Dear Dover, You are probably correct, and the discrepancy is probably one of semantic nature. Maybe the Goldmund spec is "per minute", for example. That would make the GP Monaco much faster than the Goldmund, which we agree it should be. But I do take the point, which I myself realized after posting, that the term ultrasonic must mean that the correction rate exceeds the highest frequency of what we deem to be the audio spectrum, 20kHz. As to servo or no servo in the NVS, I went to their website, Dover, after you quoted from it. In fact, I do not see the word "servo" anywhere. Did I miss it? |
Have just pulled apart an old Goldmund motor I have lying around. I am impressed all over again with its speed sensing design. It has 164 slotts and 176 magnetic poles ( north plus south) in the speed sensor assembly, per revolution. This gives 14,432 counts if they only consider, say, north pluses and 28,864 if they use both north and south. My memory was a little out. Apologies |
So, Richard, are you inferring that the GP Monaco claims for the speed of their speed correction system are not so earth-shattering or envelope-pushing as one was led to believe, given what Goldmund did two decades earlier? The Reference was always an awesome device in my book, but the Studio, which I actually got to listen to, underwhelmed me. |
"So, Richard, are you inferring that the GP Monaco claims for the speed of their speed correction system are not so earth-shattering or envelope-pushing as one was led to believe, given what Goldmund did two decades earlier?" Goldmund didn't do it at all! They just sourced the motor and electronics....first from Papst then from JVC when the Papst motor was discontinued. Their claim to fame was the use of methacrylate and in the energy transfer path to drain away vibrations... I do the pink Triangle predated their use of acrylic (and maybe Merrill as well). IMHO neither Goldmund nor Monaco would have the resources to pull off a dd system in the way one of the Japanese giants would have back in vinyl's heyday. |
Lewm cc Richardkrebs I dont think the Goldmund numbers quoted are indicative of the sampling rate. I dont think you can count the number of wavy lines on a pcb and equate this to sampling rates. The Goldmund uses a coreless JVC motor. It uses a quartz lock servo. It is more likely that the wavy lines on the circuit board are used to generate a phase signal that is compared to a reference in a feedback circuit. The loop bandwidth of the feedback circuit determines the speed of the feedback loop. It would be more illuminating if Richardkrebs actually explained what type of motor the Goldmund uses, how its speed correction works and why he chose to abandon the TT self build project with this motor. |
Dover. Are we not getting off topic here? My reasons for dropping the Goldmund motor as a mule for my TT project will in no way advance this thread. It is an average motor with an above average speed measuring mechanism. Further you have described how it works. I only used it by way of example to back up my earlier assertion that high sample rates were used way back then. You are quite right, the sample rate and feedback loop bandwidth of two different things. It is probable that the samples are put thru several divider networks to bring the sample frequency down to a manageable level while simultaenously improving accuracy. (Other TT's of that era do this). I no longer have a circuit diagram so cannot confirm. And yes, wavy lines on a PCB under a multi pole rotating magnet are one way of measuring speed. Their output count is exactly as I described. Still used today in our industry for their robustness and long term reliability. |
Dear Lewm, yes, the 5 way horns changed a lot and improved the listening quality. In the last days I was frequently asked why I am offering my Micro SX 8000 II, my love baby - by which my real passion with analogue audio started. It is very simple: I am running out of space in "my small room". It is not a matter of drive technology at all. I have three big TTs left, two are belt driven ones, one is another SX 8000. When you are following the discussion about the TechDas, also a belt driven concept, one might get the impression that regarding the price there are three times more people getting a stake than it used to be some 25 years ago when the original design entered the audio world. |
Lespier/ Mosin Yes it must be very expensive to cover the R&D plus tooling for a complety new TT and motor. Mosin, perhaps you can give us some insight on this, from within the industry, when developing your spectacular TTs? Not DD I know but it would be informative to hear any comments you are prepared to share with us. Thanks |
