The pivoted arm experiment is over


I started the thread titled "are linear tracking arms better than pivoted arms" and as a result of the many thought provoking threads that were posted, I decided to revisit pivoted arms again.

First of all, I want to say thanks to Dertonarm for starting me on this journey and all of the help he gave me in setting up my arm. As some of you recall, I purchased a Fidelity Research FR64s, a NOS Orsonic headshell, and an AQ LeoPard tonearm cable. This was all mounted on a new armboard on my VPI TNT table. After I had removed the ET-2 from the TNT and while I was waiting for the new arm and all of the other parts to arrive, I went ahead and did some maintenance to the TNT. I removed the bearing assembly and took it to a machinist for inspection. He didn't like the fact that there was .004 clearance between the spindle and bushing. He pressed out the old bushings, machined new ones, line bored them, and pressed them in. There is now .001 clearance between the spindle and the new bushings. The machinist also micro polished the spindle, cleaned all of the remaining parts, put in new oil, and declared it finished. Dertonarm was emphatic that I install the FR64s 231.5 mm from the spindle to the center of the bearing instead of 230mm as the manual recommends (as well as the template FR provide with the arm. The machinist made a tool from barstock that fits over the spindle of the TNT and has a hole drilled at the other end with the center at exactly 231.5mm. He machined a tramel point that fits in the hole so you can mark the armboard with the exact spot for the correct distance. This tool was used on my new armboard and the hole was precisely drilled for the FR64s. I used the Dennesen Soundtracker to set up the cartridge as recommended by Dertonarm and VTF was set using a digital scale. I have the SDS for my TNT and speed was checked and set using the KAB strobe. I am telling you all of this so that you understand that I went through great pains to install this arm correctly. The cartridge I used during this time was my almost new Benz Glider SL.

I found the FR64s much more difficult/time consuming to set up compared to other pivoted arms I have used over the years. Some of you may disagree, but this is my experience. Most pivoted arms, once you have the cartridge installed, you slide on the main counterweight, make sure the anti-skating is set to zero, move the counterweight until the arm floats level, set the counterweight scale to 0, and then turn it until you have the correct VTF and bingo-Jed's a millionaire. Then you set your anti-skating for whatever makes your socks roll up and down, and your pretty much done. After that you just start dialing your cartridge alignment in with your favorite alignment jig and readjust your VTF. Not so with the FR64s. The FR64s has a main counterweight, a dynamic stabilizer weight, and an anti-skating weight that all must be installed. I am not going to go through all of the necessary steps to get this arm set up, but trust me, if you have never set up a FR64s, it is more difficult than your average pivoted arm that I am used to. Again thanks to Dertonarm for all of the help during this process and Syntax offered some help to me as well which I also appreciate.

Before I removed the ET-2 I broke out a NOS Maxell UD 35-180 tape (I love this tape by the way). I recorded a selection of songs (at 15 ips 2 track on my Otari MX-55)that would showcase the FR64s arm's ability to boogie in the bass as well as track the many dynamic swings that many of these cuts have. I recorded the following songs:

Lyle Lovett-My baby don't tolerate
Lucinda Williams-Righteously
Herb Alpert-Rotation (from the MoFi version)
Talking Heads-Burning down the house
Herbie Hancock-Rocket (from the 12" single)

After I had the FR64s installed for about a week and had it as tweaked out as I knew how to make it, I re-recorded the above selections in reverse order on the same tape. That way at least I had one cut that would play back to back.

Now some of you had sent me emails asking if I had any preliminary findings to share and I demurred. I never claimed to have the fastest ears in the west so I like to take my time and make sure I know what I am talking about so I don't have to eat a plateful of crow later (which I have certainly done before). Well, the jury is in for me, and it is my opinion that the ET-2 is much the better arm. The only thing the ET-2 gives up to the FR64s is a bit of bass punch, but I don't think the bass from the 64s sounds as natural as that from the ET-2. The bass from the 64s almost seems detached from the rest of the music if that makes any sense. There is a myth that linear tracking arms don't have good bass or can't reproduce the bottom octave at all. This is nonsense in my opinion. I can speak for the ET-2 and tell you confidently that it reproduce great bass.

