Strange Tonearm Tweak. Long


As you all know, I am a little different. I like to read and study stuff like tonearm technology. I noticed that some of the better unipivot designs have employed "outrigger" style outboard weighting systems on their arms, that work like a tightrope-walker's balance pole. This not only balances azimuth, but also gives the arm better stability to lateral deflections from the cartridge suspension, so the arm is not moved when the stylus is pushed laterally by the groove information. I began to think on this, and I wondered why no gimbal-bearing arm makers are doing this. Surely since the vertical plane rides on a vertical axis bearing, there is still some chance for the arm to be laterally deflected by the stylus, when the stylus should be doing all of the moving, not the arm. I think that this is why they use heavy arms, but a heavy arm in the vertical movement plane is not good for tracking. A heavy arm in the horizontal movement plane is good for resisting sideways deflection that would impair pickup function.

So I decided to try increasing the mass of my tonearm in the lateral plane, while keeping it light in the vertical plane, by the use of "outrigger" weights, just like a unipivot does.

I bought lead fishing weights that looked like long rifle bullets(just the lead part) They were about an inch long and about 3/8" diameter, and weighed 12 grams each. I drilled into the bases about 1/4" and press-fitted them onto the nuts that hold the arm into the bearing yoke, so they stuck out straight sideways, like sideways spikes. This put the weight out pretty far to the sides as outriggers, and kept the weight centered exactly around the bearing pivot axis so it did not increase the vertical mass significantly, but it did very slightly. It did not influence the tracking force at all.

So now the arm had outrigger stabilizers on it in the horizontal plane of motion.

I put on a record and sat down to listen. Let me tell you, fellas, this was a mind blower. I have never heard this much information come out of a cartridge before. I heard sounds on records that I had listened to for 30 years, and never knew those sounds were on the record! And I have had some pretty good analog gear in my time. And what I didn't own, I heard at the audio store I worked at. This is the most astounding mod I have ever heard on a tonearm. And it cost me $1.49 for the fishing weights, and I got 3 extras.

The only slightly negative thing about it, is that it increases the anti-skating force, so you have to cut that back a little, and if you have some marginal scratches that might skip, they are more likely to skip with this mod, due to the resistance to sideways movement provided by the outriggers. I had this happen once last night, but I didn't consider it a problem.

But the increase in dynamics, and detail and overall sound quality is astronomical. It blew me away.

I have a DL103, which is a very stiff cartridge, and it may be that this is not needed for a higher compliance cart. But, I think that it would be good for anything that is medium or lower in compliance.

The key to it, is that it only increases the resistance to sideways movement, without interfering with the effective mass of the arm, or the vertical swing movement that needs to stay light to track warps. I played some warped records with this mod, and they played just as well as without the mod, except they sounded better.

I have a pretty good analog setup now, but I can say without reservation, that this mod made my rig sound better than any analog rig that I have ever heard in my life. I have never heard a Rockport.

Stabilizing the arm against unwanted lateral deflection increases the information retrieval and dynamics by a very large percentage. If your arm is not set up like a Rega style arm, then you can glue a 1 ounce long rod across the top of the bearing housing(sideways) like a tightrope-walker's balance pole. Use lead if you can, it won't ring. You don't have to do any permanent changes to your arm that might wreck its resale value to try this out. If it has anywhere near the effect on your system as it had on mine, you won't be taking it off.

It may come close to the movement of your cueing lever, so make sure you have clearance to use it. Mine was close, and I have to come in from the side now to use the lever, at the end of a record. That is fine with me! This was a major, major improvement in the sound of my rig. It is staying permanently. As in "forever".

If you are a little tweak-oriented, and not afraid to do stuff like this. You should try it. It will knock you over.
twl
Very well broken down, Twl. I agree about the fundamental aims you suggest. Your analysis of the probable dynamic response limitation of a fluid damper reinforces the reasoning behind Mr. Townsend's implementation I was expounding on above.

But I must point out a flaw, or at least a simplification, in your characterization of mass-damping as a "static" system. Assuming negligable bearing friction (and this might not always necessarily be the case, but for now I will assume that a premium bearing's friction will fall below the level where it would play a larger role in dynamics), the horizontal mass of the tonearm does not entirely resist the arm's deflection by the cantilever, as you state, but conforms to the basic principle 'for every action, there is an equal and opposite reaction'. In other words, the motion of the stylus will produce deflection in the cartridge/tonearm which is inversely proportional increasing mass of the cart/arm (and also to increasing cart compliance), but this delfection will not = zero, just as in the fluid-damped example. (Had it = zero, you then would have been implying that there existed some 'mass threshold' for deflection, which your unmodified arm hadn't yet crossed, but that had been crossed once you added the extra mass. Of course, and again assuming bearing friction isn't mucking the system up at this point, this isn't the case; there is no 'mass threshold' - it is a continuum, and you have simply moved down the scale in the direction of less deflection.)

What the levels of allowed deflection would actually be in each example of these respective damping systems is unknown to me, and I would guess is likely to remain so. Obviously, in each case there are many variables to be played with that would affect the answer. To achieve an optimum balance of dynamical attributes for any given cart/arm combination, the fluid system allows for relatively easy adjustment via modification of the fluid level, so the mass-damped system should probably feature a method whereby the user can either change the amount of applied mass, or more likely adjust its distance from the pivot point, like a common counterweight adjuster, either by sliding or helical means. (Twl, did I just suggest a major price increase? :-)
The effect of the cantilever deflection in the reverse is a real thing. I've read about it and observed it. When you get your fluid damping devise (where are you getting it, by the way, so we may obtain our own), you may be able to observe it as well. I am blessed with near sightedness, and if I may pause to brag, I can count the seven strands or litz wire in cardas. To make it easier to observe, I get my mag-light and look head on at the cantilever, observing its revative movement with the cartridge. Then also I sometimes find a spot in the background and observe both the movement of the cartridge and the cantilever as it traverses the record. It is much easier to see with a record that is more off-center than usual, but it is rare that I find a record that I can't observe as being off-center. I have, and do, observe less movement of the cantilever when I damp the arm.
I'm going to jump around- first, yes the last sentence is speculation, I'll explain why later,
I am seeing two separete reasons/uses for damping fluid.
The one reason, is the centering of the cantilever in the coils. The other is the taming of unwanted frequencies.
On the first point on fluid, I am suggesting that the cartridge is a more accurate transducer with its cantilever centered in the coils.
On the second, There is both the issue of the speed at which the cantilever moves (which translates to unwanted bass information, the movement of the cantilever transmitting a bass frequency, which is the 'bell curve' stated above) and the control of the other frequencies higher in the audioband, the resonences.
Now I bounce again. You are correct in your statement of the tonearm being of mass according to the complience, as one reason tonearms are heavier than they used to be, and mass having other purposes. The current thinking in design is to keep the moment of inertia as low as possible in all planes, and at the same time, add as much mass as possible while keeping the moment of inertia low. Tonearm makers are also adding mass at their bases (no doubt allowable by better tables). This can be likened to the effects of a heavy platter being a better sink for resonences, as opposed to just better speed control. Or a heavy suspensionless table as opposed to one that seeks only to isolate.
The other trend, although not new, is the use of new lightweight materiels. The reason for this is not simply to make the arm lighter, but to make the arm stiffer by using more of these stiffer materiels. The stiffer the arm is, the more energy is channeled to these massive energy aborbing bases, and the more solid the headshell is at the cartridge as a result of all this.
Now I bounce back to the meat of our discussion. If we explore the use of damping for the second reasons I stated above, and we explore what is happening at the cantilever as far as movement (I like the bell curve analogy) we may be able to get better results by substituting mass for the reasons we use fluid in that area. The evidence I use to support this is that 1) arms have been getting a lot heavier, and that they seem to be attempting to put it where the moment of inertia would be lowest, 2) The graham arm has its weights slung out at an angle for stability and proper tracking of the cartridge offset angle, and may be enjoying the effects of greater horizontal mass as a side effect, 3) the reputation of linear trackers to have good soundstaging qualities, as they have a disproportionate horizontal mass to their vertical mass, perhaps an overlooked side effect in their quest for accurate transcription.
All of these arms use fluid, however, and in the case on the linear trackers, before it was made available on the E.T., the heavier armtube had a reputation for snapping cantilevers, for the first reason I stated above for the use of fluid. The wheaton also uses fluid, (a real heavywieght), slung out in what seems effective for tracking more than transferring resonences, and of coarse the immedia and graham both depend on it for proper operation.
Further evidence I suggest, and this is perhaps the most compelling, is that the rb-type arms are the lightest in this class, and that they have all benifitted from adding more weight from aftermarket counterweights, And in the deliberate attempt to add weight only in the horizontal plane, seems to have shown results disproportionate to simply adding more weight, and was added in what was stated in the beginning of the thread as perhaps an oversight to why the graham works so well. (the rega does not need counterwights for lateral stability the way the graham does).
I would correlate that fluid on a rega is a rarity and that it is also a lightweight.
So my thoughts now are, do we need to emply fluid on the rega to explore this to a higher limit, and also, if we choose to use more mass, if we would be better off not using fluid for certain applications. There may be trade offs as to how much we allow the cantilever to move in relation to the cartridge, wheather or not the cartridge/arm would work better being in a static position over the record, and reap the benifits of stability, at the expence of letting the cantilever out of center,(or evan if we could get dangerously close to causing damage).
What is particularly fascinating to me is that I have never heard of adding weight for the purpose of modifying the behavior at the cartridge end, but certain evidence shown here seems to support it. That is why, although I believe that to allow the arm to freely with the groove, as opposed to remaining static, is better, I am willing to question it.
Thanks, Zaikesman. I agree that with the low bearing friction, there may be some movement allowed with the mass system. I cannot say that absolutely no lateral movement is present over the groove. But I can definitely say that it is much reduced, because of the results of greater dynamics, crisper detail, and bass I got with it. I may not even have the best ratio, because I did not try a bunch of different weights. But by luck, I got a pretty good result on my first try.

