The reproduction B60 has those flat faces on the huge nut that fastens from below, if that’s the part to which you refer. Yes, it’s very handy for tightening but wasn’t so handy for loosening, when recently I wanted to dismount the B60. I couldn’t get a wrench in there, and I was not able to turn it by hand. I therefore decided I could live without ever removing the B60. That’s what you call pragmatism.
Luis, True, the B60 is not required, but I think it does much more than add the convenience of VTA adjustment. Its mass (I think) per se acts as an energy sink for any vibrations that travel through the arm wand to the pivot, and it therefore adds a nice solidity to bass tones. I emphasize that this is an empiric reasoning on my part. I have not proven it. My FR64S is mounted in a B60 which sits in a custom made aluminum arm board on my QL10 (TT101) plinth. The arm board is further bulked up by a second heavy piece of aluminum that bolts up to the bottom of the board using a massive metric bolt. Thus the FR64S is very well anchored in a large mass of alu. (One reason I had difficulty removing the B60; it sits in a tight space.) I copied the concept from my Kenwood L07D.
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Found a photo of the Ikeda vt-vta-06. It LOOKS exactly like a B60. Whether it accommodates the same tonearms or only modern Ikeda equivalents, I do not know. Wow it’s expensive!
One consolation for the high price: Accessories like this one are highly desirable and will remain so over time, will never wear out or need rebuild unless you severely abuse it, so it's likely the resale value would remain high for many years or until vinyl dies again.
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N60 I think is different from B60, the one Nandric, Chak, and I have been discussing, which is dedicated for the FR64S and 66S. I think Chakster owns an N60 and a B60, both, so he is qualified to tell you the difference between them. As to the Ikeda vta-06, that's a new one on me.
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Dronepunk, be patient and persistent.
Chakster, I’ve seen videos from St. Petersburg. Enjoy it and the beautiful women while you may. Shutdown is likely to come, I think.
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dronepunk, Check eBay and the various sites where audiophile gear is for sale. Also check "Hi-Fi Shark". On that site, they collect "for sale" data from all other sites. I am confident you can eventually find what you are looking for.
Friends, we are all in the older age group, except Chakster. Please wear gloves and masks when you are in a public place, and wash hands, and stay well. Chakster, too. I am a physician and a virologist. This virus scares me.
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Nandric, One rule of thumb in laboratory science is never to let your results dissuade you from an otherwise attractive hypothesis. So, first of all, congratulations to you for having the patience to do the experiment. My first reaction would be that your experiment illustrates just how minute are the changes in VTF associated with changing arm height at the pivot by only 2-3mm; minute enough that your SFG doesn’t detect it. However, there is also the remote possibility that I was wrong; dynamic balance does eliminate or at least ameliorate the amount of change in VTF associated with small changes in VTA. I was wrong once before, in 1952, so I suppose it’s possible that I’m wrong again. Once every 66 years is still a good batting average.
But seriously, it depends upon how the dynamic balance apparatus works inside the FR64S. I’ve never seen a cut-away drawing. Nor have I taken one apart. You start by static balancing the tonearm and cartridge so the arm wand floats horizontally in air at the VTF setting = 0. Then you twist the knob to achieve the desired final VTF. In some way, the device creates a downforce equal in magnitude to the setting on the venier (or near equal). It would seem to me that the spring-loaded downforce would still be subject to changes in loading (meaning the shift in vector forces) at the business end of the tonearm (the stylus), when the vertical position of the pivot point goes up or down in relation to the stylus tip. But I am willing to admit, maybe not. If not, I’d like to understand why not. I’ve read all the propaganda about dynamic balance preserving VTF over warps, etc, and I’ve swallowed it whole, until now.
