Vintage DD turntables. Are we living dangerously?

Thanks, Halcro and Banquo. To answer Halcro, the symptom is as follows and as I described it before, except now that it is constant, I can make more complete observations: The tt starts up fine. The tach will show it ramp up to the 33.33 display, but within usually less than a minute at speed, the tach will start to display errors, e.g., 33.34, 33.32. Very shortly thereafter (within several seconds), the power goes away and at the same time I now see that the motor assembly "shudders", vibrates enough to shake the chassis, just before power goes away and tach display will go blank, except for the decimal point. The brake does not activate; the platter coasts to a stop, as if one pulled the plug, but the Power light is on and the decimal point remains lit. I suspect that the shutdown is a safety mechanism that saves the motor from damage.

Banquo, Between me and Bill Thalmann, I daresay about 70% of the solder joints on my TT101 have been re-done. And the ones that have not been re-done are OK by inspection, not that that means they actually are OK. Every time I fiddle with the TT101 I re-do a few perfectly good looking solder points. Eventually they all will have been re-done. Will the damned thing work then? I doubt it.

Halcro, You wrote, "The ICs were more difficult as many of the test figures in the Victor Service Manual didn't make sense or were simply wrong." Are you referring to the DC voltages on the pins of the ICs? I ask, because I measured some of the voltages at the pins of one IC that is suspect, and they do not at all match the predicted readings posted in the Service Manual for that IC. This led me/leads me to believe the IC may be faulty. But if my interpretation of what you wrote is correct, maybe I need not worry about it, unless or until I have further evidence of its malfunction.
Please confirm.

Banquo, where do you live, and who is your tech? Is it Bill Thalmann? Thanks.

Halcro, Continuum is dead. Long live Dohmann. Apparently, Mark Dohmann, one of the principles of Continuum, is now producing a tt on his own, for about $36,000 with a Schroeder LT tonearm, a relative bargain compared to the Caliburn. He is said to have developed the new tt in collaboration with several others with various types of expertise relevant to the project. But this is not a DD, nor is it vintage.

Yes, definitely provide some ventilation for a TT101.

Hiho, You may be correct. I found two sources of info that conflicted with respect to the nature of the Schroeder tonearm optionally supplied with the Dohmann tt. One claimed it was the LT; the other did not.

I don't have a Minus K or its equivalent, but one of my two systems is located in my basement on concrete flooring poured over solid earth. My subjective impression is that this has amazing benefits, compared to upstairs in my living room, where I would probably notice a Minus K.

If Dover and Richard (and Fleib) were to refrain from commenting, we would all be the poorer for it, and this fun thread might be dead. Carry on, gentlemen.

Just a note from the peanut gallery:
Halcro, you and Richard are actually in agreement. The statement from Feickert (or whatever was the outside source) was that record eccentricity will produce a regular irregularity in the frequency, forming a sine wave around the center frequency. Since one is interested in wow and flutter due only to tt platter speed variations, that sine wave must be filtered out or subtracted from whatever is the actual wave form. The remainder would constitute w and f due to the tt only. Ideally, that would leave a straight line, if wow and flutter due to the tt were zero. I think we can all agree on that, including you and Richard.

Dover, No one can be absolutely correct, except you. I should have remembered that from past experience. Not that I would argue with your obvious point here, your condescending attitude notwithstanding. Instead of "due to the tt only", I obviously should have written "due to factors other than LP eccentricity" or words to that effect. The point was subtracting out the sinusiodal noise due to LP eccentricity. Serenity now!

"Small ones" does not tell me much. Some electrolytic caps in solid state devices can have values as low as one microfarad and below. Such caps are tiny, but they are nevertheless electrolytic. If they are electrolytic it would seem to me they are subject to aging, leakage, etc. I would change them all, and I did so in my own SP10 MK2. If the term "small ones" refers to film and foil or metallized film capacitors, that is a different story. Film caps are also "small", but they have a very long life and don't really need to be changed unless grossly bad. That's what I think.

Dear �Nandric, Go ahead and buy that TT101, if you want it. Here is a URL for the owners manual AND the service manual, which can be downloaded from Vinyl Engine:

http://www.vinylengine.com/library/jvc/tt-101.shtml

Armed with the service manual, any really good technician worthy of the name can repair the TT101, save for the "unobtainium" chips, that might not be so unobtainable. To add to Ralph's cautionary comments, I would say that the first thing to do after acquiring a vintage dd with unknown service history is to have all the electrolytic capacitors replaced. After 20-30 years, it is quite likely that at least some of the caps are leaky or otherwise defective. Leaky caps can lead to destruction of one of those precious ICs. Also note (Mgreene) that no vendor asked me to purchase the Denon chip in bulk. I had the choice to buy only one or as many as I wanted.

In the US, Bill Thalmann of Music Technologies in Springfield, VA, can repair any of these tables, is extremely smart and honest, and is an audio hobbyist as much as we all are. Music Technologies has a website.

I wouldn't "dabble" in vintage dd turntables if I did not sincerely believe based on listening in my own home on my system that they offer superior value for money, based on performance alone. The fact that they will not depreciate if properly maintained is only an added bonus. Of course, some are better than others.