Richard, Regarding R&D for my turntable, it is expensive. In fact, it is so expensive that I will probably never recover the costs. The time I tossed $1500 worth of spindles into a trash barrel comes to mind, as does the seemingly endless controller revisions. Don't expect me to forget the 79 NOS motors I bought, either! Was it worth it? Yep. I learned the hard way, but I suppose that's how it is with most small manufacturers. R&D isn't just about buying stuff and making parts, however. It really is about learning. You think you don't know anything, and then you realize that you have been eating and breathing it for a decade, so you must have picked up something along the way. That's how R&D works; it's incremental. Most small start-ups can't afford big time R&D, so their approach may be different from the Panasonics of this world. For me, it involved reading countless white papers that others had written. It involved making purchases of numerous vintage turntables just to see what makes them tick, and it included observations of other machines outside the audio realm. It goes on and on, and it is as much passion driven as anything else. When it is all said and done, I hope everyone who owns one of my turntables will enjoy it for a lifetime. My goal is to make a turntable for my personal use that I don't want to upgrade. Then, it's finished. Ketchup, I have a controller to run my turntable, too. Is it laboratory grade? I suppose so, but I never thought about it in that light before. I suppose calling it an audiophile grade controller would have been better, but nobody would be impressed in the least with a name like that. I honestly don't know what it should be named because it will have followers and detractors, no matter what. A story... My friend, Dave Slagle, has been working with strain gauge cartridges ever since I have known him. Not too long ago, he developed a new type drive for them, and he built one for me. He didn't provide a power supply for it, though. So, another friend gave me a laboratory grade power supply to run the thing. It says right on the panel "Lambda Regulated Power supply", and that's a known laboratory grade one. Does that make me happy? Well, I'm waiting for that genuine Dave Slagle audiophile grade one to appear at my house. It just goes to show, you can't please everybody no matter what you do. :) . |
Ketchup, In response to your question, which I think was aimed at Dover, I wrote after Dover's post that I visited the NVS website and did not find the word "servo" mentioned there, which still leaves open in my mind the possibility that they don't use a servo. They may have said they use a "laboratory grade" power supply, however. If I just missed seeing the mention of a servo on the NVS website, I do not mind being corrected. I have a laboratory here, albeit a biological one. In my lab we have many power supplies that are used primarily for electrophoresis. We don't generally use Lambda brand, but I have seen them in other labs. The voltage regulation required for a lab grade power supply used for electrophoresis is probably not as stringent as that needed in audio amplifiers and preamplifiers, or in the best AC motor controllers. I have always meant to bring in one of my meters and determine how much AC is present for a given set DC voltage put out by one of our lab units, but I have never done so. However, in other kinds of laboratories, especially where physics and chemistry are the subjects, I could imagine that voltage regulation is far more stringent. So, the term "laboratory grade", by itself, is fairly meaningless. |
Hi Richard, Albert Porter, Bill Thalmann I came across your new website today. As a hobbyist with no affiliation to any of you - congrats on the new site and good luck. Richard May I ask if this pic from the site is your personal TT / Tonearm setup or another customer's setup ? Cheers Chris |
Ct0517 Thank you for that. I gave up trying to build the website myself, so employed a professional. The triangular TT is my own design and build using a SP10 MK3 motor. New platter added 12 years ago. I have used this TT to develop my upgrade. Arm started life as an ET2. As you can see it has undergone a little surgery. |
Lewm - Re the NVS servo question : please read my posts more clearly. My post of 02-04-13 explains that the term "17 degrees of freedom" used on the NVS website under the title "Speed Control" indicates they use it. I included an explanation as to why. My post of 02-07-13 cites the Stereophile Review in vol 35 no 10. "servo controller with an active ultrasonic feedback loop" If you want to believe black is white, thats fine, but please dont misconstrue my posts. Thank you. |
Dover, Please lighten up. I am probably guilty of not studying your posts with the dedication that they deserve. Nor am I guilty of criticizing you if you might have been incorrect about whether or not NVS uses a traditional type of servo mechanism (meaning one where there is a device that directly monitors platter speed and feeds information back to a controller for compensation). You apparently inferred from the term "17 degrees of freedom" that they DO use such a servo. My error is apparently that I quoted you as having actually said that THEY say they use a servo, which perhaps is not the case(?) I am still not certain how the NVS works, but it is not a matter of great concern to me either way. As for "Stereophile Review", puh-leeze! I am sure you can find a better independent authority than that. As for believing "black is white", where did I do that? I am speculating, not believing. |
