I want to retract my criticism of Dover for his dumping on vintage direct drives. He has a perfect right to say what he wants, and thanks to JP Jones for his informative responses to Dover's points. On the question of the L07D servo, I think it does say in some vintage factory literature that the servo is only activated when there is a fairly significant deviation from correct speed. Having read that, I came to think of the L07D as an attempt to achieve constant speed partly through the use of a heavy platter, a la many belt drive turntables. While the platter is not very heavy, as compared to some behemoths found on belt-drive turntables, it does have its weight concentrated at the periphery, so as to maximize any flywheel effect, and Kenwood did also supply an optional fairly heavy peripheral ring to add to platter mass where it does the most good. When you use that ring, you also engage a switch on the power supply that changes the operation of the servo circuit.
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I own a Mk3, an L07D, and a TT101. I listen to each of these regularly. They do have a very subtle sonic signature I think, but the last thing I would do would be to try to describe it in words, for one thing because of the factors that JP mentions. Moreover, the differences that may apply are very subtle and certainly would not include a perceptible issue with speed stability. What I wonder, however, is why Dover is so intent upon discrediting these vintage turntables. It’s all very well to love and prefer whatever it is that you own over all other TTs, but why does that require that all other solutions to the problem of playing a record are wrong or sub par? If you want to say that direct drive turntable X is superior in speed stability to these vintage direct drive turntables and in the same price range, that would be very interesting, and I would like to hear about it. |
In Miami, you can get the best rum from Cuba, easily.
I view JP as something of a genius with direct drive. He fixed my TT101 after several very smart and competent persons had tried and failed over a period of 2 years. And I am pretty sure that mine was the first Victor TT he ever worked on. He found a crack that ran across a tracing on one of the PCBs, causing an intermittent problem. The defect had eluded detection because it ran underneath a glob of solder, rendering it invisible unless one knew exactly where to look. I don’t think he had to replace any parts at all. I’ve also got his chip in my SP10 Mk3. |
What are the character flaws in your TT101? Does it sing the song of the Volga Boatmen? Does it run on Vodka?
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I paid $700 for my custom pure copper L07D mat. The L07D comes with a stainless steel mat. My copper mat is an exact replica, weighing only a few ounces more, and includes the threaded holes provided in the original for lifting it off the platter. Why did I do this, you might well ask? Because I had convinced myself that copper would be a better shield from any EMI coming from the motor. I have to say the copper mat sounds better, but why it sounds better I cannot say.
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While I am sure that the M-S metal mats are very good, based on the accolades, the cost is more based on the mystique that now surrounds anything made by M-S in its heyday. That was my point. I had a new pure copper mat custom-machined for my Kenwood L07D. (It looks a lot like the one that someone else posted in a photo up the thread.) It was not cheap, but it did not cost nearly as much as an original M-S mat.
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"and expensive", not "and the expensive". Autocorrect on my iPhone.
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Mats come and go, and it’s common for the best of them not to be recognized as such until they are no longer being produced, whereupon they become”rare” and the expensive. We audiophiles are a crazy bunch. |
Never heard of the TTM mat. Is it still in production?
Also, Hi Albert! |
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tzh, way above the cost of a fully refurbished Mk3, there is a small universe of megabuck direct drive turntables, let’s say at prices of $30K and way up from there. Although I like my Mk3, I don’t assume that one or more of those turntables might not be even better. Surely, based on JP Jones data, the SP10R at a more pedestrian price point is as speed stable. |
As I mentioned somewhere above, JP Jones did a head to head comparison of the speed stability of his newly acquired SP10R compared to his own SP10 Mk3, no doubt being run by his module that replaces the MN6042 chip. The curves were virtually super-imposeable. Those data were published either here or on Vinyl Asylum, I think.