It does seem odd that the owner of a business that thrives on selling used gear would make the statements about dd attributed to him by Henry or Henry's source. Based on the results of my Google search, those Denon chips seem to be available all over Hong Kong, if he would stick his head out of his door. C'est la vie.

Dear Henry,
The question you raise has also interested me from time to time. The internet is full of information on motors. However, much of it is written using jargon that is unfamiliar to me and therefore quite dense. But here goes my current understanding: (1) Not all cored motors have 24 poles. A cored motor can have as few as 2 poles, but such a motor would exhibit a pronounced cogging effect. Cogging is the tendency of a motor to want to stop when the magnets are aligned such that the distance to the attractive element is minimal. Obviously, in turntable motors, we do not want cogging. In general for cored motors, the more poles, the less cogging effect. A 24-pole motor is likely to exhibit markedly reduced cogging compared to a 12-pole motor. The SP10 Mk3 has a 24 pole motor. If the Victor TT81 does, that's good. (2) Coreless motors either have zero cogging, because there is no iron in the windings, or they have very little cogging. (I have trouble with this issue, since I see contradictory statements on the internet, but it seems to make sense that coreless motors would not "cog"..) As far as I can tell, coreless motors do not have "poles" per se, so the question is irrelevant. I have also seen the statement that "slotless" motors have zero cogging. Whether coreless and slotless are synonyms in motor jargon world I have not yet figured out. In any case, the L07D and TT101 motors would have zero cogging, most likely. I think this gives rise to the "fluidity" that Hiho and I hear. Did you notice such a thing as regards the difference between TT81 and TT101? If anyone has a clearer understanding of the consequences of coreless motor design, please jump in here.

Aigenga, I think what you wrote could also be termed an increase in "fluidity". In any case, what you wrote would be another fair description of what I hear with the L07D as compared to other DD turntables I have owned which use motors with iron or steel cores. (Jury is still out on a comparison of L07D to Technics SP10 Mk3, however. Mk3 has fantastic "liveliness", for sure.) However, let me caution that this is the type of deductive reasoning one should really avoid (relating the L07D's fluid sound to the lack of cogging of its coreless motor), even though I am guilty of it here. The one observation is not necessarily related to the other factoid.

Hiho, The information I have been able to gather suggests that it is simply more difficult to get torque out of a coreless motor than out of a similarly sized cored motor because the coreless motors tend to trap heat and thus overheat, and overheating is lethal to them. (The iron or steel core in a cored motor also makes a good heat sink, so motors intended for heavy duty and continuous operation tend not to be coreless.) However, the Pioneer Exclusive P3 (coreless) motor is second only to the Technics SP10 Mk3 motor in terms of torque among the TOTL Japanese DD's, as far as I can find out. (Perhaps the Denon DP100 motor develops more torque than that of the P3; don't know. It's as big as a coffee can, so I would not be surprised.) If you read about Kenwood's thinking in the design of the L07D, they actually did not favor high torque in principle. So they were not concerned with competing in that "horsepower" race. Also, the drive system (the implementation of the servo mechanism, use of a quartz reference, handling of the AC and/or DC, speed of the sensor mechanisms, etc) are also determinants of the success of a DD design; cored motors can be made to work just fine, IMO. The fact that Denon and Technics stuck with cored motors does not necessarily mean they were "stubborn". However, like you, I am not a motor engineer. Motors and how they work, what makes one better than another for this or that application, are fascinating and complex subjects.

Apropos of that, you cite the Brinkmann Bardo for using a coreless motor, and I did too in one of my earlier posts, but does anyone know about the Grand Prix Monaco, the NVS, or the Teres Certus? For that matter, what about the Brinnkmann Oasis?

You have to ask yourself what is the cost of "tech time" as compared to the value and rarity of a TT101 and the pleasure you derive from it. But meantime, you can order the capacitors from Mouser or Digikey on-line (assuming you live in the USA). I recommend Panasonic or Nichicon brand. Dirt cheap compared to the consequences of not doing it. Once you have the parts, you might take it to a technician and get an estimate of labor cost. I would be surprised if it would take much more than 2 hours to do them all. I would offer to do the work myself, except..... I won't. The other side of this coin is that you may not be getting the best out of your unit at present, even if it "works", due to a few bad capacitors. (Last time I looked, DD turntables were not generally designed to require a push-start in counter-clockwise or clockwise direction.)

Thanks, Downunder. I hardly think that the speed and precision of the P3 is due to its fast start. One is not listening at the start. Yet there does seem to be a consensus that a sense of "speed" or pace or whatever like that is superior for most direct drives vs most belt drives. For one thing, this may have to do with belt creep or belt stretch; no matter how sophisticated is the motor drive, it's work is applied to the platter via that belt.

Hiho, Great photos of the LO7D motor coils but the photos at the website only get one to an index page and for me the URL goes dead at that point. Not to worry. I am wondering whether the guy you referenced is correct when he implied that the assymetric placement of the coils on the original LO7D motor and on the Bardo motor would result in aberrant drive from the motor. I think the field created by the coils would average itself out. (I also think there would be a limit to the odd spacing where once reached the field would no longer be able to average itself out and would result in a dead spot on each rotation.) But this is just idle speculation and curiosity.