Aha! I see how you guys might be correct. The downforce is entirely supplied by the built-in mechanism. Therefore, it is, over a certain part of the arc of the pivot point, independent of gravity (because the arm "thinks" it's balanced, end to end, like a seesaw). It would be, so long as the artificial downforce, supplied presumably by springs, remains linear as the arm moves up and down due to LP warps and whatever else would perturb the tonearm. At some point, as the arm wand moves down or up with respect to the pivot, I would not expect the force to remain constant, because the force of a spring is directly proportional to its compression or extension. But for all practical purposes, I concede. |
N Andric, I think you are saying that the VTF in the FR 64S is largely governed by the spring that applies the VTF Which is controlled by a rotary knob on the side of the tonearm. I don’t think that makes any difference. If you have adjusted VTF with the arm wand level to the LP surface, and then you crank the B60 downward , there would be additional force over and above the adjusted VTF, distributed according to the new angle of the arm with respect to the surface of the LP. In words, there is always some additional gravitational force on the tonearm in addition to whatever you have cranked in using the spring. The spring doesn’t cancel gravity. Try it and see. |
ct0517, The change in VTF associated with the typical minute adjustments to VTA/SRA is not worth worrying about. You can calculate it as a percentage change, if you know your geometry and vector algebra, but it will be tiny and not worth your concern, at least not to the degree that you appear to be concerned. Do you change VTA (or SRA) with every LP? I cannot be bothered.
Anyway, changing VTA by using the B60 is no different, in terms of its affect on VTF, from changing VTA by any other method. So, if you are one who changes VTA frequently, and if you perceive this to be a problem with respect to VTF, the B60 is neither here nor there, except that it is a very convenient way to change VTA, if you own an FR64 or 66 tonearm. I happen to think there is a secondary benefit to the B60; it adds considerable mass to the base of the tonearm, which (I think) helps to soak up resonant energy and improves coupling to the turntable and bearing. |
ct0517, The answer to your question will vary according to how the tonearm is installed into the B60. If, for example, the lowest adjust point on the B60 places the tonearm parallel to the LP surface, then the highest adjust will raise the rear end of the tonearm with respect to the LP surface and will therefore slightly increase VTF. And you can see how the result will change, for example, if the lowest adjust point on the B60 places the tonearm either raised or lowered, at its pivot point. So, yes, there will always be a change in VTF associated with changing VTA, but there is no rule you can derive from the experiment you asked us to do, unless you know how each responder positioned the tonearm to begin with. |
Hi Nicola, I don't seem to have that problem with mine. But I would be interested to learn whether others have a had an experience similar to yours. Is there only one source, or are these replica B60s coming from more than one fabricator? I bought mine about 2 years ago from an eBay vendor who was either in Hong Kong or somewhere close by. |
By the way, apart from the esthetics, do you have any problem using your sample of the B60? From your verbal description, it sounds as if the glitch would be an annoyance but not a real malfunction. But perhaps I misunderstand exactly what is going wrong. |
Dear Nandric, You have my email address. Would you be kind enough to send your photos to me? Then we can "know" whether you and I, at least, are talking about the same item. I put the word "know" in quotations so as not to provoke a philosophical dilemma for you. I think you are probably correct; there is probably only one replica, sold from several different sources depending upon the whim of its maker.
Dear Dover, Obviously, if the mount allows the tonearm to wiggle side to side or especially up and down during actual use, that is totally unacceptable. Obviously. However, I understood Nandric to be saying that his "B60" was not malfunctioning to that degree, but that's why I asked my follow-up question to his original post. I won't make a categorical statement comparing the DV505 to the DV501 (which I also own), or the DV505 to the FR64S cum B60 replica, because I think such comparisons are highly dependent upon the cartridge being used. The FR64S affords a much higher effective mass than does the DV501 or 505. What cartridge(s) did you use when comparing them? |
Dear Syntax, It was the very rarity and cost of an original B60 that prompted me to "take a flyer" (as we say in the US) on the reproduction B60. In quality of construction and materials, I am not disappointed; it's beautifully made. So far, mine does not do the bad things that Nandric reports. He sent me a photo of the damnable screw; I am going to find out whether mine is the same, or not.
