Vintage DD turntables. Are we living dangerously?

I have just acquired a 32 year old JVC/Victor TT-101 DD turntable after having its lesser brother, the TT-81 for the last year.
This is one of the great DD designs made at a time when the giant Japanese electronics companies like Technics, Denon, JVC/Victor and Pioneer could pour millions of dollars into 'flagship' models to 'enhance' their lower range models which often sold in the millions.
Because of their complexity however.......if they are 'unobtanium'....and they often cannot be repaired.
Here is an image of the innards of a TT-101
and here is one of the TT-81
As you can see.....the TT-101 is considerable more complex.
Imagine trying to work on that if something goes wrong? :-)
Here is a posting from a couple of years ago from AudioKarma I think which explains the problems we, who own such exotica face:-
"I had an interesting conversation today with Tommy Cheuk, the owner of "Top Class Audio" here in Hong Kong. Some of you may know of him and his shop via the website; Tommy has been enjoying and selling hi-fi gear for many years, and has some of the finest stuff (especially turntables), to be found anywhere, period. If you are into turntables (tonearms, carts, step-up transformers and phono pres, etc...) his shop is a must-see mini-museum where all the nice rarities are for sale, albeit at often painful prices.

Because he often gets very rare stuff from Japan that I don't see elsewhere, I went by his shop to ask about accessories for my GT-2000. He commented that ever since a "club" had formed in Japan centered around this model, the prices of the accessories had been climbing steeply, with some Japanese even buying back and re-importing the TTs and accessories that made it elsewhere (like Hong Kong)! He said this --and the escalating prices-- was why you almost never saw them any more locally. [His words re-confirmed my feeling that I really did get a lucky bargain with mine! ] He said it was even worse for Hong Kong (and American) buyers now, due to the currency valuations. So these days he doesn't have any stock of GT-2000 stuff. Not good news for me, but I can live with it. I know I'll still get the things I want, from Japan, although some won't exactly be cheap.

While we were talking, another man came in looking for a Technics SP-10 or SP-12 Mk II or MK III (I forget which), and Tommy said that he no longer carried them! This surprised me, because I remember seeing several pass through his shop within the last year or two. To my surprise, he said he had stopped carrying them recently because the critical motor- and speed-control ICs were no longer available [i.e., they have become --HORRORS!-- "unobtanium"], so once these parts break down, the TTs cannot be repaired. He explained that this was increasingly true for several of the best models of direct drive TTs, so he been forced to stop dealing in, for example, the TOTL Victor (JVC) TT-801 and TT-101 models. He (Tommy) had personally had a 101 as his main player at home for over ten years, and then bought a beat-up "spare" for parts, but in the end had to throw both of them out, when the pitch/speed control ICs went bad. [He still has one in his shop, with three tonearms I drooled over, pictured here: ]

I asked if he could have found chips elsewhere, and he said no doubt there were still a few here and there around the world, but finding them was another story. Since these models were only sold domestically in Japan, there were never large stocks of parts overseas, and all the usual channels (authorized dealers and repair outlets) in Japan were 100% out-of-stock.

"Ditto" for several of the Denon direct-drive models.

What is worse, is that many of these chips are 96-prong (or something like that) devices with rows of connectors on all four sides, that require special "factory" desoldering tools to remove or install. In some cases, they were installed by these machines directly into surface-mount type boards, and the customary repair was to replace the entire board, because there is no way to safely remove the chip without damaging it. There are no more replacement boards for a good number of the models, and those that are left, are dwindling in number.

All the other components, such as resistors, capacitors, etc... are replaceable, and the TTs can be maintained for a long time, UNTIL either of those two critical IC chips go. When that happens, if there are still replacement chip stocks available, AND you can find someone (usually only the factory or their agents) who have the correct gear or replace it, OR if you can find a whole replacement circuit board (sometimes a necessity, sometimes just an option), then you can keep listening to your TT. But if the chips are gone, you have a beautiful doorstop...

He suggested that anyone owning any of the better 80s-era Japanese direct drives faces this problem sooner or later, and for some of the nicest models (those I mentioned above), the clock has essentially run out already, but on the good side, he said the best solution he knows of is to PLAY THEM OFTEN! Playing them frequently offers the best possibility to prolong their lives, especially in a humid climate like Hong Kong's.