He said or inferred that the Dual CS5000 would have an EDS coreless motor. But based on what I read at the Dual history website, that may not be the case. Just what models of Dual DO in fact have the EDS motor. I think their idler drive tts, like the 1019, have induction motors (a la my Lenco).

Based on your last post, I would not worry one bit about that hum. (Obviously your TT101 was built for 120V.) But if you like to worry, I still would not go to a lot of trouble and expense to move all the electronics out of the tt chassis, if indeed it could be done with the TT101, which as H pointed out is quite complex, and quite a bit more complex than an SL1200.

Do you like the EPA100 significantly more than the UA7045? I always thought those Victor tonearms might be sleepers and have been tempted at times to buy the 12-inch version.

The TI Shield is not going to kill the hum, because the hum is of mechanical not electrical origin, but you might find it benefits the sound and is definitely worth the effort. I ordered a 12 X 12" sheet and cut it in the shape of an LP, so it fits under my tt mat and does not show. For best results, it should be grounded to the tt chassis. If your platter is made of anything conductive, e.g., alu, that should take care of itself. Let me or let us know if the TI Shield cleans up the sound in surprising ways.

"Mercury" in flu vaccine
Sorry this is way OT, but it is one of my pet peeves.
There never ever was any "mercury" in any vaccine. In some vaccines, like inactivated influenza virus vaccine, there is and was thimerosal. Thimerosal is not free mercury. Thimerosal is an organic (carbon) compound which contains one atom of mercury per molecule in covalent linkage. The thimerosal is there to reduce the risk of bacterial contamination of the vial; it is basically an anti-septic. About 15 years ago, someone added up the amounts of all the thimerosal then contained in all childhood vaccines and discovered that it could exceed the safety limits for an infant. There was a furor in the US, and thimerosal was removed from all childhood vaccines very shortly thereafter. Currently, there is no thimerosal in influenza or any other vaccines given to children. There is still some thimerosal in multi-dose vials of flu vaccine(but not single dose vials) intended for adult use. Thimerosal intoxication is not linked to Alzheimer's or Parkinson's disease, except by hysterics, and anyway was never at issue with vaccines. The amount of thimerosal in vaccines where still in use in rare cases is (and always was) way way below even theoretically toxic amounts for adults and even for infants, except for the potential cumulative dose to infants as of about 1995, as noted. (No thimerosal now in any childhood vaccine at this time, to repeat.) Naturally, the anti-vaccine folks have seized upon this and other red-herring issues, as a reason for people not to get vaccinated. The long term consequences of not being vaccinated are negative for all of us (because of the loss of herd immunity against certain diseases). This is why we lately have outbreaks of polio, mumps, and measles in the developed world. People die from those diseases, sometimes children.

FWIW, my "other" LO7D (the one I still own), came with the Kenwood record weight. I do not like what it does at all. In fact, my experience with this weight parallels all my other experiences with record weights; they seem to take some "life" out of the sound. I realize that that sense of liveliness could also be called "distortion" due to LP resonance, etc, but it is a kind of distortion that brings me closer to the experience of real music played by live musicians.

I think I already wrote this, but I agree with others that the SAEC mat is excellent (now using it on my SP10 Mk3). I would not be inclined to mess with the stock mat on the LO7D, because I think it was carefully engineered for the turntable, but I do not like the typical rubber mats that came with Technics, Denon, etc. (I used the SAEC on my Denon DP80, also with good results.) Which is to say to Halcro that there are lighter weight metallic or graphite or other types of mats that I believe would outperform the stock rubber Victor mat, which in photos looks like the Denon rubber mat. You might try Boston Audio Mat 2, if you don't fancy the SAEC SS300. I have the deja vu feeling I have said this all before, more than once. Mats make a crazy big difference, IMO.

No one can assail Thuchan's stated preference based on his listening, but I tend to agree with Geoch; using the felt mat will certainly change the sound from that of the bare copper mat. However, if one does not like the bare copper mat, I believe the better cure would be to get rid of it in favor of a mat made of some other material. I am not sure that the impedance mismatch between a vinyl LP and copper is any worse than the impedance mismatch between felt and a vinyl LP. But that's the key, as Geoch says, IMO. Now Halcro mentions a pigskin mat on top of copper. That may be a completely different story vs felt. (Where the heck did you get a pigskin mat, Halcro?) I like the idea that the LP will probably not slip on pigskin, nor should the pigskin move against the surface of the platter. Also, the impedance of pigskin is likely quite different from that of felt, when matched with a metal like copper. I use the SAEC SS300 mat on my SP10. I have no idea what metal(s) its made of; I read once that it is an "alloy" of something. I tend to like it but I am open-minded about other materials that in principle may have merit, like graphite (or pigskin?).

I once owned a SOTA with a felt mat. Every turntable I have owned since then has sounded better to me in terms of ability to separate notes and musical lines and in bass definition particularly, so I am biased against felt, even though I think the main problem with the SOTA was a stretch-y belt.