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Dover, Good to know you have actually had hands on experience with an SP10 Mk3. And yes, of course I realize that computer technology is now way ahead of anything available in 1980-ish. You guessed correctly; I probably didn't even own a computer back then. But I also don't think that running a motor at 33.33 rpm is in any way comparable to the complexity with which a modern home computer has to operate. The SP10 Mk3 using the JP Jones module in lieu of the original MN6042 and with the Krebs mod is a superb turntable to my ears. I was hoping that JP Jones would get in on this conversation, because he speaks with an authority I cannot muster when it comes to the electronics. I've often read about the Grand Prix Monaco and the precision of its speed controller out to at least six digits after the decimal point. Yet the thing was never a big hit with the public. That could be due to elements of its construction such as platter composition and mass and other factors having nothing to do with its apparently stringent speed control. Could it be that their latest "upgrade" besides being accurately reported (I am not implying fraud), is also a marketing tool meant to revive interest in the product? Like the old days when one solid state amplifier would tout .01% HD until another would tout .001% HD and so on. We ended up with the Phase Linear 700W amplifier with .0001% HD and an awful sound. (A red herring, I know.) Seems to me in the world of servo design for turntables, different engineering groups have espoused different approaches. Some have favored a "loose" control over a tight one. I believe NVS is one of those that minimize the frequency of corrections. Among vintage turntables, the Kenwood L07D is in that latter camp. The art of DD turntable design is as much one of taste and personal listening preferences as it is an absolute science; I think that is another way in which the analogy between modern computer design and operation, where speed and capacity are undeniable measures of performance, and DD turntable control breaks down.
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Dover, Stop. Why don't you and Richard just have a duel at sunrise. Water pistols to be the preferred weapon of choice. As soon as his name is mentioned, out come your familiar attacks. New Zealand is a beautiful and wide open country, and I am sure there is room for you both.
JP Jones at Fidelis is very familiar with all the various servo systems used by the various modern and vintage DD turntables, and I am sure he would have a lot to say in rebuttal of your issues with the Mk3. The MN6042 is the primary controller for the motor (not just one of several such parts), and JP's replacement module made from modern SMD parts is a bit superior to the MN6042 in doing that job, but not all that much. In my opinion, what you are hearing from the Mk3 that you find objectionable has nothing to do with the servo, unless you have been listening to a subpar unit and assuming in fact that you have ever had an extensive listening experience with a Mk3 in your own system. Do not assume that the Mk3 is just a bigger stronger Mk2. It's a whole different and more colorless world. I can say that having owned both and having had them side by side in the same system.
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best-groove, "Frusciant"? I gotta look that up. Actually, I did look it up, and I didn't find it in any on-line dictionary.
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Ditto to what Atma-sphere wrote. Chakster, the Krebs mod is to stabilize the stators. As you know, in a DD, the platter is generally the rotor of the motor or is affixed firmly to the rotor assembly. In the case of the Mk3, a gigantic ring-shaped magnet is fixed to the underside of the platter, so the platter IS the rotor. When the motor spins the platter, there is an equal and opposite (in direction) force applied to the stators. Any movement of the stator assembly in the direction opposite to that of the platter can at least hypothetically cause the servo system to "think" there is a speed anomaly that it needs to correct. This can result, at a micro-level of course, in the servo hunting for correct speed. Since the Mk3 has the highest torque motor ever used in a DD, to the best of my knowledge, this is a potential issue especially for the Mk3. What Richard Krebs devised is a method to further stabilize the stators so as to eliminate that phenomenon so much as is possible. My Mk3 was purchased NOS, and I listened to it for about a year prior to having it Krebs-ed by Bill Thalmann, his agent in the US. I hear a subtle improvement in terms of "smoothness" and therefore "musicality". (You can jump on me for using those vague descriptors, but they fit what I hear.) Before the mod, the Mk3 was already the most accurate TT that I own, but in some ways it was a bit clinical sounding compared to the Kenwood L07D which sits right next to it and feeds the same system. Now I can hardly tell the difference between them except for the fact that the Mk3 is still bang on accurate. I hope I am not putting words into JP Jones' mouth, but he compared speed accuracy between his tweaked Mk3 and his own new SP10R and found in terms of that parameter virtually no difference. Which is why I was able to resist buying a 10R in Tokyo, where you can buy one for under $7K.
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When you say hard to beat at the $7500 price point, do you refer to your idea of its value AFTER you do the upgrades, or what? Because first of all, it's probably worth more than that just as is, in terms of market value.
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