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Please help me trouble-shoot an issue with my setup.
My system: VPI Classic II, Classic arm, Lyra Skala cart (recently refurbished with a new cantilever and stylus by Soundsmith).
I recently filled the tonearm pivot cup with the VPI damping oil in an effort to tame some high frequency breakup I was hearing. I think this tweak was a success. I had never used the oil in 6 years of owning VPI tables, but I think it makes a difference.
Soon after this event, I noticed that, when placed in the groove of a spinning record, the cantilever immediately settles at an angle to the cart body. If you think of the stylus tip as a pivot, the cantilever points inward towards the center of the record, no longer parallel with the cart, nor with the record groove (as far as I can tell). The angle is so severe that I can see it with the naked eye, and can see that the cantilever shaft settles in against the (right) side of the hole in the cart where the cantilever enters. It's fairly dramatic.
OK, I thought. I'll check out my cart alignment. I then spent 3 hours checking and rechecking my alignment on three protractors (VPI, Mint, DB). The alignment looks correct, and if I lower the stylus onto one of the protractors or onto a non-moving record, I do not see the cantilever angling away from straight.
So, then I think it must be anti-skate. Maybe the skating force is pulling the cartridge towards the center of the record and pulling the cantilever at an angle. I had never before used VPI's mechanical anti-skate. It took me a bit of tweaking to get it working, but I've now got it so that I can pretty easily adjust it for more or less anti-skate force. First, I adjust it so that the stylus slowly travels towards the center of the record at a record's lead out grooves. (This is what Soundsmith recommends.) With this amount of anti-skate applied, at the end of the record the cantilever sits correctly in the groove (straight and parallel). But if I drop the needle in at the first 1/3 or the side, the cantilever and cart body are not straight; the angle is still there. If I adjust the anti-skate force to counteract the angling at the first 1/3 of the side, then the end of the record has entirely too much force, and the needle will skip out of the groove and travel towards the outside of the record.
What's going on here? Does the VPI anti-skate vary from the beginning of a side to the end? Does the natural "skating" force vary from beginning to end? Is it possible that my Skala's suspension is damaged and thus particularly sensitive to skating and anti-skating forces? Might my problems be related to the use of the damping oil? (I have not tried removing it.)
Any ideas would be very much appreciated. Thanks for reading all the way to the end of this...
Jeffrey
Brooklyn, NY
Follow Ups:
Regards, JCB2005: Isaac Newton describes centripetal force as "That by which bodies are drawn or impelled, or in any way tend, towards a point as to a centre." This is not a constant. On a horizontal plane, frictional coefficients and offset, as well as distance from the center of rotation affect this force. Centrifugal force is the opposite. This is the force that, acting against gravity, maintains a satellite in orbit.
Stylus overhang is a factor. This might be illustrated by drawing a straight line from the position of the stylus at, in this case (we're not talking about alignment here), the two most usable points, those being the first groove and the last (another moving target). Now visualize the arc transversed by the stylus at the end of a pivoted arm, it should intersect the previously drawn straight line at only the two points terminating the straight line, something like this: I). Where the point of maximum departure from the straight line actually develops depends on the interdependent influences of tonearm length and overhang (effective length). If one thinks about it, it might be seen that these forces reverse when the stylus traverses the center of the arc, visualizing that it isn't necessarily in the middle of the distance traveled, somewhat like rolling a marble across a tilted bowl.
A ballista is an ancient weapon powered by twisted strands using two levers with torsion springs instead of a prod, the springs consisting of several strands of twisted rope (Wikipedia). From your description and photos, it appears there is too much of this torsion (anti skating) applied and it seems to be relaxing (unwinding) as the stylus approaches the inside grooves. It looks like you've wound your tensioning/anti skating adjustments in the wrong direction, whatever it is you've done you might try the reverse application.
Peace.
In general, if there are any issues with a Soundsmith rebuilt or new cartridge, we are here to help. There is some major misinformation in some of the below posts, but hopefully this will help.Skating force is NOT caused by centripetal force. It is caused by the fact that the cartridge is mounted at an angle with respect to the arm tube (please note that most arms have the head shell at an angle). This is done to allow best OVERHANG position in terms of ZENITH (rotation of the cartridge clockwise as viewed from the top). This alignment (there are several - which have different advantages) allows "best" compromise for a pivoting or radial tracking arm. BUT - it creates skating force. Why??
Imagine a gate when you pull on the free end of the gate. The force pulls on the hinges, and the gate assumes a straight line between you and the hinge. NOW, imagine a huge, curved gate, curving to the left, with the hinges on the far end. If you pull on the free end of the gate, as if the hinge is straight ahead of you, (which it is not - it is off to the far left of you) - The gate will swing LEFT - this is because the force wants to line up in the direction you are pulling - it wants to line up with the hinge. The gate will therefore swing left until you are pulling directly at the hinge. Same with a tone arm. The "stiction" of the stylus in the groove pulls the tone arm; and at varying amounts to complicate matters! Lots of loud passages?? More groove modulation, MORE STICTION. Center of the record?? Groove modulations are TWICE as close together for the same frequencies (as half the vinyl is flying by), so MORE STICTION.