MikeL and I sort of got into an off-topic discussion on the TP forum. MikeL stated (and please correct me if I not capturing the essence of what you said Mike) that he thought his Rockport linear tracking arm was superior to pivoted arms because it tracks the grooves the way they were cut and that as a result, it doesn't have any phase errors. MikeL went on to say that all pivoted arms only have two null points where the geometry is correct and that results in phase errors across the remaining points outside of the null. I didn't agree with Mike's point about phase-I thought Mike was confusing zenith with overhang. Incorrect zenith will affect phase, but I certainly had never heard that pivoted arms caused phase problems across the record except for the null points. What Mike did say and I agree with is that you can tell a big difference between linear tracking arms and pivoted arms. For me, a properly set up linear tracking arm sounds like a master tape with all that implies vice sounding like a good recording. There is a "wholeness" about the sound of linear tracking arms. Music just flows like it does in real life and it feels right. The FR64s and other pivoted arms don't capture that. They almost seem like they are stitching the music together as they go-almost digital like in comparison to linear tracking arms if that makes any sense to you. Another apt comarison would be looking at a picture taken by a cheap digital camera and comparing that picture to one taken from a top-notch film camera. You really can't compare the two in terms of ultimate sound quality as the linear tracking arm is just cut from a different cloth. I know that will set some people's teeth on edge, but sorry, the truth is the truth. I really do think the secret is the fact that the linear tracking arm is tracing the record the way it was cut instead of tracing an arc across the record with incorrect geometry 99% of the time. You can argue that the errors are slight when using 10" and longer tonearms, but errors they are. Also, the other benefit to linear tracking arms in my mind is no anti-skating is required. That is one less thing to fiddle with and neurose over. The sound of music from a linear tracking arm lives and breathes in a way that music does in real life and it is all cut from the same cloth. Pivoted arms that I have heard can't capture that. Unless you have heard a good linear tracking arm in your system, you won't know what I am talking about and you can be happy with what you have.

In closing, I know that the FR64s is not the most expensive pivoted arm in the world and some of you may sniff your upturned nose and say I should have used a "better" arm. I am really not going to listen to any of that drivel. I spent around $3K setting up this experiment and I know that the FR64s is considered a damn fine tonearm which is why I bought it. I am also finished with discussions about linear tracking arms being harder on cartridges and they can't have great bass. I had many years of great service with my Van den Hul MC-10 in an ET-2. My Denon 103R did develop a slight twist in the cantilever, but that may or may not have been caused by the ET-2. You are supposed to use high compliance cartridges with the ET-2 and not low compliance cartridges like the Denon 103R. The Benz Glider is a much better match with the ET-2 and it sounds way better than the 103R. Even if it is true that linear tracking arms cause greater wear to the cartridge suspension-so what? Most audiophiles change their cartridges more frequently than they change their underwear and they would never know. MikeL has the same experience that I had and that is he saw no wear over years with his Van den Hul. But even if it is true that linear tracking arms cause greater wear and tear to a cartridge, that is a small price to pay for the superior sound over the life of the cartridge.

I reinstalled my ET-2 last night and I haven't stopped grinning since. There is no doubt that if I would have made the recording of the ET-2 with the bearing improvements to my TNT, it would sound even better than it does. My LP setup has never sounded better now that my TNT bearing has been massaged and the ET-2 is back. I stayed up until way-late o'clock last night because I just didn't want to stop listening to music. Over and out.
mepearson
Hi Mepearson,

Any time you're interested, contact me offline. I suspect that you have found an arm in the ET-2 that floats your boat in ways that others cannot.

It would be a difficult (impossible) experiment to carry out - to produce a pivoted arm with identical sonics (with a given cartridge) to the ET-2 - save of course the inherrent characteristics of the geometry.

If this were possible, I suspect that this would become your #2 choice in arms.

For those of you who have not done so, download the two part ET-2 tonearm manual (PDF). It's in old-timey font, from the good old daze and in two parts from back when bandwidth was much more limited than it is today.

The manual is chock full of great information on tonearms in general, and of course with specific information on the ET-2.

You'll not only understand your own tonearm better, but will gain insight into the genius behind the ET-2 arm.

Cheers,
Thom @ Galibier

I think the kind of phase distortion MikeL talked about has to do with "angular misalignment will mean that one channel of the stereo signal will be played fractionally before the other – adding phase distortion?" The quote is from a TNT Audio review of the new SME 12 inch arm.

I never thought of it that way but it makes sense.