02-14-13: Ct0517 Thanks Ct0517, but I have nothing to do with the upgrades or the website but did lend my photos to Krebs since my table benefited greatly from the mods he licensed Bill Thalmann to do. I've known Bill for a good while and always tell people he is the guy that did my electrical and Krebs upgrade work. Even before this Technics stuff, Bill worked on my custom Dali (tube) crossover and greatly improved both the resolution and dynamics. I thought I had reached the limit since this was our third version of the crossover but Bill suggested a small design change that required few parts and it REALLY worked. I love recommending this kind of person to the community. |
I posted these same comments on Albert Porter's system thread. I also thought it might be useful on this thread, since I touch on all three drive systems that are the subject of this thread (Direct drive vs belt vs rim vs idler arm). My Technics SP10 MK2A has recently received the Krebs modifications and Bill Thalmann (Music Technology, Springfield, VA) overhaul of the electronics. I am using the MK2A in the stock Technics obsidian plinth, stock arm board, Graham Phantom Supreme 10” arm, Benz LPS cartridge, and Graham IC 70 phono cable connected to the Boulder 2008 phono stage. Please see my comments about the Technics SP10 MK3 posted earlier on Albert Porter’s system forum, the MK3 also having the Krebs modifications and Thalmann electronics overhaul. In short, this MK2A is an outstanding turntable. Speed stability is excellent, measuring on par with the MK3 using the Feickert iPhone application and the Analogue Productions test record, and passes the Sutherland Timeline test. Unlike the MK3, the MK2A doesn’t demand that you notice and praise its speed stability. Nonetheless, I never hear speed anomalies at all, and certainly not the “hunting” that direct drive critics levy against this breed. But let me be clear, in spite of the measured similarities between the MK2A and the MK3, subjectively the MK3 reigns supreme in speed stability over all other turntables I have used. One can hear this in extreme resolution, purity of musical lines, and low level detail. Visually, the Feickert iPhone application shows occasional periods of a straight horizontal line with a 1000HZ test tone with the MK3, but not with the MK2A. I suppose the summarized results in this application somehow average the results, because the single figures for both tables are very similar. In summary, speed stability on the MK2A is superb, but the MK3 is more superb. Sonically, the MK2A is excellent. As compared to the MK3, the MK2A presents musical images more forward in the soundstage with less defined outlines. Dynamics seem more spectacular than the MK3, although as noted in my comments on the Krebs modified MK3, dynamics with the MK3 are awesome and grow to staggering climaxes and subside with greater ease - more like the natural decay in live music. I have generally found these sonic attributes – forward soundstage and spectacular dynamics - fairly typical with turntables having all-aluminum platters like the MK2A. I hear these same differences with the Thorens TD 124 using its aluminum platter as compared to any of these alternatives – the Schopper platter (made with secret ingredients), the original cast iron platter, and the Mirko Djordjevic stainless steel platter. Otherwise, the MK2A is sonically opulent, rich and satisfying. Bass is powerful, mids are neutral and pellucid, and highs are excellent without sounding unnaturally extended. To my ears, the MK3 sounds more natural and true to the music in all of these areas, but this may be just a matter of taste. And could it be that the aftermarket copper, gunmetal mats and the like placed atop the MK2A platter diminish this difference? I don’t know, but some recordings sound more appealing on one table than the other. That’s why I love them both and won’t part with either one of them. My goal in experimenting with these vintage direct drives is to see just how good they can sound. Direct drive technology intrigues me for achieving extreme speed stability, a particular obsession of mine. My extremely expensive belt drive turntable is truly wonderful sonically in all areas except speed stability. I will continue to experiment with various aspects of these direct drives. As all analog aficionados know, *everything* in analog matters: platter/mat/plinth/ armboard materials, footers, arms, cartridges, loading, cables, what the cables touch, VTA, azimuth, overhang, absolutely level surfaces, static electricity, quality of electricity, platform isolation, RFI, ad infinitum and ad nauseum…and even looking at your turntable cross-eyed can make it sound bad on any given day. If analog didn’t sound so good, who would put up with it? Next steps are to improve upon the plinths, using Albert Porter’s superb design. I am also working with a Denon DP 80 (although the vintage Denon DP 100 should be a killer turntable, but it is alas unobtainable) and someday would like to play around with the reputably awesome Kenwood L07D. Here are some thoughts about value. The MK2A is by no means a shameful comparison to the MK3 – quite the contrary. The MK3 is so rare and expensive nowadays, why not try out the plentiful MK2 with the Krebs modifications and Thalmann restoration? The result is a superb value in high end audio, since new turntables achieving this level of sonic excellence are far, far more expensive. By way of disclaimer, I have no financial ties to Bill Thalmann, Richard Krebs and Albert Porter. I am really grateful to these gentlemen for enabling me to hear what these engineering marvels can do. |
