who is or was in the record-making business to tell us whether Ketchup's point has any validity. And I am only saying that my guess is that it does not, but I admit I don't know. Now you have cited your empirical and subjective experience to contradict me, while also saying that this type of evidence is not acceptable. Your opinion is certainly as valid as mine, but one would need to know more about cutting lathes to settle the matter. |
I think it's important, Jj, but we do already have vacuum platters, reflex clamps, ring clamps, and concave platters to help with warps. |
Just curious. Isn't the common warp in albums causing more variation in pitch than the differences between direct drive and belt drive?
I have a Cardas sweep record with what appears to be an average warp and the pitch variations are very clear as the stylus travels faster over the warp.
Am I wrong that flattening the record should come before worrying about belt versus direct drive in terms of pitch control and prat? |
Lewm, empirical research (i.e. observation) for something as subjective as audio presents a very weak argument. I think Ketchup brought up a very valid point.
If we are to assume that physics tells us a platter will decelerate due to stylus drag, we would be mistaken if we were ignore the fact that the same force acting on the cutting lathe will have the very same effect.
From my own experience I have a few LPs that when listening to I have always thought that the transients were a little bit too quick and sharp to be real. (I am sure everybody on the BB has a few LPs that). I always put that down to the sound engineering tweaking the recording a little, but Ketchups postulation does go some ways to explain the phenomenon. Simply put, it is not inconceivable that the cutting lathes used to create those LPs slowed down more on transients than what my current TT slows down.
Sadly, we do not have any numbers or hard data pertaining to the amount of stylus drag and the effect said stylus drag has on a platter.
Regards
Paul |
Ketchup, One would need to know a lot more about how a cutting lathe works. Perhaps someone among us can enlighten the rest. But if your idea has any validity, then in effect "stylus drag" is a good thing. There seems to be a body of empirical evidence that this is not the case. I would guess that cutting lathes use powerful high torque motors that are securely connected to the lathe, so that heavily modulated passages are treated no differently from those that are less so. But I'm just guessing. |
Ketchup - Your post is most intriguing, and brings up an interesting point.
Are most lathes direct drive? |
It's generally accepted that a constant, steady platter speed will produce the most accurate reproduction. Above, Chris stated that a high mass platter will produce speed variances of low magnitude and long duration, and that light platters will produce speed variances of high magnitude and short duration.
A main goal of TT design is steady platter rotation, but could TT designers be barking up the wrong tree? Shouldn't we consider the speed variances of the cutting lathe and try to produce a TT whose platter mass, motor power, and stylus drag combine to approximate the speed variances of the cutting lathe? If the cutting lathe's platter slows down and recovers due to a heavy modulation, it might not sound right when replayed in your living room if your TT's platter also doesn't slow down and recover at the same rate. Is it possible that rock solid speed stability in TTs is actually a bad thing? |
Very interesting discussion. I look forward to receiving mine in a month or so :-)! |
Pauly, Your stylus drag experiment is interesting...
Physics dictate that the uneven forces from stylus drag will modulate the platters speed. What can be debated is if the effect is large enough to be audible. Our ears are remarkably sensitive to errors in the time domain. Far more so than would seem logical and far more than most would expect.
Contrary to popular thinking platter mass only changes how stylus drag affects speed but cannot eliminate it. A massive platter will reduce the magnitude of the variation but extends it over a longer period of time. A light platter will conversely allow a larger speed variation but it recovers more rapidly. Most, but not all, prefer the shallower variations from a heavy platter but it is a compromise, not a fix.
The Verus motor does show greater improvement (compared to our belt drive) when coupled with a light platter. But there is no evidence that using a heavy platter with a Verus motor is detrimental. We have used the Verus motor with platters up to 70 pounds and as with our belt drive motors have consistently preferred the heavier platters. What we have found is that with the Verus motor platter mass seems to be less important. For example we recently did some comparisons between a 14 pound solid acrylic platter and a 27 pound lead/acrylic platter. With the Verus motor the difference between the platters was about half of the difference heard with a belt drive Signature motor.