.
Been reading this topic and just wondered if there is a minimum quality level of turntable one should have before considering a linear tracking tonearm for future reference. Currently, my analog front end is a Rega P3-24 with standard RB 301 arm and a Benz MC Gold Cartridge.
Anything that is good for a high quality arm should do fine. It should not matter whether the arm is straight or radial tracking.
I would only add that(in theory at least) the TT should not be so lightly sprung that the moving horizontal mass of the LT affects level of carriage.
Sorry to chime in so late to this interesting discussion, but I want to share my experience with linear arms vs a Fidelity Research arm.

I am currently using a Fidelity Research Fr 66S/Orsonic headshell/Ikeda silver headshell wire with a Koetsu Coralstone on a Technics sp 10 Mk III. The cartridge was set up and adjusted with a Mint LP protractor custom made for this turntable and arm set up.

I have owned both the Walker Black Diamond and Kuzma Airline Arm, both of which are inspired designs with extraordinary performance, and which I could easily live happily ever after with. I could talk about the relative merits of each but that would distract.

We are in consensus that equipment compatibility and personal taste have an influence on all tests and as such any comments are ones personal opinion.

Before acquiring the FR 66s, I was looking for a high mass tone arm to control and manage the cartridge in order to bring out the best from low compliance cartridges, like Koetsu. In general we all know they have a wonderful midrange, but a reputation for a sloppy less than stellar bass control. Since I plan to always have at least one Koetsu in my inventory of cartridges to listen and enjoy, I landed on the FR 66s.

From the first listening session, I realized I was on to something special. I went through 3 headshells before finding the Orsonic for this cartridge.
IMO and in my system they are a perfect marriage. All the weaknesses were
minimized or eliminated. The bass is powerful and controlled, something I was unable to achieve with the linear trackers. The dynamics
greatly eclipsed any linear tracker i experienced in the past. Micro detail and high frequency extension virtually matched the linear trackers. This is the one area that was a real horse race, too close to call. And for tractability, I would rate them super close again. The air around the instruments may be a touch better with the linear trackers, but not an overwhelming difference.

I can not comment on the wonderful review between the ET and the 64s, because there are so many factors that could influence the test. With my system, I am pleased with the Fidelity Research performance and recommend it.
.
Logenn: "I can not comment on the wonderful review between the ET and the 64s, because there are so many factors that could influence the test."

Thanks for the nice description and review of the FR-66s. I just want to point out that the FR-66s is a 12 inch tonearm and whereas the FR-64 is a 9 incher. I understand Mepearson has reached a conclusion in his experiment that he prefers the ET linear tracker and I would assume this is due to the superior (geometric) tracking over a 9 inch pivot arm. But what happens when the ET is compared to a 12 incher? The conclusion might be different, I suspect. I think a three way comparison will give a better understanding by having a linear arm, a 9 inch arm, and a 12 inch arm.

______
Hiho,

Actually the FR64s is a 10inch arm (245mm effective length). Ikeda-san himself has a writeup that says anything less than 10" is not favoured by him. And I agree that the 12" arm and the FR66s would have reduced tracking distrotions compared to the FR64s. And in the context of a low compliance cartridge like the Koetsu, the 12" FR66s with its higher mass is actually a better match than the FR64s.
For me, the thing about Logenn's review is that it highlights the importance of matching the cartridge and tonearm. The FR64s and FR66s are a wonderful match for the low compliance Koetsu, Ortfon SPU, Denon DL103 and Ikeda/FR cartridges. In the original review of Mepearson, he matched the Benz Glider SL with the FR64s and compares it to the ET-2. With the Benz Glider, the ET-2 arm is a better match than the FR64s and to me, that's going to account for the most significant difference in sound between the 2 arms. But if you put a Koetsu or SPU cartridge on the ET-2, then it would not be a good match for it and unfair to comapre it then with a FR64s/66s. So again, for me, there is a limitation of being able to compare the ET-2 and the FR64/66s since they have such a big differnece in mass and matching ideal cartridges. For me, if we wanted to compare a linear tracker like the ET-2 to a pivoted arm, we should try to find arms that would match well with a common cartrigde and so for example comparison between a Graham or Triplanar, using the Benz Glider would be more ideal. FWIW.
Logenn, Hiho, Ken Sugano always favored the Fidelity Research FR-64/66s tonearms for his own cartridges when asked back in the early 1980ies. The FR-64s is rather a 10" pivot tonearm. This is just for the books.
Ddriveman is correct.