For Richard (a Caravan tune from early days ;) ) "Ct0517 the TT under test was a Goldmund studio with a Syrinx PU3 arm and I think a Monster 2000 MC cartridge. I agree it was an astonishing finding which clearly demonstrated the effect of stylus drag. I hasten to add that I am in no way criticizing the Goldmund. It was simply correctly doing what it was designed to do. From memory it had a 2.5 kg platter with lead weights around its circumference. Thus for its weight, the platter had a relatively high moment of inertia." Way back in 1990/91 as a young man I owned a GOLDMUND STUDIO, would you believe ! But I didn´t have absolutely no idea of it´s speed stability as such, I hardly did know that such phenomenon as speed stability in record play existed, LOL. Young and foolish I was but eventually I had to get rid of the damn thing because I was so disappointed about it´s sound quality ! But I did realize one thing: Studio´s flimsy floating suspension is not a good idea at all. In fact it´s the biggest mistake GOLDMUND ever did. I changed it to ORACLE DELPHI MK.II.5. I lost a minor fortune but got much better TT instead. Oh, those were the days in the beginning of my hi-fi career... LOL. Of course, as we all know nowadays, ORACLE´s HANGING suspension is way better than Studio´s and probably all others´ implementations as well. I think ORACLE´s suspension is the very finest ever designed on the Planet, especially in the latest model the Mark VI with fluid damping. The belt driven ORACLE smoked the DD STUDIO in sound quality. With the SME III/SHURE ULTRA 500. Obviously the very compliant ULTRA didn´t like STUDIO´s flimsy suspension. Were a less compliant MC a better choice for STUDIO I would never know...:/ More that 20 years later I tried a direct rim drive with the DELHI platter... but that´s another story. Of course ;) |
Lewm Not directed to me, but the Basis Debut Gold is for sure hanging suspension. The four towers on each corner rotate to adjust hidden springs within enclosed silicone cylinders, allowing for both level and tweaking of the damping rate. Basis even offers different springs so you can adjust precisely for different tonearm mass. I owned two or three of these, the suspension system is well designed and very effective at isolating the table, arm and cartridge from floor borne input. |
Peter/Lewn My apologies totally forgetting BASIS turntables and their very sophisticated suspension system. I couldn´t find more info of its functional mode online but if it is tuneable/adjustable for different weighting TA´s everything´s OK. Well the BASIS flagship, The Work of Art must be something very special in suspended turntables, probably the very best designed so far. A stunning machine anyway. The SME seems also adjustable for certain TA´s so if it´s truly a balanced system it must sound good as well. A suspension hanging on rubber rings is an antithesis to metal springs. Likely both systems have a certain characteristic sound of their own, depending how effective the damping systems are. Albert, thanks for letting us know your BASIS experiences. To get the best out of a suspended deck its subchassis must be perfectly levelled, balanced & tuned for a certain arm/cart combination. When applied downward force on to spindle there should be only up and down movement of the subchassis, no wobbling sideways whatsoever. If not, the sound especially in lower frequencies is always smeared in some extend. A suspension must work mechanically perfect, this is the starting point. The ORACLE´s 3 spring suspension consists of 8 different parts in each spring ass´y. The latest model has also fluid damping added. It´s fully balanceable & tuneable for different TA´s. Yes, one can actually tune to a certain sound if necessary. To finetune an ORACLE is never easy but if one is married to one (for decades like me) it comes a second nature LOL. An ingenious system, but its manufacturing tolerances must be very low. In fact, I have owned 4 DELPHI´s, 2 MKII´s, MKIII and MKIV. The MK IV with hard mat was a mission impossible to finetune sonically, I didn´t like its stiffer spring ass´y at all. It sounded awful :/ And the MKIII was impossible to finetune mechanically due to a slightly wrong placing of the adjustment stems for the springs. But it didn´t sound so bad LOL. Let me take this opportunity to introduce you the ORACLE MKII.7 suspension in action (the video is very old, sorry for bad sound quality): http://www.youtube.com/watch?feature=player_detailpage&v=Ql9Gq6ir7hA |