I would never use an FR tonearm without the B60. It should have been standard equipment. |
Dover,
That's a very interesting summary, and you certainly do have a lot of listening experience that enables you to speak with authority on the products you've listed, or at least it qualifies you to have an opinion. Did you sell the Klyne 7 phono? (I'd be interested, maybe.)
Your choice of the Marantz 7C "uber alles" is a big surprise to me. Has yours been modified/upgraded/etc? It almost certainly cannot be all original, since any electrolytic capacitor made in the 1950s or 1960s is dead by now. Also, the germanium diodes used at that time are probably kaput. It's been decades since I owned a 7C, probably pre-dating the hegemony of MC cartridges, so I cannot recall whether it would have had sufficient gain for a true LOMC, but has yours been modified for more gain than original? The 7C was a wonderful piece of gear that I often regret selling, not because its sound quality was transcendent but because of its historical significance and the perfection of its design, the same reason I have kept my Leica M3 and its lenses. (Same reason I should never have sold my Porsche 550RS Spyder.)
Nikola, As I think I said by private email, I don't have issues with my faux B60, yet. There is no horizontal "play" in the mechanism. I agree the lubricant used is annoyingly "sticky", but I will leave it alone. It's really a simple device, and even the reproduction is overbuilt compared to some other devices that accomplish the same end for other tonearms. |
The load resistor might affect frequency response but not gain. However, I too am wondering about Dover's claim that his 7C has adequate gain for "any" LOMC cartridge. I tend to think his unit must be modified, but he will tell us. |
Dear Dover,
"As is always with audio it is a sum of the parts." Set that in stone. I totally agree and have operated on that principle for the last 10-15 years. A knowledgeable DIYer can dramatically improve upon almost anything commercially available. I am also not surprised that your modified Marantz blew away the Jadis.
I also agree that securing the vertical shaft of the typical VTA-adjustable tonearm with one or at best two grub screws does not make me feel good, yet its most commonly done. Even the B60 only really uses two set screws. One of the brilliant aspects of the Kenwood L07D integrated turntable/tonearm is the massive and very mass-y clamp that secures the tonearm once one has set the VTA. As regards your friend's consternation that "old stuff" sounds good, I also intentionally out-fitted my Beveridge 2SW system such that nothing upstream is less than about 30 years old, just for the fun of it. But of course I modified and upgraded almost all of the components I chose. The wheel was invented a long time ago. At first I used a Quicksilver preamp vintage about 1980-85. The circuit has many odd features, by present day beliefs, but on the other hand, the power supply is well done. One big improvement was to sub all the caps in the RIAA network with Russian silver mica caps available on eBay. And to replace the 12AU7 cathode-follower with a 12FQ7. Etc. After the Quicksilver, I moved on to a hot-rodded Klyne and a very hot-rodded Silvaweld phono stage. But this is hijacking Nikola's thread, except for the bit about set screws. Sorry, Nikola. |
Duelands won't fit into my budget, let alone into my chassis'. Although I am a stickler for parts quality myself, where "affordable" (everyone has a different definition), my experience tells me that tweaks to the circuit itself (such as what you did to your 7C) are far more efficacious than parts swapping. |
Dear JCarr, Touche'. The problem with my statement is that it was general and followed Audpulse's specific comment about a 47K load on an MC. Are you suggesting that the load resistor never has any impact on frequency response of an MC? If so, teach me. I thought that very low values of load resistor (i.e., high loads) can dampen the HF response, of some MCs in some cases with some loads. So if I am correct, then perhaps there should be an industry-standard ratio of load resistance to cartridge internal resistance, for published tests. Anyway, who ever publishes curves these days, for cartridges? Even S'phile takes the subjective judgment of its reviewers as gospel.