The key issue here is for Mepearson's test to be valid he should look to revise his testing by either substituting a different higher mass cartridge, Denon 103 for example, or changing the weight of the headshell on the 64s (18 g), to perhaps a lighter one, Yamamoto tsuge wood headshell (7.5g).

Since I have no experience with the Benz, this second idea needs to be researched to determine if the change makes the setup more compatible. You have eliminated almost 10 g which could make a difference.
Dear Logenn: He already sold it, at least I saw it in Agon ads.

Regards and enjoy the music,
Raul.
Mepearson wanted to test the FR-64s against the ET2 with as many parameters stable as possible. Thus his test was a valid one. Furthermore - in the most complete test the FR-64s ever got by any audio magazine (09/1980 German HiFi-Exklusiv), the FR-64s was tested for the books with a Shure V15 III to illustrate its low bearing friction. Despite the fact that this was far away from an ideal match in terms of resonance frequency, the Shure was able to show its maximum trackability with the lowest VTF ever in the FR-64s. A very good test by the way to illustrate bearing friction in a pivot tonearm.
So the FR-64s should be working with a Benz Glider too.
Today we have very few cartridges which actually do have a compliance lower than 10xdyne. All top-flight cartridges on the market today do feature a compliance of 10xdyne +. Same for all Koetsu - except for the older Matsushita made original Koetsu Black of the late 1980ies.
Resonance frequency is one thing - but not all important. Energy transfer (if little noticed by the majority of writers ) and inner balance (which the FR-64s has, thanks to his lateral balance option which almost eliminates the skating-force where it initiates ) too are - in my humble opinion - key features of a pivot tonearm addressing most of the design's issues.
Dear DT, My Dynavector DV505 has the lateral balance weight, too. And after I became familiar with it, I began to notice that this was a feature on many of the best Japanese tonearms of the 80s and 90s. However, that feature seems to have vanished entirely from the design of even the most expensive pivoted tonearms these days, including the Dynavector DV507 and the MkII version. Why do you think this is the case?

And I must admit I am not sure how to use it correctly; I set it so that the arm is stable in the lateral plane, when VTF =0 and anti-skate is OFF. This mandated bringing the lateral balance weight in as close as possible to the main vertical shaft. I am not sure that makes sense. The English translation of the DV505 instruction manual leaves something to be desired in terms of clarity. Have I used the correct method? Thanks.
Dear Lewm, correct applied lateral balance means the tonearm will stand "still" at any point of the arc over the record. This of course in the state of zero balance (= O VTF and O antiskating) only millimeters above the record surface and horizontal full balanced (= parallel to surface). Full balanced with mounted cartridge. If so - and if the tonearm indeed won't move neither inward nor outward from any set position, it is in optimal lateral balance now. Which in turn mean that the skating force initialized by the offset angle in a pivot design (save for those 2 or 3 designs following the Thales-principle) in now nullified at the bearing. Consequently the needed antiskating is now very little (ideal it now will be almost zero - which it is with the FR-66s for instance).
So in any pivot tonearm offering the option of lateral balance, the task is to bring the tonearm into a state of true balance unaffected any more by any off-set angle in the cartridge-mounting/headshell.
By doing so you minimize any needed antiskating force.

Yes, you are right, lateral balance was standard with the most of the top-flight Japanese tonearms of the 1970ies and 1980ies. But this is only one of a few well proven design features of pivot tonearm design which got somehow forgotten along the way of high-end evolution during the past 2 decades.
It has some advantages if a mechanical design has some graduated engineers among its parents.
I did some web searching since posting my question. It seems that the lateral balance weight is mostly made necessary by the S-shaped or J-shaped arm tubes prevalent on the vintage Japanese tonearms, because such shapes put most of the tonearm mass to the right or to the outside of a line drawn from the stylus tip to the pivot. With a straight pipe, the lateral balance weight is less of a necessity, although it would still be of some use due to the offset angle at the headshell. There were several opinions regarding how to set the balance weight. The most common method appears to be to lift the rear of the tt by a small amount and then set the balance weight so the tonearm (set for 0 VTF and 0 anti-skate and "floating") does not shift position during this maneuver. For the Dynavector, I am not sure this would work well, because of the magnetic arm rest which would prevent free motion whilst lifting the rear of the table. Moreover, the DV505 manual says nothing about lifting the tt. I'll figure it out.
Lewm,