"Other than that device the only serious attempt to elimate the off center LP problems was Nakamichi through its 1000 TT model and latter on with the Nakamichi TT Dragon. I don't know how easy or hard is to the LP manufacturers to have their LPs with a " perfect " hole centered. Today we pay a lot of money for new LPs/reissues and the like but the LP manufacturers never fixed that problem and IMHO no one of them take care about." Al the test records (vintage and new) I have tried have been also off-centered. One was 2 mm off-centered. I was forced to send it back to the seller because it was quite hard to test anything seriously LOL. |
I don't know how easy or hard is to the LP manufacturers to have their LPs with a " perfect " hole centered. Today we pay a lot of money for new LPs/reissues and the like but the LP manufacturers never fixed that problem and IMHO no one of them take care about." Here is a perfect opportunity for someone to create a press that punches out the center of an LP and provide an adjustable sleeve that allows for perfect centering of each LP. Of course you could not sell the LP once this was done, unless the next buyer was another fan of this product. Crazy idea? Hey, we had Audio Desk selling a rather expensive device to trip CD edge to make them perfect and by all accounts listeners got a nice upgrade after the tweak was applied. |
I am not sure if anyone has touched upon it, but in absolute terms, virtually every review I've read on Direct Drives say that stage width has a tendency to being narrower. Is this due to the fact that the motor is directly beneath the platter, and the magnetism has an effect on the upward downward portion of the record groove (the Stereo bit) Not only that but I am curious as to whether or not anyone has tried lifting and butchering a direct drive deck other than the Technics SL1200's - I say this because quite a few such as numark ttx's have really good specs |
Lohanimal, It is more a function of the error correction systems used in direct drive TT's. Like digital, they have inherent jitter that destroys the time and phase relationships of the music signal. This results in soundstage aberrations as well as a lack of resolution due to smearing. The designers of the SP10mk3 & Kenwood L07D tried to minimise this by running higher mass platters, but it is still there. |
Dover, While it's true that both the L07D and the Mk3 have heavy-ish platters compared to most DD turntables (the Mk3 having the heaviest platter I know of among all DDs), the two turntables are otherwise about as dissimilar in design philosophy as any two DDs can be. The Mk3 uses a mutipole cored motor and very tight servo control. The L07D uses a coreless motor and really very "loose" servo correction. The two turntables do sound different from one another. Can't speak to Syntax's dismissal of the SP10 Mk3 without knowing the condition of the unit that he auditioned and what else was in that system. What Syntax may not have liked about a stock Mk3, even assuming it was working up to spec, is addressed by the Krebs mods to the Mk3 (and to the Mk2). Anyway, if one does not like DD turntables, one may still be a good person. And vice-versa with respect to belt-drive. |
Syntax, had you heard depth and physical presence in that system before with a different turntable? I read that Artisan Fidelity does modify the power supply and electronics in the table and controller. Perhaps not the same mod level as the Krebs, but it is not stock from my understanding. Altering piano and trumpet tones sounds like speed deviation at a micro level, but isn't the Technics SP10 known for superior speed control, both accuracy and consistency? |
Lewm, Since this thread was started I have had further opportunity to listen to a Garrard 401/Raven/Zyx, Technics SP10mk2/Raven/Zyx ( both before and after full Krebs mod ) and Kenwood L07D all in the same system. The Garrard 401 presented a more musically coherent sound than either of the other combinations. Specifically the SP10mk2 sounded like it was slewing around, the Kenwood L07D had a bottom end/midrange/top end that was discontiguous. I have also had a listen to a Technics SP10mk3 with Ikeda arm/cartridge and SME V12/Air tight in the Porter plinth & Krebs mods and it sounded very good. So the only direct drive I have heard that is ok is the SP10mk3. There is a vast gap in performance between the Krebs SP10mk2 and the mk3. Having heard the SP10mk2 with and without the Krebs mods, my conclusion is that a Garrard 401 with decent plinth/arm/cartridge will outperform it. I'm sure there may be better DD's out there - the Koda Beat looks interesting. As far as I'm aware the Krebs mods are simple mechanical tweaks - there are no alterations to the error correction and servo system operating parameters which are limited by the 70's technology employed. As an aside the Technics based cutter lathe SP02 motor had significantly more torque than the SP10mk3 motor, and used a 60lb flywheel in conjunction with the higher torque to achieve stability. My Final Audio VTT1 with high mass platter/thread drive which came standard with a Sine/Cosine Wave generated power supply that requires a power amplifier to drive the motor, has far more solidity, explosiveness, micro dynamics and cohesiveness than any of the DD's I've heard. My second deck, the Platine Verdier, is unfortunately not in the league of the Final, but at least it has 78rpm and I use it as a test mule ( and it did outperform an SME 20/V in the same system ). |