My main point was that unless the load resistor is much closer in value to the internal resistance of the MC cartridge (where 47K would of course be maybe more than 1000X the internal resistance and could have no effect at all on gain), or certainly if it's less than the internal resistance, it will not have an appreciable effect on gain. |
Ugghh! Syntax (the linguistic, not the person) is my bete noir today. In my second paragraph above, I mean to say that the load resistor can affect gain if it's value approaches, equals, or is less than that of the cartridge. |
Dear JCarr,
This is what I found, quoting your quoter:
"Regarding loading of low-impedance MC cartridges, in general I recommend trying to reduce any capacitances present between cartridge and phono stage input to as little as possible. Use the lowest-capacitance phono cable that seems decent, turn off any additional capacitance in the input stage of the phono amplifier etc.
The reduced capacitance should make it possible for you use a wider range of loading impedances without having the sound go bright, peaky or thin-bodied. Conversely, any excess capacitance between cartridge and phono stage input will almost certainly force you into choosing lower loading impedances to save your ears.
Being able to use higher-value loading impedances should allow you to hear more of the dynamics and resolution that the cartridge is capable of, while using lower-value loading impedances will limit how much of the cartridge's dynamics and resolution that you can usefully extract."
So now I am puzzled; were you inferring that my statement (essentially, low load resistances that get into the range of less than a multiple of the internal resistance can affect FR of some cartridges) was correct or incorrect? I said nothing about capacitance. You seem to be saying here that if the capacitance is minimized, then one's choice of load resistance is widened. I don't see a conflict. |
Dear Jonathan,
I take your point on frequency response, and I am sorry I ever wrote it; it was really beside the point of my post.
On the matter of load resistance, I SAID at least twice, albeit perhaps badly, that load resistance CAN affect gain, but not perceptibly unless the load resistance gets down low enough in ohmic value such that it is less than a multiple of the cartridge's internal resistance. The case in point was 47K. Surely a 47K load is not going to have a perceptible effect on reducing the gain of any MC cartridge. The reason I left it vague as regards the critical minimal relationship between phono input resistance and cartridge internal resistance that seems to preserve gain, is because there does not seem to be much agreement among those "in the know" as to what relationship is acceptable vs what relationship WILL result in a perceptible loss of gain. Classically, if you read elementary texts aimed at audiophiles, the relationship between output and input resistance is often said to be at least 1:10, in order to avoid perceptible loss of gain. But with MC cartridges, I have read all sorts of claims; it seems to be a "muddy" area. Many claim to be able to go below a 1:10 ratio with no perceptible loss of gain. (For example, the legions of Denon DL103 users who select 100R and less to load that cartridge.) I personally have never tried going below 1:10, so I cannot comment up or down, let alone have I taken measurements. One manufacturer who is also a friend of mine suggests that one might progressively reduce load R until one does perceive loss of gain, then go back up to the next lowest value of load R as the optimal choice for that particular cartridge. I've never tried that either. I am guessing you would not approve.
So, back to the original bone of contention, all I meant to claim was that 47K ohms is not going to perceptibly reduce the gain of any MC cartridge. Thank you for correcting the part of my statement that was apparently erroneous, with regard to the effect of load on frequency response. If you say so, I accept that I was wrong. You certainly know more about this subject than I will ever know or need to know. |
2 meters + ~ 6 feet, 6 inches. Now I translated it to the British/American language, I am impressed too, if this is Syntax's actual height. Let's see: the only major areas of disagreement between me and Syntax is he dislikes Koetsu and all MM cartridges, and I like my Koetsu Urushi (no opinion on stone-bodied, Rosewood, etc) and several MM cartridges. BUT we both like ZYX and FR tonearms. I will have to post more about the latter products, I guess. On the other hand, Syntax is not going to knock on my door without first expending a great deal of travel time.
As Thuchan likes to say, "all in fun". (However, it seems Thuchan was offended last time I questioned something he wrote, even though it was all in fun.) |
JCarr,
Not to worry. When I am corrected or my views are "modified" by an unimpeachable source, such as yourself, I take it as a learning experience. Furthermore, I am all for dispelling BS that prevails in this hobby. |