Dear Halcro, Prompted by Geoch's posts above, I read up the thread from there and came to your post about the unusual behavior of your motor/platter with the 1.8kg M-S copper mat on it. What is the weight of your platter alone? If the weight of the Cu mat is a significant fraction of the total weight of the platter, what you are observing means to me that the brake mechanism of the TT101 simply cannot stop the platter "dead', because of the increased momentum of the platter/mat combo. This alone would not trouble me, but it could also mean that the servo system might be "confused" by the increased rotating mass during LP play, so at the micro level, the speed control with the copper mat might be subpar. It is a fact that these systems were designed as a whole; the servo is calibrated to the mass of the stock platter/mat. I have repeatedly mentioned this; super heavy mats on a direct drive might not be such a good idea for that reason. (And then if one adds one of those 4 or 5 kg record weights, one is making the situation worse and also inviting rapid bearing wear.) What I like about the SAEC SS300 metal mat is that it weighs about the same as the stock Technics rubber mat on the SP10 Mk2A and Mk3 (they use the exact same rubber mat), so screwing up the servo is not an issue.

"Whatever" means normal disturbances that occur in the typical playback setting, not f**king seismic events or dog accidents or children running into the tt or etc.

This has NOTHING to do with suspended turntables. Nothing nothing nothing. I don't like suspended turntables, as a rule. What you are thinking of is that in a suspended turntable the tonearm and bearing/platter MUST respond in unison, else you have all sorts of problems. But I am not in any way, shape, or form talking about suspended tt's per se. Are we clear?

It's hard enough to make the point without these exaggerations.

Dear Timeltel, You wrote, "the 71 lacks the reverse eddy current braking both the 81 and 101 implement in regulating overshoot incurred when correcting for speed". According to everything I have read and observed, that is not correct at least for the TT101. The TT101 is unique among 71, 81, 101, in that it has a reverse servo mechanism to correct for overshoot. Nowhere have I ever seen this described as eddy current based. I have no insight on whether or how the TT81 can slow down its platter. I do know that one sign that my TT101 is running as intended is that when I press the "stop" button, the platter comes to a dead halt. When I was having problems, the platter would stop but then rotate backwards for about half a turn before lazily stopping. This indicated to me that the reverse servo was not working properly.

Someone else suggested that Exclusive P3 and P3a did NOT have a coreless motor. My information says they both DID. (They were not really two different turntables; the way I hear it, there was a change in the way rumble was measured and Pioneer re-named the table from P3 to P3a so they could claim the new re-calculated lower number for rumble was associated with something they actually did to the table to improve it.)

Also, Denon tt's were said to have an "induction motor". That would be hard to do with a servo-controlled DD turntable; so far as I know the Denon DP80 has a 3-phase synchronous motor.

On the subject of "are we living dangerously", I would like to report to anyone who followed my travail with the TT101 on the "other" thread, where it was OT, that after my TT101 ran reliably for more than a week on our kitchen counter, I decided to spare my wife the sight of it and brought it down to my basement system, where I hope to use it. I plugged it in and turned on the Power, due to my (our?) conviction that keeping it powered on was advisable. I left it alone for about a week, because I was preoccupied with other issues. At that point, I tested the function again, ever the paranoid. Now the TT101 was malfunctioning again exactly as it had been doing previously: It starts up and runs for about 90 seconds. While running it displays speed errors, typically 33.32 or 33.34. Then it shuts itself down with no braking and the platter coasts to a stop. At this point, I have spent several hundred dollars with a machinist making alu parts to beef up the QL10 plinth, based on my previous confidence that the TT101 had healed itself. Out of curiosity, I moved the TT101 back up to our kitchen counter. In that locale, it malfunctioned for a while, just as it had done in the basement. However, within about a half hour, it had "healed" itself again, and now it is working perfectly, every time, on the kitchen counter. I am absolutely sure this problem is due to a poor electrical contact somewhere in the circuit, because the problem is associated with moving the unit around. I do not think this has anything to do with my basement or witchcraft. My plan is to take the top panel off and re-solder every contact on every switch. I am also concerned about the many multi-prong plugs that connect the various circuit boards. I don't know how to disassemble them in order to access the soldered joints within, but any one of them could be a culprit.

Thus I declare that the TT101 is the most "dangerous" vintage Japanese direct-drive tt of them all. I've never had any problems with any of the 5 or 6 others that I have owned that did not respond to the simple expedient of replacing the electrolytic capacitors.

Hi Gary,
I found your post of 9/16/13. I now know (once again) that your shield is made of mu metal and that the black stuff is auto interior material (which is exactly what it looks like). I probably also knew this 7 months ago, when you posted the info and photos originally, but the memory is fleeting. I found that same stuff on eBay that you have used. I Googled the eBay product, and there was some discussion that it is not as "good" as mu metal (it's a lot cheaper), but most conceded that it does work as a shield. I like your metaphor about squeezing a balloon, where you are describing what happens to the EMI when you installed the shield; the energy shows up elsewhere but not where you don't want it. Possibly, if you can ground the shield to the turntable, you would actually drain the energy to ground. But that may be tough to do.

I am going to get used to the sound of the TT101 with no shield, then install a shield, perhaps using the very same material you used, and see if I can hear a difference. I wonder whether some of the perceived benefits of those heavy copper platter mats are actually due to the shielding effect such mats have. If you read the verbal descriptions of the improvements in sonics, it certainly is consistent with the shielding effect.