I have thought of making the weight on a threaded shaft, so it could be adjusted for distance from the pivot. This would complicate the prototype, but production would be just as easy. You may have caused a price increase :^). It would certainly be more applicable to a wider range of cartridges with a system like that. But the spread would have to be equal on both sides, or you'll be changing the anti-skate force.

What type of arm are you using, Zaikesman? If you have a way to fix these weights onto your arm, I could send you a set for evaluation on your TT. I know that they easily go onto a Rega arm. I would like to get some feedback on this. I am already sending a set to Nrchy, who has a Rega RB900. And if Basement wants some to try out on his RB300, he can have some too. They don't cost much, I just get them at the fishing store. If you think you could somehow get them onto whatever type of arm you've got, just email me your address, and I'll send a set to you.

By the way, I think that there is a sort of "mass threshold". As an example, if I am lifting weights, and I keep increasing the weight, at some point I won't be able to lift it. The static moment of inertia will be too high for me to overcome. That is the "threshold" that I am looking for with this system. If the mass is higher than the cartridge can overcome with its suspension, then the theoretical infinite mass can be approximated. As long as the arm can still move freely to track the groove spiral. Since the spiral tracking occurs over a long arc, the low friction of the bearing should allow this to occur, but on the quick dynamic spikes of the groove info, this mass should be sufficient to virtually eliminate arm deflection, if the mass is calculated correctly. Do you agree with this hypothesis?
Basement, I wish my eyes were as good as yours. Now that I'm over 45, I can't see up close anymore.

About the off-center records, I don't really see this as a problem, because the mass increase is easily moved during the long arc of an off-center record. The shortest arc that it could have to navigate would be 180 degrees, because the hole is only off-center in one direction from the center. That means that the record will start to move one way for 180 degrees, and start moving back for 180 degrees. On the outside of the LP, if there was 1/8" off-center, the stylus would have to adjust only 1/8" over 19 inches of groove travel(the circumference of a record is about 38 inches). This could hardly be called a rapid movement. The low bearing friction could easily handle this. And 1/8" off-center is a hell of a lot. I personally would not even play a record that bad. None of my records are even close to that far off. I do have some warps though.

Adressing your statement about the "speed of the cantilever", the cantilever is designed to operate at the speeds and distances it will encounter in the RIAA curve that is encoded into the groove. These parameters are known and designed-for by the cartridge makers. I see no way that a well-designed cartridge will be caused to mis-track by the proper orientation of the arm over the groove. If you are saying that the damping or horizontal mass increase will cause the arm not to properly track the off-center record, I have already covered that topic. It can track the off-center record. If the record is so far off-center that a damped arm cannot track it, then that record is junk. I cannot consider items like that in my design. A high-performance Ferrari suspension is not made for going "off road". We have to assume at least a decent level of record quality. I will accept the loss of some defective records, in the pursuit of improving the sound of 99.9% of my collection. The slightly off-center records are not affected by this design.

On the next issue, I agree with all 3 of your points regarding increased mass on tonearms. The problem with cantilever breakage on ET arms is generally attributed to the TT not being level. With the low friction air bearing and the lack of anti-skate on linear arms, leveling is crucial on these arms. The other cause of breakage was the "Groove guard" ridge, that caused a rapid accelleration of the stylus into the lead-in groove, as it slid down the side of the "Groove guard" ridge. This is why many recommended the starting of play after the first groove into the first song, with these arms. Fluid damping reduced these hazards. These are cases of "runaway, out of control mass" as we talked about in the previous posts. On pivot arms, this is less problematic since there is usually higher bearing friction in these, as well as an anti-skating mechanism. However the "Groove guard" can be a pain in the ass, at times.

Continuing to address your points. The use of fluid damping in addition to horizontal mass increase is not out of the question. It may be a good combination for reasons previously stated. I have not tried it yet. I have already addressed that I don't think that there is any possibility of damaging the cantilever with any of these systems. We want the cantilever to move as much as needed to retrieve the info off the record, and no more. If the cantilever is stiff enough to not bend under these stresses(no cantilever should bend), then these methods of keeping the cartridge centered should only help matters. It is the mass of the arm moving away from groove-center that may damage the cantilever. None of these systems allow the cartridge to move off groove center, even on off-center records, as previously stated. The entire purpose of these mods is to keep the cartridge groove-centered in all circumstances. I really don't follow your point of saying that these mods will cause/allow the opposite of their intended purpose. They do not impede the long slow movement of the arm during tracing of the groove spiral, or even off-center records. They only stablize the cart/arm during quick movements of the stylus, particularly during dynamic bass activity. If you are seeing your cantilever moving sideways because of an off-center record, then your cartridge is too high compliance for your arm. Or your records are really bad. What kind of cartridge are you using? This may be the reason why you had dead sound when you increased the mass. If you have a med-high compliance cart, your arm may already have enough mass to provide stabilization. If you can see your cantilever moving off groove-center, then something is drastically wrong.

Regarding your last sentence, I am not promoting the idea of preventing the arm from moving with the groove spiral. I want it to move with the groove spiral. I just want the arm/cart to remain centered over the groove while it is moving with the groove spiral. This is the aim and purpose of my mod. Remaining centered with the groove, and still being able to move enough to trace the spiral, is not a mutually exclusive combination. It can do both, and do it quite well. And it does not carry with it any greater danger of breaking the cantilever.

I wanted to offer you some of my weights to put on your RB300, but now I'm not sure if your cartridge can handle them with the records you are playing. Tell us what cartridge you have. If I think you can benefit from these, you are welcome to them. I am a little concerned right now that you might be over-weighted as it is now.
Time to go watch "The Sopranos", so I'm being brief. Basement & Twl, my TT/arm was mentioned above (OK, way above), but it is a garden variety Technics SL-1200 with its stock arm. Also as mentioned before, the damper will be from KAB, and it is specifically designed for the Technics (the KAB website has some interesting stuff - check it out). FWIW, the arm is about 11-12g, I believe, which is supposed to mate fine with my B-M Glider M2. If you are familiar with this design, Twl (and who isn't?), you will know that there is no way a weight could be attached to the left side of the horizontal axle, because the sideways-U shaped bracket that fixes the upper vertical bearing is in the way. I'll have to get back to you on the other stuff after the show. :-)
KAB is a pretty cool site. That fluid damper rig looks like it will work fine, and it looks real "factory" like. Very clean and professional. It seems to me that they are primarily promoting a vertical damping, but it appears from the photo that the paddle can be rotated to provide a lateral damping effect. I expect that this will make an improvement in sound quality on your 1200. Let us know. I am sending a set of these weights to Nrchy tomorrow, so we can get some feedback on how they work on his Sota/RB900 system. He's got a Benz Glider with a 15cu compliance, so we'll see how this works with a medium compliance cartridge on a Rega arm.
You know, it's been so long since I took a look at the KAB site, I guess I forgot which plane the damping operates in. Considering that the grooves are actually cut at a 45 degree angle, I would suppose that a little of both horizontal and vertical damping would be a good idea (which ties in well with my idealized theoretical above). I'll make a point of asking Kevin at KAB about this aspect.