Well, at least there was ONE good note (pun intended) in this rather depressing conversation!

We discussed the Rockport Sirius III that is sitting, unused and unplugged, in the corner of another showroom in the district. The people there say they know there is electronic circuitry inside which they don't want to "wear out", which is why they don't play it. I've suggested to them that playing it might be better than not playing it, but they seem not to believe it. Tommy chuckled and suggested that perhaps the thing had died BEFORE they unplugged it, and this is their face-saving excuse for not using it? I've heard that suggested by one other person before, so perhaps there is some truth to it(?).

I'm thinking now about strategies for trying to get and stockpile replacement parts/chips (if they are the replaceable kind)/boards for my DD TTs. For the GT-2000, I suppose buying a spare TT would be one approach, albeit an expensive one. I also have to find out what kind of chips are in the PL-L1, and if they can be found. Hopefully the same kind as in the later PL-L1000, as I'm sure if they were exclusive to the PL-L1, then they are basically unobtanium, by now. Even finding Pl-L1000 parts won't be too easy. And then there is the Sansui SR-929... And the Pioneer PL-C590. Hhhmmm, I suddenly feel a wee bit less confident in my collection of direct drive TTs!

Hope this didn't rain on the parades of any DD owners here. With careful maintenance (replace those aging caps and check the other stuff every decade or so, folks!), they may yet last for many more years, even decades. But once either of those critical two chips goes, cross your fingers that they are still available, or else you just became the owner of a very fancy doorstop!

Oh, and in case you think he had some commercial reason for saying all this, NO, he praises their absolute speed stability and great sound (as I said, he used them himself for years at home) and has sold the better Japanese DD tables alongside the better belt drives (incidentally, he had a couple of magnificent Micro Seiki thread drives there, one 1500 with gunmetal platter, another limited edition with gold-gilt platter) alongside other TOTL tables, including some DDs. No, I believe he was telling the sad truth. A truth I suppose we all know back in the deep recesses of the mind, but hate to have stated to our faces. The fact that he threw away two of Victor's all-time-best turntables because he was sure there was NO way to repair them any more... well, it just sickens me!

I think I'll start taking his advice, and playing MORE vinyl, to make sure all my DD TTs get enough of a workout to live longer! Maybe it will take my mind off of this train of thought.

Of course, I would probably last longer, too, with a little more exercise... "

Now if you own a vintage belt-drive or face no such problems.
They are both readily fixed with parts available and no such reliance on electronics.
But great Direct Drives offer a speed accuracy and coherence which other drives can only dream I guess we just live for the moment.....enjoy them whilst we can.......and hope for the best?
After all.......those that still work have lasted over 30 years now. What's another 30 for Japanese technology? :-)
Couldn't't sleep last night Hal? :)
Wow, looks like an electronic pizza with the works....:-)
I just got into another Japanese DD table you haven't mentioned the Yamaha PX-2, which seems a cross between an SP-10 MKII and a Bang and Olufsen 8002. It sounds great, but with the linear tracking arm, on top of the direct drive, it is the very definition of complicated.

sounds great, but getting it serviced, or upgraded, is going to be difficult.
Damn what a story.

For myself I definitely feel I'm living dangerously with my DD turntable. I have a Concept 2QD TT that has a busted foot but other than that it works really well right now. The company that made this TT went out of business a long time ago and parts I believe are scarce. I was a little overzealous about the table and I overpaid for it. If something were to go wrong it would be expensive to repair and I'd be reluctant to pay for the repairs. So while I'm enjoying the music whenever I play the 2QD now I'm keeping my fingers crossed it will survive as I save up funds for a less complicated TT. If it were to break down I'd sell it for parts.
Dear Halcro
I have bought a few items from Top Class in the past and I don't ever remember not seeing any various brands of direct drive tables that weren't up for sale.

The poster from Audiokarma is certainly correct about one thing that Tommy usually has in stock at any given time a collection of ultra rare tables.