Nice use of emoticons, Halcro. One emoticon is worth a thousand tears.
My TT101 is working, if I leave it powered up at all times, and if I don't move it, and if I run it at least once a week. With those stipulations, it's "reliable". I have heard it play music, but my new problem is that there appears to be a short within the UA7045 tonearm wiring, such that I have no right channel. I need to change the tonearm on the QL10 plinth. Interestingly, the Fidelity Research FR64S has a requisite spindle to pivot distance that is compatible with that of the UA7045, so I should be able to pop in my FR64S in place of the UA7045.
I will do that one of these days, when there is no other "project" in the way. Also, I am enjoying the Beveridge 2SW speaker system so much that I tend to want to listen to music when I do get free time.

Interestingly, if the TT101 gets balky, usually after I have not used it in a long time, the cure is to whack the (front) side of the plinth nearest to the control panel of the TT101, with the palm of my hand. Very unscientific but works a treat. I am very convinced that there is a bad switch or a loose connection between switches that is to blame for the finickiness of the table.

Ditto to what Pryso says. Downunder, you might consider finding another "tech". The guy you quote is not very tech-y. As Pryso says, the reason to change out the electrolytics has nothing at all to do with sonics (unless a leaky cap is causing a speed error already). It has everything to do with the fact that electrolytic capacitors have a finite lifespan. Which is to say that after about 30 years since most of our dd tt's were made, the lytics are near pooped. A leaky electrolytic (either electrically leaky, meaning that it can pass DC, or mechanically leaky, meaning there is goop all over the outside) can and will eventually take out an IC or a transistor that may be irreplaceable. Call it preventive maintenance, if you are having no problems. Like changing the oil in your auto engine at regular intervals. For a great tt like the Pioneer P3, do it.

Dear Halcro, Headshell offset angle does have an effect on the magnitude of the skating force, but it is not the prime cause. The prime cause is related to the fact that nearly all tonearms are mounted such that the stylus overhangs the spindle. Thus the cantilever/stylus can never be tangent to the groove. (You are fond of Copernicus; now think about that other Greek, Pythagorus.) Since the cantilever/stylus is not tangent to the groove, friction between the stylus tip and the groove wall creates a force at an angle to the path of the stylus; a component of this force vector is toward the spindle = skating force. A tonearm with no headshell offset angle is not free from skating force.

In medicine, it is said that a "specialist" is someone who knows more and more about less and less, until he knows everything about nothing.

Soft mats do have their appeal, but not soft rubber mats. Do you consider Delrin to be "soft"? I've never had one in my possession. TT Weights sells some, I think, and I've been tempted. However, I always thought of Delrin as one of those materials that attempts to mimic the characteristics of vinyl, so as to minimize impedance to energy transfer from the LP, i.e., I thought Delrin was "hard" (in the way that vinyl LPs are hard) vs soft.

Is there anyone here who adheres to the notion of elevating the LP in space, a la the old Transcriptors turntable platter and the new "Resomat"? It's the total opposite philosophically of what we've been discussing.

I have had a few weeks now to assess the effects of the Krebs mods on my SP10 Mk3. I was kind of a reluctant dragon going into this endeavor, because I was very happy with the Mk3 "as is" (now "as was"). When listening to the Mk3, I did not really perceive the kind of issues or colorations that were supposed to be "fixed" by the Krebs approach. This is in contrast to my experience with the SP10 Mk2, now departed. I could easily hear the "gray"-ish coloration that Richard perceives to be caused by an over-active servo (for want of a better way to describe it), when listening to my Mk2. In any case, you have to hear a modified Mk3 in order to know what you were missing. Richard's work makes the Mk3 more open and musical sounding, more of what HP used to call "continuousness". Based on this experience, I would suggest that the Krebs mod is also a no-brainer for the much more common Mk2. The cost is modest (especially for the Mk2 mod) compared to the benefits. Thanks, Richard.

I encouraged Richard to consider developing a modestly priced modification for the SL1200 servo and motor, since there are thousands of them in every day use. Apparently, he is already at work on that.

Doron,
I have always been curious about Joule OTLs, maybe because it's the only brand of OTL I've never owned or heard. I started with Futterman amplifiers in the 70s, owned many variants of the Futterman circuit, and now for the past 10-15 years have been using Atma-sphere amplifiers, as you can see. Most of my audio life has been OTL amplifiers driving ESLs. Lately, I've been enthralled by a pair of Beveridge 2SW speakers, driven of course by the built-in Beveridge amplifiers, which are not only OTL but also direct-drive. Amazingly good. The Bevs constitute a "second" system, in my basement. Atma-sphere/Sound Lab system is in my living room.

Well, I may now be the only one here who still does not have a completely reliable TT101. I can make mine work, but I would not say it is reliable, at all. I do have an idea of the problem and how to fix it, but I have too many projects, now including to complete the restoration of a 1959 Alfa Romeo Spider that's 95% done. To add insult to injury vis the TT101, its UA7045 tonearm seems to have a shorted wire somewhere inside. To use the TT101, I will now need to replace the tonearm on the QL10 plinth. Fortunately, the pivot to spindle distance for the UA7045 is close enough to that of the FR64S that I can sub the latter into the QL10. But since I love music more than tinkering, I tend to crank up the old reliable Lenco with Dynavector tonearm/Acutex LPM320 cartridge (muchas gracias, Raul), driving the Beveridge system via a Silvaweld phono stage and Klyne 6LX used as a linestage. The QL10 just sits there.