Dear Dover, You wrote, "As an aside the Technics based cutter lathe SP02 motor had significantly more torque than the SP10mk3 motor, and used a 60lb flywheel in conjunction with the higher torque to achieve stability." Yes, the SP02 motor is even larger and has more torque than does the Mk3 motor, so what? The SP02 is designed with a different task in mind, that of driving the cutting of an LP. That said, the Mk3 motor is still the "torque-ist" motor among all the vintage Japanese DD turntables. I however would not use that fact to claim that the Mk3 must therefore be the best of the bunch; the Mk3 motor has to motivate a platter that is the heaviest of the bunch, and I would think that the high torque was deemed to be required to deal with controlling that excessive mass. Now, as regards your dismissal (or seeming dismissal) of the Krebs mods, it would seem you misunderstand the intent. The Krebs mods are designed in part to stabilize the relationship between the rotor and stator of the motor. When a servo correction occurs that invokes a speed correction, this applies a force that can momentarily disorient the relationship between the two components of the motor (Newton's Third Law of Motion, again). This phenomenon can then induce a "false" signal for servo correction, and so on and on. The net result is frequent servo corrections that emanate from the instability of the rotor/stator interface. Perhaps this is responsible for the coloration that some do hear with the Technics SP10 Mk2 and less so with the Mk3. (I certainly heard it with an unmodified Mk2, much less with an unmodified Mk3 in a 100-lb plinth.) Richard Krebs has devised some methods to stabilize the motor structurally that largely ameliorates the problem and thereby reduces or eliminates it, resulting in much less frequent servo activation. Also, you are not correct in saying that there are no changes made to the power supply/servo module. Bill Thalmann has devised several updates that are part and parcel of a "Krebs mod". And finally, we were not exactly living in caves back in the late 70s and early 80s when these products were devised and marketed. The major improvements in servo technology have more to do with miniaturization than anything else. Here I feel the need to repeat myself; none of the above is meant to imply that DD turntables, as a class are superior to BD turntables, as a class. I am sure your Final Solution TT is excellent. And I too love idler turntables; I would not ever give up my heavily tweaked Lenco. But I also adore my L07D, so I would like you to amplify on your critique: "Kenwood L07D had a bottom end/midrange/top end that was discontiguous". For example, did the unit you auditioned have a EMI shield between the motor and the underside of the platter? |
Lewm, To clarify a few points - My comment that the best DD I've heard thus far is the SP10mk3 is based on listening, not torque numbers. The Krebs modified SP10mk2 is in my view easily outperformed by a well set up Garrard 401. The L07D has always been one of my favourite DD's, but recent listening tests have led me to disappointment. The L07D was standard with the stainless mat which according to the literature is supposed to provide shielding. It is possible the L07D may not have been operating optimally. I say this because in my experience the power supplies in these vintage decks should be completely rebuilt and calibrated - not just the caps but all resistors should be replaced. For example in my outboard power supply built for my Marantz 7 tube amp, after 12 years I had it recalibrated by my tech. In that short time several mil spec resistors had drifted in value, despite being mil spec and overrated. The caps were ok but replaced with superior caps. With regards to servo technology, I think we are in agreement in recognising the issues around servos. Significant advances are available in speed response and accuracy, notwithstanding devices now switching at a trillionth of a second. The chips used in the 70's decks are obsolete, non programmable and slow. As an analogy, my Marantz 7 outboard supply, despite using regulation far more sophisticated that the ubiquitous LM317 and its like, would now be obsolete, the use of stacked op amps for regulation would be an example of using different new technology that can be utilised for providing better solutions to old problems. With regards to the Bill Thalmann/Krebs changes - my understanding is that Krebs has sent his own power supply to Thalmann because he couldn't get it to run, so I assume that he doesn't know how it works and any mods are more likely parts replacements or tweaks rather than a redesign. I'm also pretty sure in another thread Krebs has stated there are no changes to the servo operating parameters and design. |