To ease your paranoia, if your 101 proves to be a stellar performer above what you currently have, buy a second one.
Dear Henry,
Most of the contents of the long passage you quoted are utter hogwash. (1) Because the TT101 looks complex to the uneducated, like you and me, is no reason to believe it cannot be worked on by a trained professional. It is not voodoo. (2) The very same chip for the SP10s is also used in a wide variety of later production versions of the Technics SL tt's, e.g., SL1500, SL1600, etc. There are thousands of those tt's around,and one can buy them cheaply, if one really needs the chip for one's much more valuable SP10. A certain SP10 aficionado from Texas has done that more than once. Moreover, if you renew the electrolytic capacitors in your SP10 before the chip gets blown, the problem will not arise. (3) I have a Denon DP80 that came to me with a partially defective IC. I was told the part was unobtainium, as you suggest. I took the part number off the chip and did a Google search. I found at least a dozen small electronics houses mostly in Hong Kong that had a supply of the needed Denon chip. (Mind you, this chip was made only up to 1983 and only for the Denon tts, so my results were quite amazing.) I acquired not only an NOS chip for my tt but two extra ones, for less than $25, and there were offers to sell that went as low as a couple of bucks. (I actually paid too much but went with the guy who wrote the most coherent English.) It seems there are thousands of those chips out there. The only problem is that those few who need them don't know how to find them or don't try because they believe they will be unsuccessful. (4) In general, in many cases where discrete transistor parts are no longer available it is because the part has been replaced by one that is functionally superior. Bill Thalmann (one of those "trained professionals") also replaced all the transistors in my DP80, not because any were bad but because Bill knew that the newer part was superior and more reliable and would improve the function of the tt.

So, don't panic or cause the rest of us to panic. You know what is really unobtainium?.... a 1957 Ferrari Testa Rossa.

By the way, I will gladly take a TT101 off anyone's hands, to allay fears that it will fail and can't be fixed.
Yes you are!!
This is an interesting thread in that I had planned to send Halcro a PM asking who he was sending his DDs to for repair.

I once did a global search for 2SK147 (a low noise FET). At the time they were, as Lewm said, available if you searched for them. The hitch was that you had to buy industrial quanties, minimum of 100 pieces (IIRC), at whatever price being asked. In fact, there are companies who specialize in finding and stockpiling obsolete chips.

That said, I have seen techs with amazing knowledge, skill and training, struggle for months trying to fix audio esoterica from the Japan Inc heyday. So, just because we are not electronics experts, that doesnt mean repairs on such gear is necessarily simple or easy for the expert.

One thing we might do is get together and identify a tech that has the skill to fix and keep these pieces running - and then give him our buisness. Sure the original chips might die but their final function is generic. Perhaps a such a clever tech can often design a circuit to replace the dead chip from the signal and PS input to that chip to where the dead chip rejoins the circuit.
Dear Halcro, There is nothing as cruel as the thruth.No wonder only a small part of the human kind pretend to be interested in the real truth: the scientist. I want mention the assumptions about the spead of light and their reaction about possible refutation of Einstein. Refusing to except anything else is some evidence of the mentioned 'pretending'. Why do you want to scare us? From the other thread in which you are also involved it follows that there are no good TT's whatever. I was not able to comprehend the arguments but well to understand the conclusion. My only consolation is the fact that I never bought those astronomic expensive plinths nor the similary expensive TT.

Dear Lew, There is one Victor TT 101 on the German ebay for
1000 Euro and if you like to prove that you are right you
are welcome to try. Halcro warned me just in time to avoid
my temptation.

I have to agree with Lewm on this one. I made my living for decades servicing all sorts of audio gear. I would regard it as highly unusual to see a chip failure!!

That is worth repeating: I would regard it as **highly unusual** to see a chip failure!!

Usually you see dirty switches and controls that result in poor speed regulation, electrolytic caps failing- that sort of thing.

So I would see an explanation like this as a bid for a lower price on a prospect.

Now, if you live in a tropical environment, the chips are in a little more danger, from corrosion. If you want some simple protection, you can 'pot' the chips with silicon sealer, the clear kind similar to aquarium sealer. I should point out though that in tropical environments the circuit boards in general are in great danger, so usually you have other concerns that far outweigh the chips... In non-tropical environments this is probably not an issue.

These days I do far less servicing than I used to, but I still maintain my own vintage analog synthesizers that I play in my band. They use a lot of unobtainium chips too! I would say the major force that causes the price of such ICs to rise on eBay is mis-diagnosis of other problems in the synth (usually bad connectors and electrolytics)! I see it all the time....

