Click title to read one, or click date to read all below it.
10-07-11: Halcro
TT-101
Here is an image of the innards of a TT-101
INNARDS
and here is one of the TT-81
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:http://www.topclassaudio.com/web/eng...ls.jsp?gid=907 ]
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 idler.......you 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 of......so 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? :-)
Halcro (System | Reviews | Threads | Answers | This Thread)
10-07-11
Couldn't't sleep last night hal? :) Tpreaves
10-07-11
Wow, looks like an electronic pizza with the works....:-) Rockitman
10-07-11
I just got into another japanese dd table you haven't mentio ... Macdadtexas
10-07-11
Damn what a story. for myself i definitely feel i'm living ... Jedinite24
10-07-11
Dear halcro i have bought a few items from top class in the ... In_shore
10-07-11
Dear henry, most of the contents of the long passage you quo ... Lewm
10-07-11
Yes you are!! Ebm
10-07-11
This is an interesting thread in that i had planned to send ... Mgreene
10-07-11
Dear halcro, there is nothing as cruel as the thruth.no wond ... Nandric
10-07-11
I have to agree with lewm on this one. i made my living for ... Atmasphere
10-07-11
Dear nandric, go ahead and buy that tt101, if you want it. ... Lewm
10-07-11
Dear lew, i am not a brave man and have no intention whateve ... Nandric
10-07-11
Dear nandric, i read a little about the new data that call i ... Lewm
10-07-11
Relatively speaking, dealing with any vintage gear is riskie ... Mapman
10-07-11
If lewm is right, then mr. cheuk should terribly regret &quo ... Banquo363
10-07-11
Banquo, lewm is 100 % correct, also topclass currently has m ... In_shore
10-07-11
I wouldn't "dabble" in vintage dd turntables if i ... Lewm
10-07-11
I have no doubt that lewm is right regarding the vintage tec ... Banquo363
10-07-11: Halcro
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?
Halcro (System | Reviews | Threads | Answers | This Thread)
10-07-11
hi halcro. the bottom cover on the jvc is rather flim ... Hiho
10-07-11
Yes you are ! Waynefia
10-07-11: Halcro
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?
Regards
Henry
Halcro (System | Reviews | Threads | Answers | This Thread)
10-08-11
this is what i was alluding to in the synth world- its a bi ... Atmasphere
10-08-11
Thanks lewm. my sp10s are rebuilt by bill and at the time h ... Sonofjim
10-09-11: Halcro
Thanks guys.........particularly Lew and Ralph.
I did sleep better last night :^)
Halcro (System | Reviews | Threads | Answers | This Thread)
10-09-11
One brought up to spec technics sp10mkii - $1000 4 - 5 inch ... Ct0517
10-09-11
Dear banquo, what i did point out is that the service manual ... Lewm
10-10-11
I too have a jvc tt101 and a jvc tt81. i really enjoy these ... Aigenga
10-10-11
Speaking of my tt101 and tt81: i use aurios and still point ... Aigenga
10-10-11: Halcro
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 :-)
Cheers
Henry
Halcro (System | Reviews | Threads | Answers | This Thread)
10-11-11
The tt-81 and tt-71 use the same core motor. the 81 uses mo ... Hiho
10-11-11
Hiho, fwiw, that's the first thing i noticed once i got my l ... Lewm
10-11-11
An update on the recapping of my tt-101. i just spoke with ... Aigenga
10-11-11
Aigenga, i can tell you this: the main thing that causes spe ... Atmasphere
10-11-11
"small ones" does not tell me much. some electrol ... Lewm
10-11-11
A belated response to henry's question about the complexity ... Lewm
10-12-11: Halcro
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?
Halcro (System | Reviews | Threads | Answers | This Thread)
10-12-11
its worth the risk imo. firstly, the depreciation on a vint ... Pap
10-12-11
Halcro, i am using a thin sorbothane sheet against the platt ... Aigenga
10-12-11
Dear henry, the question you raise has also interested me fr ... Lewm
10-12-11
Ps. yes, coreless = slotless. just found a site that confir ... Lewm
10-12-11
As far as the sound difference between the tt81 and the tt10 ... Aigenga
10-12-11
Aigenga, i think what you wrote could also be termed an incr ... Lewm
10-12-11: Halcro
Aigenga,
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
OUTER RING
Halcro (System | Reviews | Threads | Answers | This Thread)
10-13-11: Halcro
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?
Halcro (System | Reviews | Threads | Answers | This Thread)
10-13-11
Henry, on that last post, one would have to peer into the br ... Lewm
10-13-11
"living dangerously - vintage dd turntables" soun ... Mapman
10-13-11
I have my tt101 back and running once again. the tech chang ... Aigenga
10-13-11
Another thing: i decided to check out the motor bearing on m ... Aigenga
|
|