So - More skating force both when loud passages come, and more at the end of the record. So....antiskating is needed. How much?? Good question. Since stiction and the resultant skating forces are a moving target, there is no “perfect” amount of instantaneous Antiskating force that can be applied....HOWEVER....Frank Schroeder came up with a method AND AMOUNT of Anti-skating to use that does NOT require instrumentation OR a test record, and I could not agree more with this method. It DOES fly in the face of test records, but most everyone I have suggested it to has agreed that the sound is better. But it also serves to equalize record and stylus WEAR on each groove wall as well. We suggest LESS force than test records suggest. Why?? Because music spends MOST of its time at about 30-40% modulation levels. So why would one adjust anti-skating for only MAXIMUM recording levels?? That would mean that 80-90% there would be uneven force on the groove walls as a result of too much anti-skating force. Better to be correct MOST of the time. How do you do this??
Frank suggests that at the end of the record, you place the stylus on the TOP of the surface, where it will rest for a moment before popping into the run-out or end groove. Adjust the Anti-skating so the stylus stays put, OR drifts slowly in (Franks preference).
With the VPI, this is hard – but Soundsmith is producing a new antiskating device soon (called Vivenda) whose adjustment follows the tone arm and has no string – (thus allowing the arm to be removed quickly, and multiple arms to be used easily as the setting follows EACH ARM).
But how to set the VPI’s in the meantime?? VPI’s suggestion to twist the wire is too gross (in my opinion) and the use of the VPI antiskating device is a great solution - if you have one. Here is what we have suggested with our Soundsmith alignment guide Version 4.11
Which includes the following on how to set it with the VPI device, or with our Vivenda:
*****************ANTI-SKATING AND VPI IMPORTANT ISSUES:
Some of us who own VPI tables are aware that in the past, VPI’s suggestion was to twist the signal cable one way or the other to affect a proper antiskating force. I have found that this is a fairly gross method, which does not allow for fine adjustment. VPI is now providing an anti-skating device, however, our new Vivenda Soundsmith Anti-skating device allows far easier adjustment, as well as allowing the arm to once again be easily removed, a feature that is well worth having. The other advantage is that the adjustment for antiskating now FOLLOWS the tone arm, so that multiple arms can again be easily used without having to adjust the antiskating for each arm each time. With the VPI supplied string type antiskating device, one must appreciate that its use does take some time to get right, as one is working against not only the skating force for the cartridge itself, but the side force from the stiffness of the signal cable as well. I have had some luck using the VPI anti-skating device by adding small brass washers (if needed), sometimes between 3 and 5 of them, to the far small arm that does not have the nylon string attached. I positioned them between the rubber o-rings that they supply to hold them in place and at the proper height – and it allowed me to adjust the force to exactly what was needed. Patience is often required.
The way to start with the VPI arms with EITHER anti-skating device is to FIRST INSTALL either type of device, but if using the string type VPI device - DO NOT HOOK UP THE NYLON WIRE FROM THE ARM TO THE ANTISKATING DEVICE. Then, PLUG IN the tone arm wire WITHOUT twisting it. If the tone arm skates INWARDS as described above in the antiskating directions, then you are OK. If it moves OUTWARDS, you must unplug and twist the ARM CABLE WIRE, (PLUG IT BACK IN EACH TIME) till the stylus tracks INWARDS AT ANY SPEED on the RECORD surface near the end lead out groove.
What you may find in fact is that with the signal cable twisted one way, the stylus skates outwardly FAST, and with one more twist, now skates inwardly fast. THAT is your (gross) setting point. You want to find the point where the twisting JUST gets the arm to skate inward.
THEN – HOOK UP THE ANTISKATING NYLON WIRE (or adjust the Vivenda Soundsmith device) AND add JUST enough Anti-skating to slow it down to the desired rate as described above. Using one or more washers (if needed) on the far arm of the anti-skating device will ADD antiskating (and slow down the arms inward speed) as will hooking the nylon wire in different positions up on the other arm. PATIENCE…….PATIENCE…..
Peter Ledermann/Soundsmith
Edits: 01/21/12 01/21/12 01/21/12 01/21/12
This regards your Zephyr (which I love) on my JMW 10.5i, which has the Nordost wiring and VPI AS fixture. I'm running the Zephyr at 1.4g per the last time you and I spoke.