Dear ´┐ŻNandric, 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:

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.
Dear Lew, I am not a brave man and have no intention whatever to prove enything. This peculiar TT 101 was already bought and returned to the seller by Halcro. I would never dream to prove Halcro wrong in enything. But I thought that you wanted to prove something so this info about German ebay was meant for you. Ie I am willing to buy the thing for you but this would be an unnecessary
postage complication: from Hong Kong to Holland and than
from Holland to the USA. You can buy the thing directly by
the seller in Hong Kong (Foxtan or so).
However I need to mention that I just got from Moldova
( no typo) the plinth for my SP 10 MK II. For $ 180 all included. With 4 leayers of MDF and black spray. The problem however is I have no idea what to do with this TT.
No place in my living room for a second TT and my bedroom
is already occupied with some other stuff.

Dear Nandric, I read a little about the new data that call into question the actual speed of light. Compared to other previously existing data that confirm the Theory of Special Relativity, I think the data from CERN are rather weaker. I am going with Albert on this one.
Relatively speaking, dealing with any vintage gear is riskier than dealing with new.

Value may be more as a collectable to a very narrow market than anything else with old stuff, no matter how good it is.

But, where there is a will, there is usually a way. You just have to be dedicated enough to find it.

I would personally take a chance on a vintage DD turntable perhaps but only if I were to find a very good deal. I am not a dabbler anymore when it comes to turntables.
If Lewm is right, then Mr. Cheuk should terribly regret "throwing out" two (!) TT-101s.

Incidentally, his site presently has one for sale for anyone who likes to live dangerously. [I have no connection to that site or the owner]
Lewm is 100 % correct, also TopClass currently has more then one Victor 101 up for sale along with Pioneer Exclusive including other DDs.

The story at Audiokarma is just that, a story.
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.
I have no doubt that Lewm is right regarding the vintage Technics and Denons. But the Victors may present a different proposition since there weren't as many made and it's unclear, to me at least, that subsequent JVC/Victor tables can be cannibalized for parts in the way that the later Technics can. Either way, buying a DD presents a risk that buying an idler doesn't: the latter's parts can be machined brand new should the need arise. Having said that, Thalmann is THE MAN and I'd have faith that he can fix what ails any DD turntable.

But perhaps we shouldn't let Mr. Cheuk in on it since he'd likely raise his prices on these stellar pieces. :)
Couldn't't sleep last night Hal? :)
Heh heh :^)
Wow, looks like an electronic pizza with the works....:-)
A good description Rockitman!
Thanks for all the responses.
Lew.....does the SP10MkIII look as complex inside as the TT-101?
What occurred to me is that all that electronic complexity is probably a late 70s attempt at a 'computer'?
Today, it all could be accomplished by one tiny chip? That's probably how the new DD NVS turntable does it?
Why wouldn't other manufacturers revert to computer controlled DD I wonder? Kinda like emulating the success of the great Japanese ones of the past?

Hi Halcro. The bottom cover on the JVC is rather flimsy. I owned QL7 and QL-A7 before so I know they are not very rigid. I noticed you placed 3 footers right below that bottom cover. I know you like the nude style and no-plinth approach. Would it be better to have maybe some cylindrical footers, literally almost foot long, that support the chassis where the motor is directly mounted on? This way it can still qualified as "nude" and you eliminate that wobbly sheet metal and adds rigidity. Might be worth a try. I sold all my QL-7s so I can't experiment anymore. But I would like to know what you think.

I am a JVC fan but I came to the conclusion that I only like the ones that use coreless motor and QL-7 and QL-8 use core motor but the 101 is coreless and it's their top of the line and I am salivating here.... I would love to hear it compare to, say, a Kenwood L-07D, another coreless masterpiece.

Have fun!

Yes you are !
You're right Hiho about the flimsy bottom cover to both the TT-81 and TT-101 and when I tried to support the TT on the three spikes positioned inboard of the edges.......the table was able to be rocked by grabbing the outer edges and twisting.
However when I moved the cones so that their centerlines coincided with the centreline of the vertical edge of the cover (in other words.....the cones half protruded from the bottom edge)......I could induce no movement whatsoever. No wracking, no twisting......utter stability :^)
I think both you and Lew are correct about the advantages of core-less motors which both the TT-81 and TT-101 share.
The interesting thing was that the 81 and 101 share everything in terms of construction, motor, platter etc and the only ostensible difference is in speed detection and correction with the TT-101 having double bi-directional monitoring and correction.
When I slid the 101 into the same place as the 81..... The difference in sound was astonishing?
If you click my 'Systems' page you can read a treatise I posted there by Peter Moncreif who maintains that accurate instantaneous speed control is the fundamental role of the TT.
So it would be interesting to know what the speed detection and correction abilities of the Kenwood and the SP10 are? Perhaps that's where the heavy platter and high torque motor of the Technics come to the fore?
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.