Actually, for lateral weight adjustments, you are suppose to tilt the turntable backwards i.e. lift the front of the turntable. This would avoid interfering with the arm rest. This is explained in the FR64/66 manual. If the turntable is very heavy and difficult to lift, you can set the balance weight such that the arm is tilted slightly backwards and with antiskate set to zero see, if the arm will stay in position when place in the middle of the platter, This was taught to me by Tommy Cheuk of Topclass Audio.
I tend to agree with you the J or S shape tonearms seem to be more sensitive to lateral balance. I have a Micro Seiki MAX237/282 tonearm with several armwands. The J shaped armwand seem to be more senstive and in fact Micro Seiki recommends adding more antiskate when using it in place of the straight armwand. Hope this helps.
Lewm, Ddriveman, while I too have bought some items from Tommy of TCA, this advise lifting the turntable is not a great one.
The cueing cylinder of the FR-tonearms can be height-adjusted in a few seconds.
The FR-60-series manual - BTW - contains some mistakes.
This is not the only one.
Lifting the turntable to ease the procedure is plain... - well, you guess what I want to say.
A J- or S- shaped pivot tonearm is designed to accommodate a straight headshell.
It is still the off-set angle - being a larger one or a smaller one.. (J- or S- shapeand 9", 10" or 12") - we are talking about.
Dertonarm,

If lifting the TT is wrong as shown in the FR64/66 manual, then what would you suggest please.
Ddriveman, I can not see any negative point in adjusting zero full balance while the TT is dead level. If one tries to adjust any static or dynamic balanced mode for a tonearm on any given TT, I would always recommend to do this with all other parameters stable. If the lateral balance adjustment is performed with the TT in place and level, you can be sure that the result of the adjustment is not a by-product of some other static mode which took place only for a brief moment while adjusting (i.e. lifting the TT).
BTW - I can't see any advantage of the "lift the TT"-method.
Besides that, it would be a though act to follow with a handful of serious TTs out there (Continuum, MS 3000/5000/8000, Rockport, Apolyt (BTW - there is a 13 year old used Apolyt for sale on ebay-Germany right now - 2 days left and over EURO 12k already (no - it is not me selling it..) Verdier etc.
The adjustment of lateral balance is easy to do as described earlier. The cueing cylinder on the FR-60-series tonearms can be adjusted in heights so the arm rest/cueing rest won't interfere with horizontal balance.
The antiskating device can be either dismounted for a few minutes or disengaged while adjusting lateral balance.
So there really isn't any point to alter the level of the TT while bringing the tonearm in full lateral balance.
Ddriveman, It is interesting that you learned to lift the front of the table. I did find some old posts on Vinyl Asylum recommending the same strategy. But the majority were for lifting the rear. When I thought about it, lifting the front end would cause the tonearm, with or without a lateral balance weight, to want to swing around all the way to the rear extreme of its arc. That did not seem like a good idea. However, I certainly am not trying to contradict you, if it worked for you.

DT, Headshell or no headshell, an S- or J-shaped arm tube still has most of its mass well to one side of the straight line between stylus and pivot, whereas a straight pipe, most popular these days, will be less extremely displaced to one side of that line. This was my only point. But, like Ddriveman, I am interested to learn of another way to set the lateral balance that does not involve lifting one end or the other of the turntable, which is an idea I do not like either.
Lewm, of course, but that is not the problem - as long as I have the option to nullify this off-set by setting a lateral balance.
Whereas on a many of todays "straight" pivot tonearms with "small mass displacement" at the cartridge mounting headshell-part only, a lateral balance option is missing and one has to mess around with antiskating compensation.
If we can tame the beast at the source - why missing the chance ?
Der,

How do you remove/disengage the AS on the FR66s? Do i just remove the screw and pull it off?
Dertonarm, Lewm

I too agree that lifting of tt is not prefereble and for me, I cannot even lift my Galibier Gavis TT since it is almost 100lbs. But I was referring to the FR64/66 manual which recommends lifting the front of the TT to check for lateral balance (after setting the level balance and with Zero VTF and zero antiskate). It seems from the FR manual that in order to check for lateral balance, one has to create a situation whereby the arm, which is in zero balance when level, is then put into a positive/negative balance to check if it swings.
Ddriveman, the FR-60-series manual has a lot of mistakes.
There are geometrical mistakes as well - not just this hilarious advise with the lifting of the turntable.
If there is a skating force due to offset from pivot/stylus line, then this will show on horizontal level as good.