As far as the threshold hypothesis goes, I can't agree with your analogy about lifting a weight. Weight is not the issue here, mass is. If the weight you couldn't lift was floating in space, and you attempted to push it away from you, you would move both move in opposite directions, according to your respective masses. In theory, when you or I jump up in the air, our push-off sends Earth moving infitesimally in the other direction; there is no real threshold - a practical one, yes, but no absolute one. Or to put another spin (sorry again) on it, if the arm was really so massive that the cantilever's suspension couldn't overcome its mass to move it when transcribing a groove modulation, then it also couldn't move it across the record as it played - the suspension would just keep deflecting until something gave way. If a force applied at the stylus can move the arm at all, then it can move the arm period.
TWL, I think we are having some misinterpritations here, but when we are speculating, as I am, that will often be the case.
I agree with you on all your reasons and speculations behind your mod. I also find them highly intelligent and insightful. I also understand that you are looking for superior tracking. I get the idea that you think that I was implying you weren't. I think that our separation in understanding is in the flexing of the cantilever and the speed that I am refering to. Or, if you will, the offset from perfectly center that is encountered in the circumstances of cantilever flexing.
The speed I am refering to is the warp/wow frequency and the lowest bass frequency. The amount of movement I am refering to are very, very slight. At the level of evan a fraction of a cantilever width. I am not trying to imply that because I can see it, that it exist, or that it doesn't exist if I can't, I use my eyes as an aid. The cartridge I am using is a clavis d.c., and as you know, the arms are an older model immedia and a rb-300. I do observe movement in both, but I don't consider it unusual movement or out of spec. Just to be clear on what I use my eyes for, if I see movement, I use that for a clue, or try to find clues by looking for movement, and then I attempt to identify what I am seeing by checking the set-up and listening.
When the complience and mass of an arm are considered matched, the resonent frequency is suppossed to be between the warp/wow frequency and the lowest bass frequency, I beleive that is 5-10 khz's. THAT is the movement I am refering to. This happens as the cantilever is moving to track the record, which is determined by the mass and complience of the set-up. How much it moves and how fast it moves are two different things, I leave it open for debate as to how much, as I don't know. I know that in most proper set-ups, there is movement, and that it is desired by traditional thinking to minimize it. (I'm still refering to the amount of movement, not the frequency).
While I suggest that your canilever is moving, I am not saying that it is mistracking-the contrary. I have to suggest that it is moving more than it was because by adding weight to a given application and changing nothing else there should be more movement in the cantilever, and that is based on having the arm remain more static than it was. I don't mean to imply that it is more static than it should be, or that there is more deflection than there should be, but I do contend that at the extreme of such an experiment that there will. I am forced to consider, however, that if you increased the amount of movement but changed the other parameters, such as the frequency, or other things that I am not aware, that superior results are/were gained from your experiment at the expence of greater movement at the cantilever. Please don't take that as me saying that you are ignoring movement there, Or that you are not looking to minimize it, or that you shouldn't, but if you don't consider what movement is taking place, or what could take place, then I don't think we can be able to asses the differences that are taking place.
The way I see this, is that adding mass of that amount in the horizontal plane is unconventional thinking, evan as the theory and evidence for it may be sound. I also believe that your assessment of the improvements in sound are true, as I would say from what I have learned from you I would have to guess you are quite competent in that area. All of the evidence that I keep learning as I explore this is leading to this not only being the case, but is causing me to have to stretch in my understanding of tonearms. So I might stretch your theories.
Basement, first, if you would like a set of these weights for your RB300, email me. They should make an improvment on the Clavis. That is not a "whippy" cartridge, and the cantilver/suspension should be quite stiff. These weights are easy to apply, and stay put, in just the right place. I really would like your feedback on this.

Next, I think I am beginning to understand what you are saying. One thing that needs clarification is your term "cantilever flexing". Is the cantilever actually flexing, or is it just moving in its rubber suspension? This is an important difference. The cantilever itself is a stiff tube, and should not flex. Flexing loses information, and imparts an unwanted resonance in the system. If the movement you refer to is small, and near the center, then it is actually suspension movement you are seeing. Flex, if it does occur, would only happen at the end of suspension travel.

If I understand you correctly, and correct me if I'm wrong, you are concerned with the very low frequencies that may be caused by warp/wow in the range below 10Hz. You feel that if the cartridge is actually tracking these frequencies, that it may be detrimental to the system, and the cantilever especially. This is because you feel that the large movements that occur at this range may bend or break the cantilever, and these frequencies should be prevented from entering the system anyway. Right? And your concern leads you to believe that the arm should move laterally at these frequencies to relieve the sidewards stress on the cantilever, and to preclude these frequencies from entering the signal chain. Right? Tell me if I understand this the way you mean it.

Now, going on the assumption that I understand correctly, you are actually referring to the matchup of the lateral effective mass/cartridge compliance. If it is minor warp or off center problems, yes the arm should move laterally on the bearing to account for these eccentricities. These problems are slow dynamics compared to the rapid lateral accellerations of the stylus during tracking of low frequency playback dynamics. An object has much more resistance to movement when a rapid accelleration is applied, than when a slow push is applied(Force=Mass x Acceleration). The slow movement of the record groove during warps and off center travel is easily handled by the arm bearing, and the arm moves laterally quite easily in this circumstance. If you are saying that the warp/off center record is causing a quick massive 1/4" or more movement that causes the weight of the arm to stay in place, and makes the cantilever move dramatically sideways because the record movement is too fast for the arm to keep up with it, then that record is a Frisbee, not a record.

My theory on this issue is this. The transducer should respond all the way down to DC. All frequencies begin at DC at the beginning of the attack, and quickly rise to the fundamental tone, and then decay back down to DC again. This is the structure of all notes. If we avoid the reproduction of the lowest octave, then we change the structure of the note, as we hear it. Even if the rest of the system cannot reproduce this, it has its effect on the sound. It is an attack, sustain, decay, timing issue. The resonant frequencies in the cartridge/tonearm cannot be avoided, but can be tuned out of the most offensive areas.

So, IMO to purposely allow the tonearm to move laterally at these frequencies, for the purpose of avoiding their reproduction, as a preventative of cantilever stress, is a counterproductive measure. It is my view that all frequencies from DC and up, should be included in the information chain of the source transducer, regardless if the other elements in the signal chain can reproduce them or not. If not, the natural structure of the tones, and the PRaT will suffer.

So, to sum up on this subject, I feel that the cantilever should be subjected to all these forces, but should remain in its properly centered relationship with the groove at all times, if possible. This may not be entirely possible, but it is a goal that we should try to attain with the improvements we are considering.

If the record is defective or warp damaged to the point of causing extraneous peaks in the frequency response at very low frequencies,or causing undue stress to the cantilever, that is a problem with the record, not the playback system. The playback system should track all the information on the record, if we are to even hope to get the best reproduction.

Regarding my unconventional thinking, it may be somewhat unconventional, but it is not original, or new. Others, such as Dynavector have addressed this directly, with an entire design(the 505-507 series) with this idea as the goal. And Graham, as well as other unipivot makers are using some form of this also. The Transcriptors Vestigal arm, addressed inertia and had 35 times more lateral inertia than vertical inertia. And the Vestigal was made in the 70's.

Hopefully, I have understood your idea, and have addressed some of the points you raised. If not, please re-explain, and I will try again.
Oh yes, I gotta try the weights. I would highly appreciate a set of yours, as then I can be sure I am trying exactly what you are using.
My statements regarding cantilever flex are exactly as you say. It is not actually the cantilever that is flexing, but the suspension. That can get confusing. I dont know or remember what that peice is called that the cantilever is attached to, that peice of wire, but anyway, I am observing the movement at the center more or less as you desribe.
The warp/wow that I am refering to is not nessessarily something that I would expect to tame, but the way I understand it, all combonations of arm mass and complience have or produce a resonent frequency, a frequency that is the natural frequency that will cause them to vibrate in sympathy. That is why usually the goal is to set that between the lowest frequency produced by the record, (or for clarification, the music or noise pressed into the record) and above the frequency of the warp/wow.
If the resonent frequency is in a place that is likely to get "exited" then that may have a tendancy to mask or alter the information we want.
I'm not sure if this is conventional, but I am trying to define that there is a difference in the speed of the cantilever movement and the amount of movement altogether.
I'll try to dig up some references so I can be more accurate in my descriptions and definitions, and also you can see what you think if I can find them and get some to you. I also seem to remember the SME use to have a damping trough available, so I'll have to see if any are available. The KAB site I checked out, and the damping trough seemed as though it would require quite a bit of modification for use on a rega, and zaikesman, if you are reading this, it will be very interesting to hear what this does for you.
I also think it would be interesting for us to try and measure these things. If anyone has any info on what is required, I would be extremely interested.
Yes, there is a difference in cantilver speed, depending on the frequency of the "bumps" in the groove that it is trying to trace. Larger amplitude bumps, in the lower frequencies, require faster velocity than the smaller "bumps" in the high frequencies, because there is more lateral deflection and return, for a given amount of rotation of the record. Also, the speed differs at the outside of the record, and the inside. The record is larger diameter at the outside, and therefore has different speed at those grooves, than the inside.
Also, I feel that the warp excitation of the mass/resonance is far less critical in the horizontal plane, because the warp movement is primarily in the vertical plane, and that is not being changed by this mod.