I personally use other peoples' opinions only in the grossest way, as a guide to what I might NOT like. Which is why I usually don't even ask. This is because my brain already knows what it wants, and I've already spent decades taking my brain to where it wants to be. I own a Lenco in a slate plinth with a "PTP" top plate (see Lenco Heaven). The OEM bearing is completely replaced by a "Jeremy" Superbearing (see also Lenco Heaven). The platter is stock, but it has been dampened. The idler wheel and idler arm are stock, but I have replaced a spring that loads the idler assembly with a lead weight on a string. This was the idea of Jean Nantais, possibly one of the Canadians to whom you refer. I have a Dynavector DV505 mounted on the slate. The AC comes from a Walker Precision Motor Controller. This combo gives me great pleasure, plenty of "air", dynamics, 3D-ness, whatever. It may be a hair less super accurate on timing, compared to my Technics SP10 Mk3 and Kenwood L07D, but if you don't compare it to those two every day, you don't worry about it or notice a problem. It definitely crushes the prior turntable, a Notts Hyperspace, in terms of timing, but I thought the Notts crushed the SOTA I owned before that, especially on piano music. You mentioned noise; I hear zero issues with noise, but again the Mk3 and the Kenwood (especially) may be a hair quieter. No idler noise that I can hear whilst sitting in my listening chair at normal (loud-ish) sound pressure levels. I think (very tentatively) that the slate plinth is superior to the Nantais plinth Lenco I owned prior to embarking on the slate project, less noise by a tad.

Sorry to all. I think I wrote much the same post only a few days ago up the page.

Pbn, My unit has been completely refurbished electronically. Even the very rare IC that runs everything has been replaced. (I found a source in Hong Kong.) However, we did not make an attempt to "upgrade" anything, except probably the diodes. It still has original transformer, etc. Can you go into more detail on how you "overhaul" the servo controller? (Sounds like you've been watching Chip Foose restore old cars.) Or should I contact you privately? (I tried to send an email to your website last night but could not find a way to do it.)

CT, The nice thing is, my Alfa does not have to be so reliable, as I will not be relying on it except for the occasional spin on local roads. But I do expect it will be more reliable than the TT101 has been so far. FWIW, I owned a Duetto for six years whilst living in NYC with no garage. It never failed me for one second during that time, through rain, snow, sleet, and parking outside.

Bulletin on the TT101. Long ago I had observed that mine works most reliably when the tach is set to "Run", where you see the speed go from zero to 33.33, over and over again. Since I had been getting cocky about its reliability, I set it to the "Hold" option the other day, just for masochistic reasons. I find that it's not so dead nuts reliable when the tach is set to Hold, as it has been on Run. This may be an indicator of where to look for bad solder joints or broken wires, but that's for another day, since it's fine on Run. I am mounting an FR64S and a Koetsu Urushi. Stay tuned.

Has anyone had any direct experience of the new PBN plinth-ed Denon tt's? The plinth is certainly beautiful and looks well designed.

Just be sure that the OEM thrust pad is suited to the silicon nitride ball. Bearing technology is complex.

Did you measure a "lowered sound floor", or is that a subjective judgement based on listening to LPs? These racing motor oils are designed to be used in engines turning several thousand RPM. I am surprised that one good oil would be noticeably superior to another good oil in a tt turning at most 45rpm. But on the other hand, Howard Stearn (L07D guru and surgeon, not the radio shock jock) swears by the Redline for the L07D, and nothing else, as you mentioned. So I guess I should not be surprised that for another table with a different bearing material a different (brand or viscosity?) motor oil might work better. My guess is a 5W-30 Redline would probably perform like the 5W-30 RP.

How do you access the bearing in your TT101? I can envision doing it either from above or below. Once you do that, have you had issues with the platter height? (I think you earlier reported that you did.) Thanks.

Banquo, Re platter rubbing. There was indeed one point in time where I perceived noise coming from what sounded like platter rubbing, only audible at 45 rpm, and I reported it here. However, the noise or rubbing sound, or whatever it was, disappeared as mysteriously as it had appeared in the first place, with no treatment or cure from me. There's been no issues since, and the TT101 is dead silent. Which is kind of why I am reluctant to lubricate the bearing, since that opens up a potential new can of worms. Nonetheless, I certainly agree that when Victor stated that the bearing would need no service "for the life of the turntable", they did not envision that a few old farts would be resurrecting them 35 years later.

Aigenga, Is it fair to say that the benefit of your IEC socket is the capacity to use "modern" power cords? It's the power cord itself that affords the real benefit. Where did you connect the third "ground" wire from your IEC plug to the chassis? I have done similar to vintage equipment, except I choose to dispense with the IEC interface. I just choose a suitable modern power cord, buy a length of it from Michael Percy, and then solder it directly to the power transformer. My favorite cord for this purpose is XLO; there are two types made by XLO, one more costly than the other, of course. Mainly they differ in wire gauge, but the conductors are of high quality, 3 wires, shielded, and in a head to head comparison with other boutique power cords, the XLO came out ahead (at least in my imagination). Kimber 8TC speaker cable also makes an excellent power cord (I'm using it on my Lenco), as does Goertz ribbon-type speaker wire, the heavy gauge version. My TT101 has to prove itself reliable enough to be worthy of this embellishment before I will go to the trouble.