Genesis168, you can either dismount the whole antiskating device by removing the central screw which bolts it to the armshaft (this is the smart way) while performing the lateral balance adjustment, or you just support the device till it is without contact to the arm (w/a matchbox or similar) - this is the fast and simple approach.
Both work just fine and allow lateral adjustment without any unwanted "by-force".
Thanks, guys. The thought of trying to lift any one of my at least 70-lb tts from the rear whilst standing at the front and also playing with the lateral balance weight was not a happy one. I did adjust the lateral balance of the DV505 with the table level, as per DT's suggestion, so I guess I will leave well enough alone.

DT, I by no means meant to imply that the lateral balance weight is not needed with a straight-pipe tonearm, I just meant that the need for it is a bit less than when using an S-shaped or J-shaped arm tube. This must have given license to eliminate it entirely, for good or ill. Or at least that is my only explanation for why it has been omitted in the modern era of tonearms.
Lewm, honestly, I believe that the lateral balance was kind of "forgotten" in most of today's designs.
Or "disposed"/"omitted" for "lack of importance" and "increase of complexity and cost". It is a smart and elegant option to eliminate a design inherent issue of pivot design right at the source. In the these areas we are talking about minor improvements in high-end audio reproduction. To ignore a design feature which unquestionable has only positive effects to the performance of a pivot tonearm and thus to the sonic performance of the cart/arm combination is hard to understand.
But maybe I am just missing the inherent sonic benefits of skating force.
Very late to this thread .. I've had a go at setting my FR64S (on a TD124) at 231.5 and I like what I'm hearing.

What I'm wondering is the correct arm interface to stylus tip distange for this arrangement ... I have things set at SPU distance (52mm) but wonder if I should drop to the standard 50mm or less? Not sure quite what I should be aiming for?
Excuse me for the mistakes that I make here, but, if the cutter is a linear tracker, isn't it driven by a motor, and although it might introduce more problems than it solves, wouldn't a motor-driven(close to the speed of the motor of the cutter) linear tracker be best(theoretically)?
... wouldn't a motor-driven(close to the speed of the motor of the cutter) linear tracker be best(theoretically)?
On most records, the cutting engineer varies the cutting head's motor speed as it move across the master. Grooves with low dynamic range are spaced tightly together, which allows more music per side. Grooves with greater dynamic range must be spaced farther apart, to prevent crosstalk or even groovewall penetration on dynamic peaks.

The only way a playback headshell "knows" the speed of an inward spiralling groove is to follow it. A motor driven playback headshell would inevitably fall behind the groove at some point and push ahead of it at others.