As an experiment last night, I played an extremely good recording by John Klemmer, recorded direct-to-disk on virgin vinyl. This beautiful record suffers from some of the most complex warping of any record in my collection. It has a dish warp, and several varying radius warps all around the perimeter(a real shame). However, I played this record on my TT(with the weight mod on the arm) and I found that the arm tracked the warps very well, and also the slight out-of-round that was there. The only noticeable thing was the woofer cones were bouncing, like would normally happen on a large warp anyway. Believe it or not, even with the intermod that this woofer bounce makes, the sound of this recording is unbelievably good, and the cartridge tracked even the most difficult dynamics like a train on a track. So as far as I can see, this does not hinder the vertical performance of the arm at all. And it shouldn't, because the design is only applied on the horizontal performance parameters. This arm with my mod, was able to track the most difficult warped record I have, and provide awesome audiophile sound quality and tracking while doing it. Just for fun, I turned on the CD player, and played one of my CD's, while I was making a cup of coffee, and it sounded like the system was broke! The sound of this TT, makes a very good CD player sound like something is wrong with it. A good record on this TT absolutely destroys a CD player, even with my best CD. Like I said, the Sony 9000ES CD player sounds like it has something wrong with it, in comparison to this TT setup. If anyone ever came over here, and listened to that comparison, they would laugh out loud.
I'm glad you tried the warped record. I'm having trouble trying to explain what I mean as far as the amplitude of the movement and the amount. I'm trying to think of the proper terminolgy, bot I'm at a loss, as I have been, but I'll try to get closer. I have a feeling you might already be aware, you just can't understand the way I am attempting to explain it, so here it goes. I'll use extremes.
Say you had your anti-skate so off that it caused your cantilever to be way off to one side, (ignore all the obvious mistrackings for the sake of explaining). It would not cause movement of your bass drivers because the cantilever would be fixed. The cantilever has to be in motion, no matter how fast or slow, to cause a signal. (evan one you can see, such as movement of the woofer, but can't hear)
But if the cantilever were to move slow enough, no matter how far from center, there could be still no signal.
So while the movement of the woofer, in real use moves for something like the duration of the movement of the cantilever, it is actually the speed (technically the frequency) that is causing the woofer to move.
To get back to real life for a moment, In playing that frisby, you were able to actually observe the movement of the woofer and still get exceptional sound, yes? That indicates a good macth between cartridge complience and arm, as the warp/wow frequency was obviously present and did not affect the sound quality by causing an unwanted resonence that would interfere with the frequencies you were listening to.
You are right about this, I'm sure of- we will not ever be able to eliminate the warp/wow frequency. It will always be present and the cartridge will always be able to pick it up.
Were you able to observe movement in the catilever/suspention while this was happening? Also, are you sure that the woofers were moving to the sideways motion and not the vertical? In fact, if you follow what I am attempting to communicate, I wonder if you could observe movement of the woofer while not observing movement of the cantilever, and visa-versa.
Let me know if I am coming across, or the proper terminology whatever it is. I can't actually ever recall such a discussion ever taking place. I have more and more questions, but I don't want to confuse things to much just yet.
I found in an issue of stereophile, april 1996, (vol 19 no 4) in the review of the clavis d.c., MF gives a very thorough account of the inner workings or cartridges, this one particularly. He names many of the parts, except what that thing is called that is in front that the cantilever shoots through. It may not relate to our topic, but it may be interesting to you, evan if it may be redundant, so you could tell me more properly what the heck I'm talking about.
Yes, Basement I am beginning to get your drift. The stylus/cantilever must move in order for a signal to be generated. Simply having the cantilever out of line, doesn't necessarily generate a signal. But if it is out of line, then when a signal is traced, the coils will be out of center and a channel balance problem will be heard. Also the maximum deflection ability of the cart will be impaired in the direction of the side that it is off-center towards. This is a bad condition, and should be avoided. It will also cause increased record wear on one side of the groove.

The warped record I played had mostly vertical movement, and so I'm sure it was the vertical play that caused the woofer movement. I didn't try to see if the cartridge riding the warps coincided exactly with the woofer movement, although I am sure that is what was causing it. The record sounded terriffic, even though the warps were pretty bad.

The "thing that the cantilever sticks through" is called the suspension ring or donut. It is a rubber ring that is set to flex at a particular rate for the cartridge design. Butyl rubber is considered on of the best, but many types of rubber are used.

Don't forget to email me your shipping address, or I can't send you these weights.
Basement, I believe you refering to the yoke.

I am getting a little lost as to where exactly this conversation is now heading, but I will make a couple of observations and hope that they will be relevant (at least to what has been written above, if not to anything important in actual practice).

1) Information in the circa 10Hz range is not intended to be transcribed in the grooves, having been mastered out beforehand. Content in this range is usually limited to warps which are vertical in nature, although a cutting lathe can inscribe rumble of its own, unrelated to the musical signal and horizontally cut.

2) The RIAA curve dictates that bass information is transcribed in the grooves at a much reduced amplitude when the record is cut, then boosted back to flat by the phono preamplifier. So these frequencies do not represent a high physical amplitude at the surface of the record.

3) As Basement implies, DC = an unmodulated groove, i.e., no signal at all. An amp will generally not pass DC, and a loudspeaker does not produce an output from a DC input. Which is to say that there is little pertinence in the notion of 'flat to DC', IMO.

4) Twl's statement about the attack of a tone rising to its fundamental before falling back to DC doesn't jibe with my own understanding. To the best of my knowledge, the attack of an ideal transient event, were it reproduced perfectly in theory, would rise in a straight vertical line over no elapsed time to a frequency = infinity, before falling back smoothly to the fundamental. In practice, transients rise very fast, over a very small span of time, to a very high frequency, before falling quickly but with some ringing back toward the fundamental.

OK, moving right along...

Kevin at KAB is sending me my damper assembly (you still here, Psychicanimal?), so I should have that in hand in a few days. He says that the paddle (which, BTW, is sourced from SME) is curved, and therefore has a damping component in both planes, although he says the vertical predominates - we'll see if that is my impression as well once I actually get it installed. Also, he says there are other paddle profiles available from SME. We had a long and interesting conversation, during which I suggested a product idea he is taking under consideration (completely unrelated to yours, Twl), and I will keep you informed if this goes further (it would likely be only of marginal interest, if at all, to folks on this forum in any case).

Awaiting Nrchy's beta-test results whenever he's a go...
Zaikesman, I think we are all a little lost here in this, but that is what I think makes this worthwhile-A better, more sophisticated comprehention of what habbens in this area, which I think is aat the fundamentals of what makes a tonearm work well. Regarding the unmodulated groove, and the output happening in that region, is yes, caused or modulated by the warp, not something pressed into the record.
I think where TWL is on this, that I tend to agree with, is that the cartridge will, and should, be capable of reproducing this, evan as it is artificailly produced by the warp. My guess, which I'm not sure is correct, is that because it is produced does not nessesarily mean that is the resonent frequency produced by the arm/cartridge combo, but am I wrong?
Regarding the transient that you just spoke of, I don't understand this, but it may be what I am trying to understand. Could you please explain with more?
Oh, I almost forgot, the yoke, what part is that? TWL, the peice I was refering to was not the suspention component, that metal piece with the big hole in it, the one you have to look through to see the coils, often made of brass?
Well Basement, that sounds like the yoke, which would be the piece that holds the suspension donut.

About reproducing the warp, if the cartridge is held properly in place, and is doing what it is supposed to do, it will reproduce anything that excites the stylus. If that happens to be a warp, then that's what you'll get. If the cartridge is allowed to do anything else, then you will lose additional information than what you are trying to preclude from entering the system.

About the RIAA curve, the things Zaikesman said are accurate, although the bass info is still the largest bumps in the groove from what I have heard on the subject.

There is some disagreement on my "all notes start at DC" theory, but I think that is a subject for another thread.

Zaikesman, Good luck with the stuff you're doing with KAB. I hope you can get some good stuff going with them for your TT.
Alright PsychicA, here you go...

(I'm going to post a version of this report as a separate review as well, since that's essentially what it is, but I do not want to remove it completely from Twl's long-running thread, so here it is in its entirety to continue the conversation - I hope Audiogon doesn't object!)

I got my KAB fluid damper kit for the Technics SL-1200 installed yesterday, and I managed to audition one cut twice in close proximity both with and without the damper, by playing it just before I put the silicone in the trough, and again just afterwards. I also replayed a few other things with the damper activated which I had just played the day before without. So these are my very initial impressions, and since I'm writing this after only one day, I'll have to post any further findings another time if need be.