So does the Verus motor with a light platter surpass our heaviest platter with a belt? I have not done that comparison but suspect that the answer would be no. But there is much more to the story than mass. The materials used in our 360 platter (brass and cocobolo) sound a lot better than acrylic.
Chris |
I got mine today. Initial comments here:
http://www.audioasylum.com/audio/vinyl/messages/67/675079.html
Bill |
Dgarretson - As Doug points out: "According to emails from Chris, the performance jump vs. belt drive is inversely proportional to the weight of the platter. Lighter platters have less rotational inertia, so they benefit most." Presuming this holds true, in terms of yielding improvement, the lighter platter would to a higher degree - so this may be the more bang for the buck solution. However, in terms of overall sonics there is enough difference between say a 255 and a 320, apart from the drive system, that the latter easily bests the former by a pretty wide margin - at least to my ears. The inertia of the larger platter coupled with superior isolation provided by Stillpoint dampers make significant contributions to speed stability and lower noise. When I upgraded from a 255 to a 320 I definitely expected improvements, but the 320 significantly exceeded my expectations. I would be quite surprised if a 255 with Verus could exceed a 320 with the Reference motor. Over time, I've found my skepticism about Teres improvements consistently disappointed, and Chris' assessments to be quite accurate. Of course I'll wait to hear the Verus and judge for myself, but I have no reason to doubt that it will be an improvement commensurate with the upgrade price. We'll see - I hope the Verus starts shipping soon. Tim |
I hope this is ok to post here. I just found this posting by Mark Kelly over on AA related to this topic.
"The idler drive mechanism has only a few percent of the speed variability inherent in belt drive (due to the lossy transmission eg belt creep).
Most idlers make up for this by using motors which can't hold constant speed against variations in platter drag (like the stylus traversing the record). Anyone who says their stock Garrard holds constant speed simply isn't measuring it properly.
As against this, the short term speed stability of an idler is excellent due to the almost lossless transmission from a motor with a high amount of flywheel effect. Most people assume this is due to the motor having lots of torque but that's not the case.
The other problem is noise - an idler definitely transmits more noise than a belt and they can create extra noise all of their own if the bearings aren't perfect.
Altogether its a toss-up.
Mark Kelly" |
Me, too. :) But I'd also like to hear that from others as well. |
"A given motor speed and torque in the rim drive system may have a range of platter weight that works best with that given motor. Then again, it could be testament to how well these heavier platters with mylar belts actually work."
I'd like to hear an opinion from Teres on whether the Verus with a light Teres platter surpasses their heaviest platter with mylar tape drive. |
Dgarretson,
That is along the lines of the point I was attempting to make. A given motor speed and torque in the rim drive system may have a range of platter weight that works best with that given motor. Then again, it could be testament to how well these heavier platters with mylar belts actually work. ;)
I think the extra gears of a reduction system are going to introduce more noise. IME, gears don't mesh silently and there will still be slop between the teeth. That is why the Lenco rubber-tired idler wheel can work well when everything is in good shape.
"Finally, issues of force and compliance surrounding stylus drag can't be too much different than issues regarding VTF. This is handled easily in a TT arm by counterweights & gravity."
I would agree with you on how easily this is handled except that so many tables/arms don't. Perhaps that attributes to the rising price structure of many 'table/arm lines? |
Dan_ed,
Somewhere in this thread it's reported that in testing, Verus rim drive produced the greatest improvement in combination with the lightest Teres platter. It would seem that with rim drive (as with idler drive), high platter mass might actually impede speed stability (probably at the point where the motor has insufficient torque to meet the higher rotational force associated a high-mass platter.) But I suppose that high-mass platters are also better at resonance control. So there is likely a trade-off with how light one would want to go without resorting to fancy TT mats and other approaches to resonance control.