This could only be prevented by some sort of "look ahead" technology and a complex controller to alter the motor speed based on what's coming next, on a groove-by-groove basis. Good luck getting anyone to build that!
After reading half of the earlier thread on linear vs. pivoted arms (and being annoyed by the reiteration of wrong and mixed up technical arguments) I want to chime in with some notes.
- "stress" on the cantilever (by linear arms): If you want no deflection of the cantilever, there will be no signal. Most radical practical approach: Use a tiny carbon string glued to a straw, with a very low compliance cartridge that is light, like a beginning of 80's Coral. Or use an Infinity Black Widow arm. Obviously this want give ou much bass below 50Hz.
Otherwise you *choose* deflection along what you find "optimal". Deflection means that the arm moves not in-phase with the cartridge. This is not a bug but *the feature* that produces a signal from the cartridge. The most (and optimally "linear") LF output of a cartridge comes from a perfectly flat, centered LP ( :-) and an arm of infinite mass.
Between these poles, the optimization takes place.
- What is optimal? If we end up tracking the excentricity of the record because of infinite mass and imperfect LPs, it's obviously not optimal - this *real* stress on the cartridge does not produce a musical output of the cartridge, it's just subsonic junk, no master tape has useful musical information below 1Hz. On the other hand we don't want to compromise the tracking of LF musical signals by too low mass, and this extends to phase in the bass too, ie. we need a certain excess LF extension below actual musical notes and subsonic room noise and cues. I assume that there is musical information, mono, on tapes right down to (below) 10Hz. Musically seen, we should keep away from (and stay lower than) 10 Hz. This is not orthodox - but consequent and well thought through. The optimal cut-off/ resonance frequency leads IMO to frequencies in equal interval distance from 0.55 (LP) / 0.75 (EP) Hz and these 10 Hz. This results in an optimal *horizontal* resonance frequency around 2-3Hz (=SQR(0.55 * 10).
- Actually with a useful tool (sadly missing at that time) we could adapt any LP for optimally correct centering, and almost no 0.55Hz wobble, which fucks up music "even" on radial arms BTW.
- Vertical warps have a considerably higher frequency, just watch the cartridge from the side... It's usually double the frequency or more, up to 5-7 Hz. These signals should be filtered out by low enough vertical mass / resonance frequency. Doing the same calculation as before, we should know the LF cut-off of *vertical* signals: These are the out-of-phase signals in the bass. Any useful LP must try to keep at least the amplitude of these signals extremely low, because cartridges have an extremely hard time to track such signals. Usually the out-of-phase signal is high pass filtered below 100 Hz, and below 20Hz there isn't anything useful to be reproduced in a normal room anyway, as it's off-phase, will be cancelled, messes up cartridge tracking and consumes amplifier power with no purpose.
So we end up practically (in the safety zone IMO) with "between 7 and 20Hz", ie. ca. 12Hz *vertically*, preferably even higher. And maybe in this case a bit damping could be desirable.
- The "stress on the cantilever" is mostly dependent on horizontal resonance frequency, which is linked to horizontal mass & compliance . And bearing friction (practically non existing in an air bearing) and wire stiffness.
- It's interesting that one of the very best radial tonearms, the Moerch DP-8 "mimics" properties of a well set up air bearing arm: Very high horizontal mass with average vertical mass. :-) :-) :-)
- Problems of linear arms:
Wire stiffness - no lever advantage here. Wrong setup, changing lateral setup with VTA. In my ET 2.5 this is a problem. The thing that suffers most is... the bass. Very audible differences here with careful setup!
Subchassis movement: A subchassis (if desirable at all :-) should swing in the rotational plane quite lower than 2Hz... I don't know of any, and it would be problematic too. Wit the usual air-bearing arms (placed tangentially) the subchassis movement will be tracked by the cartridge, as will be any lateral acceleration of a turntable (seen from cartridge into the arm).
A linear arm has much less sensitivity to this, because the lateral forces cancel to a major degree, dynamically. But instead of forces on the cartridge you get forces on the bearing. These are audible too.
- Problems of radial arms: The cantilever pulls off-line of the tonearm axis, creating a skating force. This varies with musical signal, the tracked place on the record (radius), and surface properties which change more than we might expect. These *dynamic* skating forces constantly energize the horizontal resonance of cartridge/arm and modulate the musical signal. And the amount is dependent on the magnitude of the offset angle, giving a considerable advantage (here) with longer arms - or other more unorthodox approaches, like the Thales arms or similar.
BTW the same happens in the vertical plane with a "correct" vertical bearing placed exactly at the height of the LP tracking plane...
- In the end a well set up linear arm (not complicated, but still not often attained) has potentially a more stable tracking of LF musical signals.
- It's a complex trade-off! Setup is very important, and careful listening too. And better not based on wrong or semi-wrong theories, as much "expert" bandwidth as they take.
- Thanks Mepearson!
PS: I *like* to listen to music on a well set up vinyl rig... And yes, the proof is in the listening.
Mepearson....just for the heck of it, although a pain in the behind is to try your pivoted arm again, but without a/s. When I compared, I found that no a/s sounded better. I know that's heresy, but because your ET doesn't use it, a fair test is to try the FR with none.
Stringreen, To add to your argument Dertonarm mentioned
already in his previous post this 'lateral balance' which
also reduces the need for the anti-skate. To adjust this
balance one should balance the arm (without a/s)just bellow
the 0 g and move the l. weight till the arm is in equilibrium
at different positions on the radius. If I remember well J. Carr
removed the anti-skate as well the lift from his FR-64S in order
to get better results.

The results of the experiment do not surprise me. I have a tnt with a 12 inch jmw and then acquired an old beat up hw19 with an et. I found myself listening to the hw19 more and more until I broke down and sold the jmw and bought 2 more et's. I also pocketed a grand in the process. The only area the jmw was better was the depth of bass. However the et was not lacking and was more natural. It did take me a few weeks to optimize the new et on the tnt but now it is quite a bit better than the et hw19 combo. The et is definitely not plug and play but I like that about it. It is just mind blowing what you get for the dough which is a refreshing change in this hobby. Unless you are looking at buying the one on eprey from Greece for 2200.
When I hear people mentioning shortcomings I immediately think setup as it definitely takes some tinkering. If you are on the fence, try one, you won't regret it....