First of all, let me say that this damper is a very nicely turned-out product, and it doesn't detract in any way from the appearance or operation of my SL-1200, but at half the price I originally paid for my whole TT/'arm new back in the 80's, there's not a lot of perceived value at $150 when you crack open the small foam-lined plastic box and find a little curved machined metal tray (embedded with a set screw for attachment to the 'arm's base, etched with the KAB logo, and painted silver to match the 1200), a tiny plastic paddle with an integral collar and thumbscrew to tighten onto the 'arm (sourced from SME), a syringe of goopy fluid for filling the trough with (sans replaceable cap for storage, an ommission KAB should rectify), some fairly prefunctory instructions, and a hex key, although I don't doubt that KAB's return is fair on this quite specialized accessory. I was unprepared for just how viscous the 'viscous fluid' really was, never having used this type of damper before - that gunk be seriously thick.

In addition, I noted that the paddle which attaches to the tonearm presented less of a resistive 'face' to the fluid contained by the trough in the directions of motion (horizontal and vertical) than I was expecting might be the case (the KAB website has some good new pictures up of the damper in set-up and operation). Its broad side is a bit curved though, in the opposite direction of the curve about the pivot point made by the trough, and it is oriented at a slight angle to both the 'arm's arcing path of horizontal movement through the trough, and to the vertical component of a record warp, since it's not installed pointing straight down from the 'arm, but is offset about 10 degrees toward the direction of the platter.

Let me also just list briefly the audio chain I am listening to this gizmo through:

Benz-Micro Glider M2 .8mv MC cartridge > Technics SL-1200 TT and 'arm (modified with: Symposium shelf underneath sitting on Focalpods soft footers, Michell delrin record clamp, MusicDirect polymer tonearm wrap, and Sorbothane replacement mat) > Camelot Technologies Lancelot battery-powered op-amp phonostage with 54dB gain (modified with 392-ohm Vishay VHS loading resistors and resting on Audioquest Sorbothane pucks) > Cardas Cross 1m RCA IC > InnerSound FET preamp (with Synergistic Research Master A/C Coupler PC) > Harmonic Technology Magic One 1.5m RCA IC > VTL MB-185 Signature circa-200w all-tube monoblocks (with Shunyata PowerSnakes Sidewinder PCs) > Cardas Cross 8ft speaker cable > Thiel CS2.2 3-way floorstanding full-range speakers > and all electronics fed from Audio Power Industries PowerWedge Ultra 116 PLC (balanced AC to front-end components) and supported on a Salamander Synergy Twin 40 rack. Everything is set up a comfortable distance away from walls in a medium-sized living room, with the listening distance being about 10ft.

I listened to three disks from the 60s, acoustic jazz from the Jazz Crusaders LP Uh-Huh, rock from The Who LP Sell Out, and pop from Gary Lewis & The Playboys LP New Directions, and two from the 70s, acoustic jazz from the McCoy Tyner LP Extensions, and rock from the Richard Lloyd LP Alchemy. The Jazz Crusaders 9 1/2 minute cut entitled "Blue Monday" was the track critically auditioned back-to-back first without and then with the damper. Differences noted with the damper in use were pretty consistent across all the cuts I auditioned.

OK, now to the listening. As a preface, let me say that I wasn't expecting huge changes, and I didn't hear huge changes. After all, everything else is staying the same besides the addition of the damper and paddle, so why shouldn't it sound more similar than dissimilar to the sound I have come to expect? I haven't listened for long yet, but I think I do already have a pretty good handle on what this product is going to do for the sound.

I certainly did look foward to some degree of positive improvements for my investment. However, as is often the case in actual practice, the improvements I got turned out to be not the ones I necessarily had in mind when I ordered my unit. I suppose after years of making step-by-step upgrades to my system, I should be better prepared at this point as to just what to anticipate for the next tweak or change. Yet I still manage somehow to be surprised as often as not, a situation which is funny to me, because there are definite similarities underlying a lot of the fundamental improvements I have experienced in the past - such as the principle Less Is Sometimes More.

I decided to acquire this tweak based partly on a set of expectations I had intuited from my deductions about how such a thing must work in operation. I reasoned, if the damper prevents the 'arm from dissapting as unwanted motion energy which should instead be going into forcing the stylus to faithfully transcribe the groove, then I should hear 'more'. More impressive dynamic peaks, more bass slam and weight, more soundstage space, more transient impact, maybe even a little more overall volume. There were a couple of things I was hoping for less of - less surface noise, less HF grain, although I wasn't consciously aware of any objectionable presence of the latter. KAB's inscription on the damper's box promises "deeper bass" and "clearer midrange", as well as "improved tracking", and Kevin A. Barrett (KAB) also mentioned that customers sometimes find more of a sense of 'time slowing down' when listening with the damper fitted, though I don't personally tend to subscribe to such notions myself.

Well, if I had been expecting 'more', in many ways 'less' is what I got, and the things I did get more of were generally not what I had suspected beforehand. In retrospect, everything I heard does make sense given what the damper ought to be doing, but it definitely took my experiencing it to arrive at that conclusion. The very first things I noticed when listening with the damper activated were the cymbals on The Jazz Crusaders cut. They were exhibiting greater HF extension now, and were noticeably smoother. I wasn't expecting that, but I liked it.

I tried to listen for deeper bass, or more explosive transients, but couldn't find them. The soundstage didn't really seem any more expansive than before. The horns did sound a little less foward now, though. When the piano solo came on, I realized that an obsidian-like sort of dark glassiness that had somewhat shrouded the instrument before, had been replaced with a more open, pillowy-natural gentleness as the keys were being purposefully tickled from the outside left rear of the soundstage. When the stand-up bass solo followed, the centered image floated in space just as effectively as before, but had lost a certain talky, PA-like quality to the sound of fingers on strings which had previously rendered it as more of an electronic reproduction of a bass, and instead sounded more naked and true.

I slowly started to realize that although the soundstage wasn't any 'bigger'-seeming, it was effectively deeper, because I could now 'focus my ears', so to speak, more precisely all the way to the backmost reaches and still maintain the sense of clarity and definition. It began to dawn on me that, instead of enhancing the leading edges of transients, what was actually happening was a cleaning-up of their after-effects. Everything within the soundstage was less perturbed by everything else.

Rather than seem incrementally louder, the overall volume, if anything, was actually slightly subdued with the damper doing its thing. But added background texture was reduced even futher, resulting in an apparent universal improvement in S/N ratio. I'm not talking about surface noise as such here, which I didn't notice too much one way or another on these relatively clean disks, but a reduction in what must surely be the artifacts of spurious vibrations and their reflections. The whole presentation sounded tidier, tighter, and clearer, the ever-so-slightly reduced apparent amplitude probably a function of the effective subtraction of reradiated stored energy in the form of ringing. Less is more.

Dynamic events taking place in different areas of the soundstage had less of an effect on one another, permitting the instruments to go about their business without smearing or the imposition of added harshness as compared to before. The result, prehaps paradoxically, was to make gains for my analog reproduction resembling some of the more favorable attributes of CD, for aspects such as separation and contrast, while at the same time actually adding liquidity through the removal of intermodulation. Decays, not the onsets, of transients were the big winners with the damper in place, exhibiting a newfound cleanliness and precision that allowed me follow the flow the music with less guesswork. Image focus became more crystalline-pure and unwaveringly stable, less prone to fluctuate with attacks and crescendos. Although I'm not big on the concept of 'pace', I would actually say that, if anything, the music now seemed to move along at a slightly brisker clip, unencumbered by the dragging disturbance of throwing a larger wake in its trail.

In the big picture, I'd characterize the changes wought by the addition of the fluid damper as being on the order of about 10% or so (quite good), but in the particular areas upon which it has its greatest effects, I'd say they were more like 50%, which I think is excellent. No, I didn't get 'more' bass or dynamics, but I got less of what the presence of such information in the grooves can do to the more fragile parts of the sonic tapestry. In my estimation, what I'm hearing now with the damper is more faithful to the music mastered into the vinyl than what I was extracting previously, mostly through the reduction (if not the outright elimination) of some of the more pernicious effects engendered by the process of attempting to trace microscopic squiggles with a flexibly mounted needle attached to the end of a freely swinging arm.

I have not yet tried to ascertain the improvements wrought, if any, on the trackability of warped records, or the possible effects of the damper on reducing susceptability high-level acoustic feedback, for instance, but I will post updates when/if further developments make themselves known to me. For now I am exploring and enjoying the smoother and cleaner ride through the grooves the KAB damper is affording my cartridge and tonearm.
Zaik, you're too much!!!

Yes, you got it right--the fluid damper makes the LPs sound closer to the attributes of CDs. This parragraph wraps it all:

"Dynamic events taking place in different areas of the soundstage had less of an effect on one another, permitting the instruments to go about their business without smearing or the imposition of added harshness as compared to before. The result, prehaps paradoxically, was to make gains for my analog reproduction resembling some of the more favorable attributes of CD, for aspects such as separation and contrast, while at the same time actually adding liquidity through the removal of intermodulation. Decays, not the onsets, of transients were the big winners with the damper in place, exhibiting a newfound cleanliness and precision that allowed me follow the flow the music with less guesswork. Image focus became more crystalline-pure and unwaveringly stable, less prone to fluctuate with attacks and crescendos. Although I'm not big on the concept of 'pace', I would actually say that, if anything, the music now seemed to move along at a slightly brisker clip, unencumbered by the dragging disturbance of throwing a larger wake in its trail."