Dear Thuchan, Dover and I are occasionally at odds, whereas I almost always agree with Fleib. However, in this instance, I disagree with Fleib, and I could not have stated the case any better than did Dover in his initial response. Obviously, a rigid relationship between the tonearm pivot and the platter bearing is a sine qua non for a suspended table, but it is also for me a "must" even in the absence of a suspension, and Dover said why. Like Totem said, this subject has been discussed ad nauseam. By now, those who will ever be convinced one way or the other have been convinced, or not.

I do think that a massive arm pod, such as the ones built by Halcro, linked rigidly to a massive cylindrical plinth (rather than standing on its own) would be a great way to go. Best of both worlds, you could say. Or, you could make the shelf part of the system by bolting the arm pod AND the plinth to a suitable shelf material.

Fleib, What are "DD motor vibrations"? In any decent DD motor, the platter either is the rotor or is securely bolted to the rotor. The stator surrounds the spindle. Thus the only source of vibration is bearing friction, which can afflict any type drive system. Cogging is also an issue for all types of drive systems. I hate to go into this yet again, but in theory one wants the tonearm and the tt bearing to be subject to the exact same external forces so they can respond in unison, resonate in the same way at the same frequency, etc, which should result in minimal dissociation between them in terms of energy dissipation. Thus the stylus is least disturbed from doing its job of following the groove. I'm convinced that this is the best way to go. I am not upset if others do not agree. This IS only a hobby after all. Not that music is not seriously important to me. Another way to say this: "Do what you want".

Truthfully, Thuchan, I think that the major flaw in the much loved Micro Seiki turntables are those cantilevered tonearm mounts. They are much too flimsy to achieve what I am talking about above. Once again, look at an L07D for comparison.

I don't know where the subject of a sub chassis came up in this discussion. Whatever you want to put under your tt should affect the tonearm and bearing/platter equally and simultaneously, is all I say. Yes, if you bolt the outboard pod to a shelf, and you also fix the tt base to the same shelf, you do get a semblance of the same effect I favor. Henry was not about to do that at the outset of this thread. I am not sure he espouses that approach even now.

You also wrote, "Cancelled? This is the mantra of the suspended. What external forces, sound pressure? You're just as likely to increase consequences, as cancel. Extraneous vibrations should be dissipated, not perpetuated."

OK. Whatever happens to the tonearm, from whatever source of spurious energy of any kind at all, should also "happen" to the platter/bearing at the same point in time. You can choose whatever base you want, whatever source of spurious energy you want. I don't like suspended tables for other reasons. I think we're talking past each other. But I see you disagree, and that's fine. Thuchan asked for opinions, and I am certainly not alone in mine.

Sorry, Dover. I was cranky that day.

For me, there's no perfect way to measure the phenomenon we are trying to understand, so I prefer listening tests.  Listening tests are inevitably subjective in nature.  However, lately I have been doing a lot of listening to my SP10 Mk3 as the Krebs mods "break in".  Richard originally suggested it would take some time, and I was skeptical.  However, now I must report that the Mk3 is "smoother", more "continuous" in sound by a noticeable amount, compared to pre-Krebsian era.  Furthermore, these virtues are attended by a new open-ness of the sound; the sound is freer of the turntable than before.  I would liken that difference to what I heard when I changed from a belt-drive with a conventional plinth to one with a plinth that resides only under the platter, a la Galibier or my old Notts Hyperspace or the plinths favored by Halcro.  Adding these new virtues to the rock solid timekeeping of the Mk3, and I cannot imagine anything much better. (Of course, the "timekeeping" should be better than OEM due to the effect of the Krebs mods to reduce the number of servo error corrections needed per unit of time.)

Dover, It has long been my observation that your major goal in participating in this discussion is to "prove" by the force of insistence that your particular Final Audio turntable is "the best".  Secondary goals are to prove that the finest direct drive turntables are inferior to the finest, most expensive belt drive turntables.  You've made these points over and over again, never with any sort of "science", except for the implication that what you hear and report is to be taken as gospel.  So, I hardly think it behooves you to come down on Richard for not offering "proof".  Actually, Bill Thalmann may have made some measurements of Krebs-modded SP10s that do support the claims.  I will inquire.

It is irrelevant to me that you place no value in my subjective judgement, so we are even, so far as that is concerned. What I wrote about the Krebs mod was meant for persons who use SP10s.  Direct drive has its issues, and so does belt drive.  Apparently you prefer belt creep and speed instability to issues related to servo mechanisms.  That's fine with me.  And by the way, if your Final Audio has a motor controller drive system of some kind, the chances are that it too has an error-sensing mechanism which has the potential to produce an effect not unlike that of a DD servo.  The only difference in the case of a belt drive is that the corrections are delivered via pulling on a compliant belt, which has its own pros and cons. Playing LPs is an exercise in inexactitude; each of us must find his own set of likes and dislikes which in the end must be based on listening.  What I don't understand is why you hang around here, if the subject of this thread is so odious to you.