This is what I was alluding to in the synth world- its a bid, based on fear, for a higher price- maybe for the cost of repair (replacing an 'expensive' chip that you don't have to replace, but get to make money on), being unwilling to admit to not being able to repair the unit, that sort of thing.

Bottom line is chip failure is the least of your concerns! They literally will be the least likely thing to fail.
Thanks Lewm. MY SP10s are rebuilt by Bill and at the time he informed me that the chips were also used in thousands of less expensive tables. I have no reason to doubt him and I've never seen a table this easy to live with that also outperforms anything else I've come across. I expect to pass my MKllls on to my children(assuming they want them).
Thanks guys.........particularly Lew and Ralph.
I did sleep better last night :^)
One Brought up to Spec Technics Sp10MkII - $1000

4 - 5 Inch high - One inch thick Stainless Steel Machined Legs - $48

One 5.2 inch high 4 " diameter solid Brass Arm Pod (Over 19 lbs) $200

Sound that competes with the big boys - priceless

For this kind of money and sonic enjoyment I will take my chances. thank you

FWIW - I had many discussions with the chap I bought my second SP10 MKII from. He has many of the them and other brands as well. When repairing and bringing them up to speed I remember him saying he replaces electronic parts with better ones if they are obselete. A mechanical problem with the motor itself would be a problem.

As Sonofjim said I expect mine to be passed on to my kids as well but in my case I don't think my kids will want them. They are 17 now and part of the convenience and portability generation. They dont need a dedicated room for their music.

Dear Banquo, What I did point out is that the service manual of the TT101 is available on Vinyl Engine. With the service manual, a competent person can trace a problem to its source. That is the first step in the repair process. As to its possibly unobtainable chips, I would bet that like the ones we know about (Technics and Denon), Victor also used a family of parts that is common to several of their designs in that lineage. It might be a little more difficult to obtain the donor tt, for the Victor family, since so few of the best ones were exported, but it could be done, I would be bet. And then too we have the internet as an unprecedented way to find odd parts that our local distributor might say is "unobtainable". I would not be the least bit afraid to own a TT101, except I would prefer a TT801. Isn't that the very top of the line? Or is the TT101 uber?

Yes, after listening to my L07D, I suspect there is magic in coreless motors. Note that Brinkmann has chosen to use a coreless motor in its direct drive renaissance. But one can hardly make a firm conclusion based on one sampling, and I am sure motors with an iron core can sound great to. To wit, the SP10 Mk3. I have no idea about the NVS motor type or its speed control mechanism, except I think I read that they have eschewed the use of a servo.
I too have a JVC TT101 and a JVC TT81. I really enjoy these tables, they are both mounted in identical original plinths.

At this moment my TT101 is out for recapping and contact cleaning at a local (Brooklyn, NY) pro audio repair shop -

I might have waited too long to get it recapped as a warm up suddenly became necessary to achieve speed stability. Needless to say I am nervous about getting my baby back and running well.

I am using the TT81 at this time and it is fine, but it ain't the same - as Halcro has so beautifully written. My wife - who only comes in and listens from time to time commented that the sound wasn't as good at this time: and the only thing that changed was the the TT substitution.

Part 2 follows
Speaking of my TT101 and TT81:
I use aurios and still points in combination (creating three feet - two in back and one in front) to support the plinth, I also have a squash ball under the sheet metal motor cover - that ball is absolutely required to damp this ringing metal bowl.
I am very interested in Halcro's finding that when he compared so many amazing tables, that I don't believe I will ever have a chance to listen to, the TT101 was a top runner. I feel rather lucky that I ended up with such a seriously good machine, that is if I get it back in one working piece.