And *that* it's why the damper makes things 'slow down'...there's sooo much music now it seems to warp time!!!

I didn't want to tell you this benefit, for fear of you stigmatizing me as a nut.

Glad you liked it. I think you listened to it too clinically--like a reviewer. Next time get a hold of your favorite "beverage" and/or smokes, relax and enjoy!!!

Get a hold of some funky salsa records...

Adding the Bob Regal foot next to the tonearm gimbal brings more improvement on the bass than the damper, BTW.
Just to keep things perking along here, while we wait for Twl's beta testers to ring in, I remembered a thought recently which first occurred to me quite some time ago, concerning the Dyna 'arm design discussed above.

I actually had this design idea come to me in a dream (talking now about separated pivot points for the horizontal and vertical components, with the vertical bearing being closer to the cartridge), believe it or not, but realized after I woke up that it was merely a variation on the Dynavector. However, this dream was not about the possibility of increasing the horizontal mass per se.

My dream was inspired by the idea of making such a design in order to greatly increase the tonearm length, for more correct tracing of the groove, and therefore lower distortion, by comensurately reducing the angle errors inherent in any pivoted 'arm, while still maintaining a low vertical mass. This remains a valid concept, but one which Dyna declines to exploit in their normal-length 'arm. One could conceivably employ this type of design to make an 'arm, say, 30" long (with the naturally increased horizontal mass that would come from such a long 'arm), and still achieve a low vertical moving mass by placing that bearing point at a more conventional distance from the cartridge. Such a design would address Twl's theory about higher horizontal mass, while offering tracing accuracy much closer to a linear-tracking 'arm. (It would also allow - indeed, require - the decoupling of the 'armbase from the plinth, something which carries with it both potential advantages and disadvantages, or at least inconveniences.)
That is an interesting concept Zaikesman. I would attack that in a high rigidity approach. Possibly like a wishbone suspension arm made of carbon fiber and wide spacing at the pivot area, and coming to a "V" at the forward area, where the bearing set for the vertically moving arm would be. The counterweight could then be located between the "V" arms, since there would be much less offset angle. In fact, if you could adjust the bearings close enough, you could use 2 unequal length vertically moving arms, and achieve a "automobile suspension" method of keeping the headshell level, even while tracking a warp. Eliminating VTA changes as it rides the warp. This increases complexity, but sounds like a cool idea.

Now if we could only come up with an idea that would allow us to play scratched records without clicking or skipping, we would really make a million.

Still no word from the Beta testers.
That is an interesting point. You have strange dreams. Do you ever have dreams where you take an rb-250, cut the armtube and put the lead between the two pieces to make it longer?
Actually, seriously, that is a good point. It makes me want to measure this all that much more. It doesn't seem like it would be too hard to measure the differences betwwen the amount of mass as far as their effect, but I am having limited succes learning how. I got a line on a occilascope, but it will have to wait a couple months. I also heard that you could get a computer program and an a/d converter, but I haven't checked that out.
It would be pretty easy to make an armboard, or make more/other appropriate parts I would think, For me I think the hard part would be figuring out how long to make it and figuring the placement of the mass. Actually, figuring out what exactly the mass is doing in a way that could be calculated.
I have to agree with Tom's original statement about him being a little strange. I thought this idea was also a little strange, but since I've corresponded with TWL in the past and I have an arm with which this tweak would work, I contacted him and asked about it. I had to drive to his remote mountain hideout and kidnap some of his cats before he would agree to let me try his invention.
First I sat down and listened to an old favorite. Then I attatched the lead wieghts to my Rega RB 900 arm and sat down for a second run through the same LP. It was a MFSL lp which they claim is able to survive repeated listening. I'm still puzzled about how to explain what I heard the second time around. The strangest aspect of change was the fact that I had to turn down the volume on my pre-amp?!? By the time I was through the first two tracks the differences were more obvious. The soundstage was much different. It wasn't deeper in the sense that it went farther back but it came out farther toward the listening chair. I don't think the soundstage was wider than before but it seems to disipate more gradually. There appears to be more height too. I'm talking about inches not feet, but it's noticeable. And the air! There is much more air around voices and instruments. The LP I listened to had some good Grand Piano and bells. The first time through I noticed them but they were nothing special. The second time there was soo much more presense and authority to them. The bells actually startled me. I expected them, but I did not expect how *real* they were going to sound.
I know this sounds crazy. I'm having a hard time believing it, and I heard it!
TWL is on to something here. I don't know much about the technical aspects of this mod and I know nothing about how it would measure but I told you how it sounds. Go figure!

I have no idea how much the parts and labor would cost to produce this tweak for mass consumption, but for me to buy an arm that sounded that much better than my already good RB 900 would set me back well over $1000. If I could sell my arm for $500 I'd still have to come up with another $700 to $1000 for the better arm. If I could buy this tweak from TWL for $100 I'd be making out like a bandit!
Actually, Nrchy, what Twl said was that he was 'a little different' (than what, I don't know); *You* said he was a little strange (but who am I to aurgue?). ;^)

I find it very interesting [Sorry to interupt, but y'know, whenever I see that phrase, 'very interesting', around here (and I use it a lot), I can't help but say it to myself in that faux-German voice Artie Johnson said it in on Laugh-In as he peered through the bushes with his binoculars. Do you think I have a problem? Or maybe I'm just...'a little strange'?] Uhmm, where was I - Oh yes, I find it very interesting that Nrchy and I have seemingly arrived at fairly divergent sonic assessments regarding the tweaks we enacted (I just went back up top to reread Twl's original post, but all he specifically remarks on is increased 'dynamics and detail'). This could lead one to believe that the two tweaks (horizontal mass-increase damping, and fluid damping) are really not that closely related in the ways which they operate. Thinking about it, I'm actually surprised no one has offered (to the best of my knowledge) a retrofittable fluid-damping kit for Rega 'arms, considering how ubiquitous the design is. Another market?

Twl, your idea about the VTA-correcting double-hinged 'arm, while not persuasive to me as such (wasn't it you who said something to me, someplace earlier up this thread, about not getting too complicated - besides, I'm still not convinced that a momentary VTA error of a few degrees during a warp is really a big deal), reminds me of another variation on this theme. I believe I remember a design, probably from the 70's, and probably not all that up-market (although I can't think of who actually may have made this for the life of me), wherein the headshell was hinged on a bearing permitting it to rotate in the horizontal plane, and a separately-pivoted (from the tonearm) 'control arm' was employed, not quite parallel to the tonearm but running alongside it on the outside and swivel-attached at the headshell, for constant correction of the headshell's offset angle as the tonearm moved across the record, through a slight 'parallelogram-ing' action. Anybody know what I'm talking about here ('cause I'm not at all certain that I do!)? I do agree, Twl, that something along the lines of a wishbone, truss, or I-beam design would have to be enlisted to make an extra-long tonearm as rigid and non-resonant as it would need to be.
Nate, I'm very happy the mod was effective for your application. This lets me know that the mod is applicable for different compliance ranges, and that is good. My initial assessment of your results compared with mine, is that your compliance is higher, so the bass dynamics were not as affected as mine(lower compliance)was,but the general information pickup was improved. With my stiff compliance, the arm is more likely to be pushed around by the stiff suspension on the cantilever. But the fine detail, air, and authority of piano,bell-sounds, and such, is also improved on my arm with the mod. So now we know that it works on an OL Silver with DL103, and RB900 with Benz Glider. Basement's rig is a RB300 with a Lyra Clavis, so we'll see how that one does.

See, sometimes being a "guinea-pig" Beta tester can be very advantageous. You are presently the only other person in the world with this mod, besides me. Basement is the next victim, and his test units are going out in the mail today. I couldn't go down to the store to get more weights until yesterday. :^)
Zaikesman, the articulated arm you referred to was the Garrard Zero-100 Zero Tracking Error system. I had one of those in the early 70's. The main problems were cheap construction and implementation. The system itself could work with modern materials like carbon fiber and a quality implementation.

I would agree with your assessment that the fluid damping and the horizontal mass modification seem to have different characteristics, even though we speculated that they might have similar ones. Perhaps a combo of these two might prove to be beneficial.