Henry, I think you meant "moot".  The new SL1200 is very intriguing in that it seems to use a coreless motor, rather than the typical Technics iron core motor. (All Technics DDs, from the SL1200 to the SP10 Mk3, used iron core motors, albeit the one in the Mk3 bears faint resemblance to that which was used in the original SL1200, in terms of torque and the number of poles [24, in the Mk3], which would tend to reduce cogging.)  The new motor would represent a potential significant improvement with respect to the old SL1200.  Thus I wondered why (1) they are using the identical nomenclature for this new product ["SL1200"], and (2) they built it to look JUST like an original SL1200, as well.  Since the price will be much higher than that of the original SL1200, even adjusting for inflation, this may or may not prove to have been a marketing error.  Nevertheless, I am intrigued (because of the coreless motor), but I don't think this thing will blow away what we already own.

And Dover, you probably should consider changing the electrolytics in the drive system of your Final Audio TT.  Forty years is challenging the upper limit of electrolytic life, albeit if you indeed do use it "every day", that would tend to prolong their lifespan.  I don't see any reason why you should fear that doing so would in any way negatively affect TT performance; in fact, if any of the originals are leaky, it would improve performance.

Fleib, While you are thinking of copying the material used by Kenwood, note also that they never used an outboard pod; their engineers saw the value in firmly coupling the tonearm mount to the tt bearing assembly and motor.  Mimicking their approach with your TT81 chassis is going to be difficult, but you could at least approximate it.

Fleib, The debate between Halcro and I was never ending and fruitless, so I abandoned it, probably to the relief of several.  I would submit that you WANT the tonearm and bearing to be equally affected by outside disturbances of all kinds, so as to perturb the one with respect to the other as little as possible whilst the stylus, which is physically at one with the pivot of the tonearm does its business of tracing the groove, which is physically at one with the platter and bearing.  That's my story, and I am sticking to it, along with a myriad of professionals in the business of designing, building, and selling turntables.

My thought experiment, which was mocked at the time by Halcro, is to imagine that you have to perform a delicate operation in a rowboat that is floating in the sea.  Would it be easier to work accurately, if you have your project in the boat with you, such that the rocking of the boat will affect both you and your project equally and simultaneously, or in another boat floating independently beside you?

Guys, Do what you want.  I'll love you anyway, even Halcro.  By the way, I have never tried jumping off my roof, but I have a fairly strong hypothesis regarding the outcome of doing so and therefore, I won't try it.  (That's an exaggeration of course; I do not regard using an outboard arm pod with the same skepticism and dread that I view the idea of jumping off my roof.  And I totally agree with Halcro, if you do it, use as massive an arm pod as is practical, along with a massive plinth.  If you do it that way, the difference between my preference and Halcro's is minimal.) Anyway, who said I never owned a tt with an outboard arm pod?

You certainly could be correct on the TT801. I read that blurb on Vintage Knob too, earlier today.  The TT801 wouldn't interest me purely for the vacuum hold-down, but the idea that it might be different from the TT101 in other ways, most notably because it has a higher mass platter, is quite interesting.

Chakster, The TT801 incorporates a platter that is perforated and lined with a rubber gasket to facilitate vacuum hold-down.  To generate the vacuum, you also got a pump housed in a separate external (large) wood-veneered chassis.  Like Halcro said above, the problem these days is that by now the gasket usually has deteriorated; the rubber used was not up to modern standards.  Yet, the TT801 seems to sell for a huge premium over the TT101 and TT81, in the Far East.  They are rare. Whether the basic table is akin to a TT101 or TT81, I am not sure.  I used to think it was a hot-rod TT101, but since Halcro says the TT801 lacks the stepped speed control found on the TT101, perhaps it is more like a TT81, plus vacuum platter.

rwwear, I almost giggled when I read your statement that you might prefer the TT101 to the TT801, because the former is "more easily serviced".  Indeed, if there is a more complex and difficult to service DD mechanism in the world than that of the TT101, I would say stay away from it.  As to your contention that the vacuum was an option with the TT801, can you document that?  Or do you mean to say that a TT801 with no vacuum hold-down is a TT101, which is what I have believed before this specific discussion?

I did have some heartening news today.  I sent a TT101-specific Integrated Circuit chip to a fellow enthusiast in Germany for repair of his own TT101, and he informed me that my chip worked to salvage his unit.  He is very pleased, and so am I, as the owner of a TT101 that currently is only good for a boat anchor.  Where there's life, there's hope (realizing that this is hardly a matter of life and death).

Thanks, Henry.  In fact, I did not "corner the market" on the Integrated Circuit needed to run the TT101.  I bought only several of them, but probably could have bought 100.  I found them a few years ago from a Hong Kong or mainland China vendor simply by googling the part number written on the back of the chip itself.  I don't see why one could not still do the same.  Most such vendors are on Alibaba.  I gave two chips to Thuchan, since neither he nor I knew for sure that the chips I received were authentic (in other words, not mislabeled as to part number) and in good working order.  Turns out they are indeed correct as to type and functional.  (Evidently, the first one of the two did the trick, so I assume the second one is good also.) Now I am thinking about sending my TT101 to Thuchan's guy.  I've got THE chip for the Denon DP80, too, but no extras I can afford to sell or give away.  I want to keep one extra for my own DP80, which is already running on a new one.  I did not mention names above, because I was not sure Thuchan wanted to go public.