Now that these machines with their sealed bearings are in their 30's I am thinking it may be time to clean the bearings and most likely change the oil. Does anyone have any information on getting into these sealed bearings?
Dear Aigenga,
My 'Brother' :-)
How fortunate we both are to have these tables?
Don't worry about cleaning the bearings and changing the oil.......there is no oil and the bearings need no maintenance.
At least that's what the Service Manual says.
You can download both of these on Vinyl Engine.
I hope your tech knows what he's doing and does a good job?
It will be interesting to hear your reports back?
Please keep us informed :-)
The TT-81 and TT-71 use the same CORE motor. The 81 uses more sophisticated electronic drive than the 71.

Now, the TT-101 is a completely different beast. It uses a CORELESS motor and a "double bi-directional servo" in the electronics. So it is no surprise that Aigenga prefers the 101 over the 81. I have no experience with the 81 nor 101 but I have owned other JVC models and every time I prefer the ones with the coreless motor and even my non-audiophile friends noticed the coreless tables sound "smoother." It has a distinctive fluidity in the sound that's recognizable. I would LOVE to hear a TT-101.

Much information can be found at the invaluable The Vintage Knob site.

Hiho, FWIW, that's the first thing I noticed once I got my L07D up and running, an uncanny sense of "fluidity" (good word for what I hear), plus the L07D's signal to noise ratio seems to be unusually low, which adds to that same sense. The turntable gets out of the way, and the music is just "there".
An update on the recapping of my TT-101. I just spoke with the tech and he says that he will only be changing out the caps in the power supply section, not all of the small ones on the regulation boards. His take is that the large ones should be changed from time to time but the tiny ones will not cause any problems.
Anybody have a point of view on that?
Aigenga, I can tell you this: the main thing that causes speed stability problems is not bad caps but dirty speed selection switches and dirty speed controls. So if you have a variable speed feature this is the first place to look.

Radio Shack makes an excellent contact cleaner that is about as strong as you would want to put on any audio components. A quick shot of that stuff, and work the control back and forth, and its likely that speed stability is restored.

BTW, some machines that lack an external control may well still have an internal control. Figuring out which one it is and cleaning it is a slightly more complex task. At any rate I would not worry about on-board caps so much as I would filter caps in the power supply!

Occasionally certain parts get identified as trouble makers. I've seen a lot of tantalum electrolytics short out over the years. These days if I see them I don't trust them no matter where they are.
"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.
A belated response to Henry's question about the complexity of the SP10 Mk3 vs the TT101: There are no on-board electronics in the Mk3 save for the on/off and speed selector switches and wiring thereto and the brake solenoid. All the electronics are housed in the outboard power supply, which is much larger and heavier than that of an SP10 Mk2, for that reason. This arrangement allowed Technics to build the chassis proper such that resonances are minimized. (No hollow cavity or thin-walled structures, etc) And I reckon it also allowed more room on board for the humongous motor. As to what's inside the Mk3 power supply, I deemed it to be so "special" that I did not want to mess around inside it. (As you may know, my Mk3 was acquired in NOS condition.) I simply handed it to Bill Thalmann and let him do the work. Ergo, I don't know what it looks like inside. But the schematic is available on VE.
Thanks for that information Hiho.
I didn't appreciate that the TT-81 didn't have a coreless motor?
Can anyone explain the advantages of one over the other?
Are there still 24 poles so that there are 24 impulses every revolution?

Its worth the risk IMO. Firstly, the depreciation on a vintage TT is way, way less than on a new belt drive TT. You also get a piece of history as well as a functional HiFi component .

Going through life in fear of something breaking down is no way to exist. Look at the stats - chances are things won't go wrong anyway, so why choose to fret about it? You can always buy a spare if you really cant sleep at night.

Long term the vintage DD will be cheaper. Many high end belt drive TT's I can think of have an uber expensive upgrade path that give you the feeling you are missing out unless you keep spending. Not so with some of the substantial and dare I say majestic DD turntables ( in terms of engineering and appearance).

This may not be an advantage for everyone but chances are the wife can probably handle a vintage DD TT more so than the less ergonomic belt drives. And both of you don't need to go cross-eyed every night trying to take a reading from a strobe disc........
I am using a thin sorbothane sheet against the platter, topped with a thick achromat and a brass center weight. How are you dressing the platter?

Also, I am considering an outer ring, but am worried about how the extra weight will effect the motor and speed control.