I find that a fair point about the Sp10 mk3 having a torquier motor due to the heavy platter. It's engineered for purpose so to speak. the ratio of power to weight comes in mind and with it the EMT analogy that a needle/stylus is like driving a car up a hill - if it is small and powerful it can overcome obstacles and undulations quicker and better than say a truck. It is for this reason the EMT 950 platter weighs very little - so I guess it has a very high power to weight ratio. Simply put a single factor of itself needn't and often is not the only factor in an equation. |
To suggest the Technics Sp10Mk3, when properly conceived and implemented, cannot during playback recreate an accurate portrayal of an analog recording possessing the appropriate pitch, scale, speed consistency and balance is purely absurd. Numerous random variables come into play when evaluating such precision instruments, let alone vintage designs, especially when individuals are listening in foreign environments. In order to effectively and objectively evaluate two turntable platforms side by side, one must recreate the conditions present identically, period. Arm for arm, cartridge for cartridge and including associated equipment. Even then, doing so may prove less than absolutely precise. Frankly, based on what one individual described above "Tones are changing multiple times, depth and physical presence does not exist" this may indicate the logic / control / drive circuit requires a comprehensive scope bench test followed by servicing. Had these individuals bothered to examine the block diagram and troubleshooting guide printed in the service manual? Bear in mind, the Mk3's were intended to be used for extended periods of time while exhibiting utmost precision and stability during playback, namely in commercial environments, and thus were readily serviceable in the event of a malfunction. Over the years, in addition to the Technics Sp10Mk3, I've personally evaluated, studied and tested numerous other admired vintage designs at length, including the Micro Seiki RX5000 series and RX1500's with flywheel and many idler drive based ie. Lenco L75, Garrard 301/401 and various obscure direct drive based designs for that matter and in my experience none of these classics are entirely devoid of some type of inherent compromise. Fortunately, however, with today's technical resources and understanding of applied engineering principals, including material application, certain vintage based designs can still prove more than relevant and worthy of our praise. Peterayer, please PM me directly if you wish to know the extent of Artisan Fidelity's electronic service and mechanical upgrade services available for the Technics Sp10MK3 and how it differs from Bill Thalman's services and Krebs modifications. |
I asked my iPhone, "How many angels can dance on the head of a pin?" Siri then went into a lengthy dissertation on angels and arrived at the conclusion that angels are non corporeal and therefore have no dimensions in space; ergo an infinite number of angels can dance on the head of a pin. Dover, I am gratified that you've apologized to the L07D. Yes, the stainless steel "platter sheet" ought to go a long way to block EMI from the motor, but the addition of a second shield (ERS cloth, mu metal, TI Shield in my unit) under the platter sheet removed a kind of subtle glare that I did not know was present until it was eliminated by the added shield. The idea to try it came from the L07D Owners website; it turned out to be worthwhile. I don't know what was in the rest of the system that caused you to blame the L07D for a loss of "contiguity" among bass, midrange, and treble, but it would have to be a system (from cartridge to speakers) with which one was otherwise very familiar, in order to be able to blame the TT. Good point about the increased speed of modern day chips, but what is the evidence that these parts make a meaningful difference in design of a servo for a TT? The Grand Prix Monaco is state of the art in servo design, and no one is knocking down the doors to buy one (so far as I know). Bill Thalmann is much better equipped than I to discuss the servo mechanisms in these tt's, but I take his word that the circuitry is pretty sophisticated by modern standards, and in some cases he is able to upgrade discrete transistors to "modern" equivalents. Otherwise, I am on the side of both Chris and Richard, although they are professionally competitors with each other. Both are fighting the good fight, IMO. |