Since with rim drive as with idler-drive, speed stability is entirely determined by the motor, it would be interesting to know whether the 1800 RPM motor of the Lenco offers an inherent advantage. I assume that with the Verus, the drive pulley is pressed onto the spindle of a low speed motor. Perhaps the best rim-drive design would be a high-speed motor with multiple wheels and a step-down transmission. This might also improve isolation of motor noise.
Finally, issues of force and compliance surrounding stylus drag can't be too much different than issues regarding VTF. This is handled easily in a TT arm by counterweights & gravity.
|
Stylus drag real or myth?
Some time ago I did an experiment to determine just what effect stylus drag would have on an LP. I used a DL103 set to 2.5 gram tracking weight and used a regular 120 gram LP on a cheap mat felt mat (I believe off one of my old Regas). I made a small notch in the edge of the record and aligned it to a piece of tape on the platter. Looking up the edge of the tape (akin to looking down the sights of rifle) I could line up the notch in the LP very precisely.
The one side of the record was played (approx 20 min). The record was unclamped.
Now if the average groove speed is about 14.1 inch per second (20 inch per second on the outer grooves, 8.3 on the inner most groove), that means I am looking at about 1410 feet (16920 inches) of groove length.
After playing, the record shifted at the very most, not more than 1/64 of an inch. That means that over a period of 20 minutes and distance of 16920 inches, stylus drag amounted to only 1/64 of an inch of record slippage; or stated differently 9.235e-5 % slippage.
I did not bother to measure/calculate and compare the amount of drag needed to slide the unclamped LP on the felt mat vs. the drag need to overcome the rotational inertia of a 12 pound platter (never mind the 30 plus lbs Teres platters). I simply cannot buy into the idea that the force of the rotational mass of a platter would be less than the force required to make a 120gram LP slip.
I have not heard a Teres as yet, but I did own an idler wheel (TD124). The idler wheel had no more speed stability than any of my AC motored belt drive turntables.
Regards
Paul |
Don't forget there is also the benefit of high platter mass to counteract the negative acceleration. It is the weight of that spinning flywheel that stores energy and helps get the car off the line. Too heavy, the car is slower to build rpms. Too light, and the car doesn't leave as quickly. The whole system should be analyzed, not just the individual parts. Relative to those light-weight cast or stamped metal tables of the earlier idler/rim drive 'tables the Teres platters are 3 or four times the weight. As Swampwalker said, the high torque may be great for getting the platter spinning from stop but once the platter is at speed, how much torque is needed to maintain constant speed? Which is a state of near zero acceleration. The energy stored in a 30 to 40 lbs platter is helping a lot. The connection of the LP to the platter must also be considered. It does no good if the platter is marching along but the LP is slipping on the surface.
"by offering relative immunity to minute changes in platter speed that might other wise result from stylus drag"
I would agree with that. IMO, this is also why the mylar belts are superior to all other belts I've heard. They don't stretch at all. However, they can slip ever so slightly and that is where the door is open for the possibility of rim drive. Obviously, the next step up should be direct drive, and it goes without saying that every drive systems needs to be well implemented. |
Jean,
I think I understand your comparison of idler drive to belt drive, but I'm lost in your comparison of idler to Verus rim drive.
I would think the comparison of rim drive to idler drive boils down to the relative compliance of the interface between motor and platter. With rim drive there will be speed instability if the rubber ring around the transmission wheel has excessive compliance. Is idler drive really much better in this regard?
There is also the matter of transmission of motor rumble. But as with your replinthed Lenco, noise problem can sometimes be engineered.