I am picking up the TT101 tomorrow, fingers crossed.
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.
PS. Yes, coreless = slotless. Just found a site that confirmed my impression. And coreless motors do not exhibit cogging.
As far as the sound difference between the TT81 and the TT101 I would have to say it is more of a feeling difference, I am more relaxed with the 101 - no gritting my teeth or other tensions. The feeling is that the music flows better and is more easily pulled into me. Words fail me.
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.
I'm currently using the excellent Victor rubber mat which comes with the TT-101 (note that this is slightly different to the one which comes with the TT-81).
I find that these 'ringing' platters cry out for the damping abilities of these mats as I believe Victor also realised and perfected?
On top of this I place the suede (pigskin) mat made by Victor especially for these tables. These are available form Tommy at TopClass for $130.
I tried the Millenium carbon fibre mat directly on the aluminium platter which was not as good and also tried it on top of the rubber mat which was not bad....but the above combination I settled on works well for me at the moment.
I'm tempted to try the heavy 1Kg+ gunmetal Micro Seiki mats but the costs ($1000-$2000) make it too risky for me?
Oh and please don't spend any money on an outer ring unless you use it with an undamped metal platter.
Here is a thread precisely about my findings on these
Doesn't it seem odd....if a coreless DC motor produces no cogging and sounds so 'fluid', relaxed and unfazed.....that a manufacturer would be foolish to even contemplate an alternative design?
I mean is the price difference between the two types hundreds of dollars?
I wouldn't imagine so?
Henry, On that last post, one would have to peer into the brain of a Victor engineer to find out why all Victor tts were not equipped with coreless motors. The motor in the TT101 is not only coreless vs the TT81, it also has considerably higher torque, I believe. Those two characteristics definitely would add to the cost of producing the motors, for sure. It is more costly to make a high-torque coreless motor than a cored motor of similar torque characteristics. Also, coreless motors are more prone to overheating under stress, so that had to be considered in their design. And finally, what was the actual price difference between TT81 and TT101?

I know for Kenwood, their KD500 (I think that's the model), which was one very giant step down from the L07D in all other ways, nevertheless also came with a coreless motor. Pioneer used coreless motors in their Exclusive line of tt's; do the upper end of the Pioneer line tt's also have coreless motors? Don't know. Technics seems not to have used coreless motors at all, but as you pointed out, their best motors have 24 poles and the DC power supply could further reduce cogging to a non-issue. Motors and their power supplies are an art form unto themselves.
"Living Dangerously - Vintage DD Turntables"

Sounds like a good premise for a new and suspenseful reality series on The Learning Channel featuring adventurous daredevil audiophiles that love to push the limits beyond the norm.
I have my TT101 back and running once again. The tech changed out 8 capacitors, and I saw that the old ones were quite leaky. I dodged a bullet on that one. Cost was $150 including labor, parts, and tax. I am going to have the TT81 done as well.

I will follow this entry immediately with the second part of this story.
Another thing: I decided to check out the motor bearing on my own. There is a large screw at the bottom of the motor (visible by dropping the sheet metal cover on the bottom. It is sealed with some kind of hardened clay like material. I carefully scraped and vacuumed away the sealant and then I opened the screw... lo and behold I saw a small steel bearing and it was sitting in about 1/2 ounce of oil!! Dirty oil at that. The screw itself is a cup and at the bottom of the cup is a plastic thrust plate.
I cleaned out the old oil with a soft cloth and let it drip out - but nothing really did, and re-filled it with Mobil 1 motor oil. I didn't re-seal it as I will get back in there in a year or so and do it again and the screw/cup holds all the oil it needs.

I wanted to be sure the spindle/motor spun smoothly once I had it all back together. But, I heard a rubbing sound when I turned the spindle (platter off). Oh crap. I had torn apart turntables before so I thought - here we go again.

There are six screws around the motor on top - three hold the motor in place and three hold the black steel top plate of the motor in place. I took all six out (they were surprisingly tight) and lifted the plate off - no more rubbing sound. I spun and listened as I reassembled it and if I over tightened any of the screws the rubbing returned. Once back together, rub free, I put the platter back on, hooked it all up and voila! It spins free and long without any sounds. I don't know if the tech tightened things up or what happened but I am thankful that it was such a simple fix.
It is playing Oscar Peterson in Russia right now and Peterson's flying fingers sound ever so beautiful.