Using the twisted wire method ONLY, my arm is set to drift ever-so-slightly back to the armrest (I find that a ball of Mortite stuck temporarily at the end of the armtube helps it float freely). When set with the stylus on top of the surface at the end grooves as you suggest, it always stays put without moving inward or outward.
As noted, this is without using the AS fixture at all. My question: Under these circumstances, Is there any real reason to use it?
Peter, You know more about this stuff than I ever will, but I do know a little about the JMW arm having used one for a few years. The wire twisting thing gets way over blown. I agree if you twist the wire either way one revolution, it is too much. However, if you plug in the wire with absolutely no twist with the arm in the rest, the spring action is now almost perfect in that as the arm rotates toward the spindle, the spring (wire) is tightened and this applies a small amount of force outward in the right direction. I am sure that some will see this as imperfect as the force gets greater closer to the spindle and is decreased toward the outside of the record, but it works out to be a very small amount of anti-skate being applied, and as you said, skating varies and less is more.
As I mentioned earlier, you can test this small amount of torque by unweighting the arm until it floats level above the record surface. Holding the stylus over the innermost grooves, carefully let the arm go. It will float toward the outer perimeter of the record. You want it to float gently rather that furiously.
As far as twisting the wire, this is too often done grossly. The way to "twist" the wire is to hold it straight up and gently twist or untwist the wire. Plug it back in straight and with a nice arc - no curly Qs. I didn't discover or make this stuff up. It is somewhere in the archives described by HW. I read it years ago. He doesn't post around here anymore unfortunately.
If what I have described is not precise enough for some folks, it is an excellent starting point to adjust from with your or VPIs add on devices.
I agree that SOMETIMES, the UNTWISTED, unmolested leadout wire if plugged in without change, happens to be close to what one needs. Since I have used, taken to shows, sell Soundsmith carts with VPI tables (I am a dealer)and love VPI tables for certain reasons, Ihave experienced both good skating adjustments with the cable plugged in normally, and also seen bad skating force with the cable plugged in normally. I also beleive it changes or relaxes with time, so a good thing to check periodically via Frank's method.
Unfortuantely, the method of testing antiskating amount with the arm floating in the air- NO VTF, does NOT take into account the varying amount of stiction resulting from varied amounts of applied VTF for varied models of cartrdiges, so it is almost irrellevant! it MIGHT be a good starting piont....but..... There is a large diference in required skating balanced forces with a cart tracking at 1.2 grams, than one at 2.5 grams, which is preciesely why you need to test the amount of Antiskating ON THE RECORD as per Frank's suggested method. Yes?? No???
Peter Ledermann/Soundsmith
It doesn't sound to me like you have what people normally refer to as a bent cantilever. I think that you are saying that it is straight until you set the stylus in the groove.
Anti-skating with a JMW arm should be set so that when the arm is unweighted (floating) and released at the innermost grooves, the arm should swing outward toward the outer edge of the record. That means that if it were set too aggressively, the cantilever would appear to deflect opposite from the way you describe. Checking this would rule out excessive lateral forces. Just keep in mind that air currents can rotate the arm when unweighted. There is very little friction in the unipivot bearing.
You say that the cartridge was recently serviced by Soundsmith. I would contact them. From what you describe, the suspension seems to be weak laterally. We usually think of a cartridge suspension that is weak kind of dragging. I am not cartridge repairman, but I would suspect something might be wrong with your cartridge.
Good luck.
It sure looks like your stylus is bent and twisted. Send it out for repair.
All the posters suggestions may be helpful but, pics suggest your cart simply has a bent cantilever. IMO, time to nut up and get the visa card ready.
...the stylus seems to exit the cartridge straight on photo 2, before contacting the record. But in photo 4 (record playing), the stylus is angled sharply towards the outer edge of the record.
Now I see why you are thinking it is an anti-skate issue. That's what I would have thought.
However, I am also wondering about the condition of your arm's bearings, and other issues such as cable drag that would tend to restrain the arm from moving freely with the needle as the grooves guide it along. Your arm should not resist, even slightly, rotational motion along the path of the grooves. See if you can feel any resistance.
Thanks all for the posts. I took some photos with my low end camera. I'm beginning to see an angle in the cantilever as it exits the cartridge body. But I also think this angle becomes more acute when the stylus is pulled by a moving groove.
All photos were taken with the anti-skate disengaged.
[Is it possible to post more than one photo in a message?]
PHOTO 4/4: RECORD SPINNING
The azimuth looks off in this picture as the cartridge and its reflection are not parallel. This shouldn't be enough to cause such a severe deflection but I would try to correct this first.
Anti-skating force could only help in this situation.
It sure is...
After you 'choose file', just select 'preview message' instead of 'post message'. You can then use 'choose file' again to select another image. You can perform this over and over again. Keep in mind that the last picture you select will appear at the top of your post and the first at the bottom.