The torque necessary to meet the changing force of stylus drag is far less than what is necessary to lift an 80 lb. plinth. But it is nice to know that a Lenco motor could be used to drive an electric bicycle. |
Swampwalker, I don't want to wade into an argument about belt drive vs idler drive vs etc, but "torque" is defined as angular force. So, torque is the product of mass multiplied by acceleration, like any other force. Then, if stylus drag could be thought of as the equivalent of a force that delivers "negative acceleration" to the platter, a high torque motor might be of benefit in overcoming it. The question you raise is however a good one which I have not seen addressed; just what in fact is the magnitude of the force we describe as "stylus drag"? I dunno myself. I think it's key that stylus drag is constantly varying during different musical passages. That's where idlers may have a real advantage, by offering relative immunity to minute changes in platter speed that might other wise result from stylus drag. |
Well, John- who would have thought that that humility would be your most endearing character trait? ;~) I'm not a mechanical engineer or a physicist, but wouldn't torque mostly be an issue in terms of coming to speed from a stop? Once turning at relatively constant 33 or 45 or 78 rpms, wouldn't there be very little torque necessary to overcome stylus drag. I ask this as a serious question, based on my perception of torque as an attribute of a motor that contributes to its ability to accelerate from a stop or at least from low rpms, as in a drag racer from a starting line, where torque at low rpms is just as important as total horsepower at high rpms. |
Gee, the opening statement in the advertisement for this new take on the idler wheel/rim-drive could have been torn out of my earliest - and current - writings on the subject...except for the inclusion of idler-wheel drive as a victim of speed instabilities. Ironic, in a way, since it is the controversy I started a few years back about the speed instabilities of belt-drives - which Teres built their name on - which started the whole debate about which system was superior, sorry if this is boring you, Viridian, I realize that belt-drivers are feeling severely put-upon these days.
Long ago and still now, the bedrock of my insistence the idler-wheel system was superior to the other two systems (DD and BD) was based in simple and actual verification, simple (the lesson in science I kept/keep talking about): comparison in the system of your choice. A theory stands or falls by the experiment, which either proves or disproves it. If experiment/comparison/verification proves a theory wrong (i.e. that belt-drives are not adequate to combating the VERY important and nefarious Stylus Force Drag, which idlers were actually and specifically designed to combat), then it is time to abandon theory. Apparently, by the release of this variant on the rim-drive, Teres now admits I was right, implicitly.
But is this new system superior to the venerable idler-wheel system in terms of speed stability, as advertised, which I have insisted from day one was THE Prime consideration in designing turntables (and only idler-wheel drives designed to provide adequately)? Only verification/experiment/comparison will tell. As with the growing list of megabuck belt-drives falling before the Lenco and other fine and properly set up idler-wheel drives in front of witnesses, this new Teres system will have to face the music, and eventually be compared to a properly set-up idler-wheel drive.
The Teres system is designed in such a way that the motor CANNOT provide the torque of idler-wheel drives, which with their massive 1800 rpm motors can actually lift an 80-pound plinth when engaged at high speed (i.e. 78 rpm), since such a powerful motor directly applied would guarantee rumble (which is non-existent in a properly rebuilt idler-wheel drive, due to its separate and spring-loaded wheel). Not only is it about SPEED STABILITY, it is also about TORQUE.
That said, it is music to my eyes/ears to see the speed stability of belt-drives questioned in a advertisement of a spin-off of the rim-drive technology (sorry again if this is boring you Viridian ;-), and to Teres I say Bravo. I also wish you luck in the coming comparison :-). |
"No springs, pivots or hinges, just gravity."
Sometimes the old ways are still best.
Thanks for the info Chris. |
Jeff, I don't know what the force is on the o-ring but it's more than a gram.
We use a very simple but effective method to keep even pressure on the o-ring. The motor pod simply leans against the platter. There are two small rubber feet under the motor pod that are offset from the center that causes that pod to tilt. The pod stands straight up and rests on three points, the two feet and the o-ring. really easy to setup. No springs, pivots or hinges, just gravity.
Chris |
Just curious. How much force does the o-ring apply laterally against the platter? 1/10 gram? 1 gram? Other?
What keeps the o-ring from moving away from the platter over time? The weight of the motor? Other?
As the o-ring wears due to friction, would the user need to move it closer or otherwise adjust its distance to the platter? Or does it matter so long as the o-ring is in contact with the platter?
Thanks for considering the question. Jeff |