Yes, I knew that a 4-8 bearing setup on a double wishbone for the headshell would be overly complicated, but I was just dreaming about the exotic. I also dreamed about using a Buckminster Fuller tensegrity column for the arm, in which all forces would be resolved in the tension/compression design. Way too complex, but fun to think about, if you are "strange" like me.
Just to make an announcement, this mod now has an official name. It is called the HI-FI(Horizontal Inertial Force Increaser). Assuming a positive response from Basement, I will begin to look into a market for these products.
I've always wanted to see a tensegrity application for some common practical purpose, but there is none I'm aware of. It's just so damn cool, I want tensegrity to be good for something beyond spheroid toys and Kenneth Snelson towers. I doubt a tensegrity stucture would really be useful for a tonearm, but I have wondered whether it may be helpful as an isolation suspension device for components, maybe even TT's.
I have finally recieved the HIFI mod for my rb-300, and I have to say that evan though I had ideas of how it would sound, I am stunned.
First off, it is important for me to state that my system is lower in resolution than what I have been used to, and I have to state that it is more than likely lower in resolution than most of the systems that poeple would likely have that wanted to add these sidewieghts. I point the finger solely at the vanderstten 2ci's, while the are sweet sounding, and convey the music, and make the room sound quite good, they lack accuracy. I am not driving them with the best amp for them currently as well.
The reason this is important to say is because to get the 2ci's to stage, to pinpoint, (one of the inherent strenghts of vinal) and to play clean at the same time is more of an accomplishment to be able to hear with these speakers.
The other arm that I am using is an older model immedia. Comparisms are nessesary because frankly right now the immedia is a better arm. It conveys more detail and information. There is roughly twice the cymbal info, separates the midrange instruments better, offers an easier to define bass line.
But compared to the rb-300, the rb does something the immedia can't seem to get. It boogies. The bass is subjectively more involving, more of a tune. The voices of instruments seem to come out with more emotion. While a simple a-b between the two would reveal that to almost anyone, the immedia would be more accurate, and better, what the rb does is impossible to ignore. For me, the obvious goal is to make the rb as good as the immedia. At first, I would understand this to be to somehow make the rb convey the low-level detail of the immedia, stage as pinpoint, and be overall more accurate. Direct comparisms between the two would lead me to believe that most of this would happen in the upper frequencies. So a modification that would seem to take the arm in another direction might seem backwards.
At first, it did. upper midrange information seemed to be attenuated. The air that surrounds cymbals, and the vibrations that pop out and accompany certain voices and horns and lead instruments were the first casualties. But while some of this energy that I would initially seek went away, right at that same place was more depth. I was playing ELVIN!, a record in which Elvin jones is miked up front, with Art Davis on bass to the side and toward the back. This is a great recording for finding detail, as part of what makes it so exciting is Elvin's speed and energy on the kit, and the way it was recorded, there is an abundance of different sounds coming from the drums.
While some of the snap from Elvin quickly wacking the cymbals and rims was not as apparent, And Art didn't pop out onto the room quite the same as I have come to expect, Elvin's kit was also wider, and deeper. Art's bass also had what seemed to me another octave down. I couldn't decide which was better, and I knew I was in for more work in listening. this was going to be harder than I had expected, and it was time to pull out the records that I know like the back of my hand, dirty or not, and wear them evan more.
Next was Van's THE HEALING GAME. There is a track that has a lead bass and another playing the low. And on this record, there is a distinct decay that can be heard of the room when Van sings loud. This would surely tell me something. As I expected, There was more separation between the two basses, But what I actually didn't expect, is the definite lower octave of the second bass, that made comparisms betwwen the two moot. Van also, took up more width betwwen the speakers that before. this is curious. He is undoubtably miked in the center no matter which system it is played on, and to hear a voice take more width, that can easily be disterned is baffuling. At the same time, The back up vocalist, who repeats Van, was farther to the right and back, and more of a pinpoint, and smaller. On to another track, with an opening of an organ. The bass pedal of the organ was deeper. This is the stuff that makes me want to listen to the rb more than the immedia, but I still had questions about the detail and accuracy.
For me, this means getting out Cannonball PLUS, the origional issue. This is my most accurate recording. It starts out with Cannonball's horn which is followed by a natural echo that you can follow as the soundwaves travel acrass the room and SLAM into something and scatter. The bass is recorded up front, and the bass player actually speeds up in his exitement, and the drummer struggles at first to keep up. He seems to be hitting the cymbals harder to keep the pace, so there is cymbal sounds scattering all around.
What I heard here was definite. The bass was definitely deeper, there was another octave down that I have never heard before, except on occasion with my Theta. The air that seemed to be missing from the high frequency energy was shown as a resonence that when missing, revealed the cymbal playing, (which is quite loud and up-front on this record) to be the best I have heard on this record so far. Instead of splashing all around the upper left side, there was a cymbal being tossed side to side, that was definite and discernable as a cymbal being tossed as it is being wacked.
I played more records, but I'll sum up here for now. I was able to decrease the tracking force to 1.65 grams and regain some of the lost midband energy, with no buzzing or other audible mistracking. I was able to visualy dicern the slightest cantilever movement, both with the HIFI and without, but not enough to see at this time whether there was a difference, but it was both less than I have observed with other arms at times and within the accuracy that I usually set up the zenith. All records, in an a/b with and without the tweak had a change in staging, which was wider and more behind the speakers, and that is something that the vandy 2ci's have trouble with. The 2ci's don't pinpoint well, but the differences were audibly "visible" as far as distances before and after.
As for the lost energy in some of the frequencies in the upper and mids, I'm right now of the opinion that it could be replaced somewhere else, that would in the end be more accurate and detialed. I can't be sure whether the energy that is lost is from the start inaccurate in the first place, or whether it is revealing another fault in the arm that was not present before, or whether it is actually a side effect of the tweak. I am sure that it adds positve, more accurate effects, in the bass and in the staging qualities. It moves the overall performance farther away from the immedia, in the tonal presentation and the presentation in the mids, but closer in the pinpointing and staging, (something the damping effects in the immedia, hmmm), but the bass the immedia just can't do.
In the effort to get better sound, more accurate in some or all areas, rather than add to the qualities that are good it is more accurate to subtract those that are bad, evan as it initially seems to go in the opposite direction. In the end this is where transparencey and exitement is.
In my case, the HIFI stays.
And this is just the sound, what it is actually doing I am still with my origional guesses, that are posted above, but I have less doubt that the cantilever is moving in relation to the coils. It is not an issue anymore, as far as damage or evan having a negative effect on the sound, but what is still a guess for me is what it is really doing. The difference in horizontal mass and vertical mass, is still something I think may be something to pay more attention to.
I wonder if this is measuruble, definable and proveable, and I actually wonder what arm may possibly be as accurate in the bass as this. It has taken me a while to write this, and I have actually never heard a vinal playback system have such an accurate, full bass. It would take a direct comparism to know, with more than my humble system.
Its time to step up to the newest of grahams and immedias, the wheatons and such. It is past the older immedia and the rega's.
TWL, it looks like you are getting a little following here. As the opportunity has presented itself I have continued to listen to my TT and hearing better sound on familiar recordings.
I have an original Columbia six eye Dave Brubeck LP on right now. WOW! Detail I never heard before, air, soundstage, and bass. I want to glance over my shoulder and see the guy playing the horn. It sounds so real.
I had considered selling the RB 900 for a while, but as I hear it now, why would I want to sell???
Glad you guys are enjoying the mod. I emailed Basement and suggested a VTA change to restore the tonal balance. With the added authority of the bass info provided with the HiFi mod, it is concievable that a VTA change could be in order. I speculate that a slight rise in VTA will give him the mids and highs that he wants, and more detail will be shown there too. With his VTA previously adjusted for the tonal balance of the unmodded arm, this mod just may require that VTA adjustment. I needed to adjust mine also.

Nate, if you didn't notice as much bass improvement as you may have liked, you might try lowering your VTA a slight amount, and see how you like that.

I am very happy that this has been an improvement for both of you, as well as for myself. I think that this is absolutely a Kick-Ass mod.