Lewm - There are no sides here. I am reminded of the old doctor who unfortunately misunderstood a lady who wandered into the clinic and complained of acute angina. I have been fortunate to acquire an exceptionable turntable that still outperforms anything I've heard, which includes the SP10's, L07D's and the big Micro Seikis. Ironically HP described the sound of the Final Audio VTT1 as "sounding like a direct drive TT" when he auditioned it in the 70's. Artisan Fidelity does a fantastic job restoring and improving turntables. In my view the old direct drives need to be blueprinted and recalibrated in every respect, both electrically and mechanically, due to age. The weak point of the SP10mk3 is a substandard plinth system that does not provide loop rigidity between platter/bearing/arm/cartridge. Artisan Fidelity build a new plinth with both far superior loop rigidity and and If you examine the Artisan Fidelity SP10mk3 upgrades - rigid plinth, energy drain to ground, copper record interface mat - the Final Audio had these attributes as standard back in 1971. In 1971 the Final Audio had a rigid skeletal plinth, the base of which is 40kg slab of Superplastic Zinc Alloy, at room temperature this material grain slides at a molecular level when excited between 10-100hz. The gunmetal arm pod is bolt to this energy sink as is the inverted bearing. A platform made by Otai composed of a constrain layered structure of hardwood plywood and crushed stone ( used as a base under the bullet trains ) was the recommended interface to sink any residual noise to ground (earth). The platter system uses 4.5kg copper mat and 18kg aluminium platter ( solid profile, not a ring bell shape ) and a gunmetal clamping system to drain unwanted energy from the stylus/record interface to ground. Final claimed at the time that even the shape of the underside of the platter had been designed to squeeze noise out. The Artisan Fidelity Statement 301 - has a 19lb platter composed of aluminium/copper with an inverted bearing - again the Final Audio had this back in 1971. As far as drive train goes - the Final implemented, back in 1971, a regenerated power supply that included sine and cosine wave generator, with infinite control of speed ( not stepped ) and control over the level of torque applied. The AC motor locks precisely, if an AC motor lags at all, it corrects sinusoidally, in a very benign manner. This drive train is more sophisticated than any of the big Micros and Melcos that came about in the late 80's, some years after the Final was built. The energy drain design of the Final again is far more sophisticated the the big Micros and Melcos as is the speed stability ( the Micros use DC motors ) So I am not anti drive of any kind - it is more about implementation. There are only a handful of exceptional turntables out there in my experience. |
Perhaps I missed it in the six previous pages of this thread, but there is an issue with belt drive suspended tables that is often overlooked. If the motor is mounted somewhere other than the subchassis along with the platter, then belt tension varies with suspension movements. There's no getting around this. Even if the belt has less stretch than rubber, the belt becomes part of the suspension. It's part of the suspension anyway in this case. Suspensions are designed to compensate for acoustic impact on the table and they're tuned to a low frequency. When one sets up a suspended table it's made to bounce straight up/down. This straight bounce only occurs if you push on the suspension precisely, and in the right place usually equidistant from the springs. Hit the suspension in the "wrong" place and the perfect bounce becomes imperfect. Sound waves don't obey the rules dictated by a suspension and will hit the table in unfortunate ways. I read a diatribe here about the Goldmund Studio and how the Delphi was so much better. It's true that the Goldmund DD's had an unfortunate suspension, but at least there was no belt involved. This was something that everyone came to realize and it became di rigueur to defeat the suspension. Okay, we're not talking about the stock table any longer, but a Goldmund thus modified was far superior to a forgiving Delphi with its mushy sticky mat and speed variations. Even without the suspension defeated it was a more precise deck capable of extracting more information. The methacrylate platter was a prototype for platters/mats that are designed for physical properties compatible with vinyl. It's no coincidence that Japanese statement decks of the late '70s early '80s were virtually all direct drive. When the CD was introduced in '80 they were phased out. The "superiority" of belt drive was sold to the public because that was the only option for a small manufacturer. They didn't have the technology or the motors to duplicate the Japanese decks, so they did what they could. Belt drive has come a long way and some are much better than those offered in the '80s. Now, well into the resurgence we come full circle. Before '90 VPI had the HW19 and the TNT was just introduced. Now their top deck is Classic Direct, go figure. |
Fleib, Your points are well taken; I am no fan of suspended tables, but suspension vs no suspension is yet another choice, in addition to, not instead of, belt-drive vs DD. As you note, a suspended DD turntable would not be subject to the belt stretch you mention. But in fairness to TT's of the suspended/belt-drive class, none of the current examples that I know of still mount the motor on the base, rather than on the suspended element. The old SOTA tables were guilty of that flaw; my Star Sapphire Series III was just awful on sustained piano notes, as a result. For years, I thought the muddy piano sound was part and parcel of vinyl reproduction. Modern SOTA tables are no longer built that way, and old ones can be modified, according to my reading. |