Of course once all the images are in the post you can select them and move them around as you wish before posting the message.
I hope this isn't too confusing...I'm not much good for 'splaining tech stuff.
Waxxy
Thanks all for the posts. I took some photos with my low end camera. I'm beginning to see an angle in the cantilever as it exits the cartridge body. But I also think this angle becomes more acute when the stylus is pulled by a moving groove.
All photos were taken with the anti-skate disengaged.
[Is it possible to post more than one photo in a message?]
PHOTO 3/4: RECORD STILL
Thanks all for the posts. I took some photos with my low end camera. I'm beginning to see an angle in the cantilever as it exits the cartridge body. But I also think this angle becomes more acute when the stylus is pulled by a moving groove.
All photos were taken with the anti-skate disengaged.
[Is it possible to post more than one photo in a message?]
PHOTO 2/4: CUE UP
Thanks all for the posts. I took some photos with my low end camera. I'm beginning to see an angle in the cantilever as it exits the cartridge body. But I also think this angle becomes more acute when the stylus is pulled by a moving groove.
All photos were taken with the anti-skate disengaged.
[Is it possible to post more than one photo in a message?]
PHOTO 1/4: SKALA CARTRIDGE ON MINT PROTRACTOR
> Does the natural "skating" force vary from beginning to end? <
You bet. To experience it yourself, find a playground merry-go-round as pictured and climb aboard. Have someone spin it while you are at the center. Keeping the same rpm, slowly move outward toward the edge. You'll feel the effort to remain on the platform increase as you move outward (centripetal force). This is what the anti-skate adjustment works against to offset.
I set my anti-skate to be neutral about 1/2 way across the playing surface because one setting won't apply to both the outside and inside areas.
I wonder if your new stylus is damaged in such a way that it digs into the groove with excessive friction that in turn causes excessive skating force. I would recommend checking your stylus under a microscope to make sure it isn't broken or damaged. The problem might also be the result of a weakened suspension, but if that were the case, I would think the cartridge body would be dragging on the LP as in a collapsed suspension.
I believe that antiskating is very important and should be adjusted properly, but I don't think your arm and cartridge should behave as you describe even without using antiskating.
I hope you find the problem and, more importantly, the solution.
Best regards,
John Elison
Jeff....I doubt its an anti-skate issue. Regarding damping...you should need very little if any. Too much damping will ruin the sound. Use damping for sound improvement..not tracking problems. Put only very little in the cup and listen for the sound to be better. If it is add another drop. There will come a time when the sound will be dull and flat..use a Q-tip to remove some of the fluid. ...to answer your skating question...yes...skating will vary from the beginning to the end of the record. This is adjustable with the VPI anti-skate device. If you see you need more anti-skate at the beginning of the record, you can turn the a/s device so that it is horizontal at the beginning of the record, and as the record is played, the device either lifts or lowers which lessens the force applied as it traverses the record. I still think this is not the problem however.
;)
Never attribute to malice that which can be adequately explained by stupidity.
.
nt
You wrote, "Most good arms don't have any provision for it..."
Please cite some examples of "good" tonearms that have no provision for anti-skate, lots of them, to support that statement. It might be more accurate to say, "A few good tonearms don't have any provision for it."
You are entitled to your opinion about using the anti-skate devices built into and onto most tonearms, but whether you like it or not there is a skating force generated when using a pivoted tonearm. I know it is trendy to ignore that fact of life. When i have tried ignoring it, I have always found that I prefer the sound with at least a minimum amount of anti-skate force applied.
Hardly, and the need is lessened with longer 'arms.
Never attribute to malice that which can be adequately explained by stupidity.
I am waiting for a convincingly long list of "good tonearms" that have no anti-skate mechanism.
Did you read my post? I wrote that it was "trendy" to do without anti-skate, in agreement with your preference. How long did you plan to make your tonearm? At 12 inches, skating force is still an issue.
Also, compile your own list from your own online research.
I use two excellent tonearms without anti-skating provisions. They are some of the best I've heard.
Never attribute to malice that which can be adequately explained by stupidity.
nt
.
Have Fun and Enjoy the Music
"Still Working the Problem"
Jeff, One possibilityis that one of the two mounting locations on the cartridge needs to be shimmed so that the axis of the cartridge body is perpendicular to the headshell. My V15 came with shims to do this, and in fact the cartridge does need a shim to be trued up.
I would also say that extreme misalignment as you have described suggests a misaligned shaft.
Any chance you could take a photo showing the cartridge, headshell, and stylus in frontal view while a record is playing?
Edits: 01/20/12
"Does the natural "skating" force vary from beginning to end?"
Yes, but I don't think this is your problem.
There's something else happening but I don't know what.
I would have the suspension of the cartridge checked.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
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