I am looking into the packaging and marketing aspects of this right now.
Interestingly enough, I did have the vta adjusted like this for the second part of my listening. Before this, I was careful to match the vta to where the vta was on the immedia, which is usually about 1 millameter higher at the beginning of the record with the cartridge just before the lead out groove. While in readings it seems that that is unusually high, both me and my dealer found the same vta for the clavis seperately before we consulted each other. I found this true with the lydian as well. Every other cartridge I have used has been with the vta lower in the back.
That experience alone has made me pay attention to vta. While tonal balance can be affected, I don't adjust vta for it. I don't think that you have either, but right off I would think that the mod is allowing for a set up that is more orietated to extracting more detail, rather than subtracting it in the mod itself. As I have listened to it a little more, I have no indication that there is anything odd or incorrect in the tonal balance. Subjectively I would say it is more correct.
A freind of mine stopped by while I was playing a record, and he commented on how good the system is sounding. He hears my stereo often but he is a non-audiophile.
I am still in the direction that there is improvement to be had in the rb that is more revealed by this mod, rather than that it is just a trade off for the improvement in other areas. I have always thought that the rb sounded a little weird, somehow, in it's energy, and the reviews that I have read, all think it is a great arm but every reviewer, evan those of a glowing review, have something they hear that keeps them from putting it at the top of the best they ever heard, or what they believe is the best, etc.
And also, bear in mind the reputation for the tonal qualities of the immedia.
This is one of the most fun and promising mods I have done in a long time, my own or purchased, or tried from another's idea, maybe the best. I hope you get the credit you deserve, because you (twl) have brought me much enjoyment in the sound evan if I was to leave it at this.
But don't think I will.
Best of luck, Twl, with whatever venture you may undertake to market your idea - have you sought patent advice? I'm just sorry that I can't try it out for myself, as I would love to be able to test this on my own ears. Well, I returned Saturday from a brief out-of-town excursion, and as usual, I came home laden with scrounged vinyl, so at least I have something to console myself with!
It is truly a shame that this tweaek did not take off. The cost is virtually nothing and the benefits are huge. There is nothing a person could do to their turntable or arm that will is this cheap and sounds this much better. A person could spend hundreds of dollars on a better arm that would not be as much of an improvement.
TWL should be in line for the tweak of the year award. This is a product that should have been incorporated in better arms for years. Why it has not been done before is anyone's guess, but it should be done now.
The improvement is not subtle, it makes a dramatic differerence.
Anyone who has a pivoting tonearm needs to have this. Even if a person is not handy! This is easy to do, and worth the minimal cost.
WOW! WOW!! WOW!!! WOW!!!! WOW!!!!! WOW!!!!!! WOW!!!!!!!
God Bless Tom W. Lyons "esquire"
Thank you so much Tom, It’s as if some one has remastered my Record collection.
Nrchy, it appears momentum may yet be building slowly... :-) Twl, with Roni on board, what is the grand total of beta-adopters?
Tom:

I have kept returning to this thread with interest over the months, and while the market for you to go full retail may still be evasive, I would like to jump into the water as a paying customer.

As I've mentioned in other threads, I have an RB-600 and am currently running a Dynavector 20xh cart. Can you email me directly with purchase price for your HIFI mod and any installation hints, as well as any setup adjustments you'd recommend based on my current cartridge?

Thanks!

Tim
Hi Tom, Im back in the game. Whenever you have time, lets discuss feasobility of the beta-mod on my ancient rig {Pluto audio 6A Special arm (plutoaudio.nl) / S Yorke S4 / Clearaudio Insider -- stiff}.
Tom, can you share, in a general sense, the types of arms on which this mod can and cannot be implemented?
Sure David. This mod was originally designed for the OL Silver tonearm, and can just as easily be applied to any Rega tonearm. There may be others that could benefit, but I haven't actually tried any others. The key factor is that they must have a bearing yoke arrangement where the weights can be attached to the bearing axle locations without interfering with anything else in the mechanism. Some arms have an enclosure or housing surrounding the bearing yokes, and this is something that would preclude the use of this mod. The Rega and OL Silver arms have very open architecture in this area, and are easy to mod with these weights. At this time, I have not tried to use this on any unipivot arms, and I am hesitant to recommend its use for unipivots, because generally the result would have negative results on the vertical behavior of the arm. It is critical for this mod to be directly concentric with the bearing axle that controls vertical movement, so that it has no effect in that plane of motion. With a unipivot, that location is very difficult to achieve.
I wanted to respond to Basements post of 10-06-02
First of all thank you for your post, a lot of thought and work went into it.
You seem to ask a question about arm movement and cantilever movement.
As Tom stated in his original post, with a low compliance cartridge like a 501,the one we both use, this demands a lot from a tonearm. The lower frequencies are always harder to reproduce because this energy is most times so difficult for the cartridge to trace. The bass energy moves the arm not the cantilever.

With the Hi FI mod you can now hear so much more bass information it is scary. This proves Toms theory that the arm is working better. The loss of those high end frequencies is I believe as you stated, really a loss of distortion, because everything is so much clearer,has more detail, more information.

I just wanted to add that I have in the past had trouble setting my VTA. This is a thing of the past, with the arm working so well it is now very easy for me to hear where the vta is best. I now have two settings, one for 180-200 grams and one for the rest.

This is another reason I like the Origin Live Aurora Table with its open design it only takes me 10 seconds to make a VTA adjustment.

Origin live states you should not tighten the base nut of the Silver Tonearm to tightly because it deadens the sound this is also much easier to hear now.

Thanks again Tom, this is truly a mod for the ages. We all struggle to improve our systems, new amps, speakers, wire cryo, you name it, but this mod does so much to improve the sound. One cannot over state it's significance. I have not heard a Rockport or Walker, but NOW, I think I now know how they sound, really its that good. I know I can improve my system more, and when I do, it will not be as dramatic as this mod, but I hope and pray that it is.
I'm real happy that you like the mod, Ron. Thanks for your great descriptions about the sonic improvements. I've even been getting some more interest from others in the HiFi mod now. Maybe it will actually "catch on" after all. I just like to improve my system, and thought others would like the nice benefits of something I figured out. Everybody seems to have the same reaction. Usually they just say, "WOW!", like you did earlier.
Hi Tom
I was reading all the responses to your tweak and got a stiff neck! I don't have the technical mastery of theoretical parameters of the tonearm's design. I have a very good intuitive understanding of the fundamental physics that are involved in a correct design, one that employs natural principles to it's function. This is the reason that I regard the frictionless "Schroeder" type of arm to be the most natural sounding which also implies that it must be the most musical sounding. The German reviewer said so when he compared it with the SME and other top quality arms. It didn't have the best base,(which is understandable given it's design) even though all the information was there, but in the concert hall, one does not hear "base" standing out, but a seamless wall of sound.
I have designed one such tonearm but I am stuck in the technical aspects of how much strength the magnets that stabilize the arm should have, so that it's inertia relative to it's mass, is not excessive. This of course can be achieved by increasing the magnet's gap so that their strength is decreased making the lateral motion easier.
What I am asking is, if there is a formula that can be understood by a layman, to calculate how strong the resistance of the arm should be in proportion to it's mass. In other words, what is their ideal ratio?
Thanks in advance!
Ted
Ted, the needed lateral mass is relative to the compliance of the cartridge suspension. The lower the compliance(stiffer), the more lateral mass is needed for proper stabilization of the arm.
Low inertia is needed in the vertical plane so as to track warped records. But many records don't have the spindle hole placed exactly right, so there is some side-to-side arm motion, similar to warp but in the other plane. Your arm modification would make that problem worse.
Eldartford, any spindle centering problems cause quite slow moving variations in the tracking of the groove by the tonearm. This mod handles that with no trouble whatever. Any relatively slow movement of the arm in a side-to-side direction, can easily be managed, and are managed by a tonearm with this mod. A record with even 1/8" off-center hole punch will only vary by 1/4" over a full rotation, and it is spread out over the whole rotation. This is nothing that would cause a modded arm to have any trouble. The arm moves with the groove as it tracks toward the center of the record quite accurately, manages off-center records as well as that arm ever did without the mod, and makes sound better. I'd consider that a successful result. If the arm has a wildly off-center hole punch, I'd consider that a defective record, and I don't design my arms to handle defective records, to the detriment of their ability to play normal records better. You could also say that if a record has a warp like a potato chip, then an arm wouldn't handle it, but is that the fault of the record or the arm? Even so, my modded arm tracks off-center records like a champ.
I should be working instead of spending time here, but I can't help myself. Besides, I have had a lot of benifit and fun from the interest this thread has spurned, so I feel I should put in another 2 cents.
Thank you Mr. Rockonroni for mentioning your appreciation. Your description of how it effects how you can easier identify mistracting and setup is insightful. It is helpful that you mention such because besides the obvious advantage of being able to set up better, it is an indication that what is lost are likely distortions, and what is gained is likely more accurate. I should mention that my experience in that area mirrors yours; mistracting errors seem to be easier to identify for what they are, they seem to 'stick out' more obviously.
I think it worth mentioning that although I have not wieghed it, the mass the HIFI adds is closer to the immedia than without, (I say I haven't wieghed it but it is obvious enough it is not nessesary to know that), so the only issue would be the correlation between mass and sonic benifit, not any danger of excess wear or damage (or not functiong or tracking properly).
Furthermore, the sample I got (the only one I have used) came reamed out to fit one the ends, but not with any glue, and I fastened it by pressing it on, and did not use anything to help hold them. They fit pretty darn good at first, but one would occasionally fall off. As this continued they fit less secure. I then put more effort into 'cramming' them on and I noticed the sound improved. Perhaps there is a correlation with the fact that they are lead and right at the bearing, having some sort of damping effect, similar to other mods that have been succesful on rega's.