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.
TT-101
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 malfunction.....parts are 'unobtanium'....and they often cannot be repaired.
128x128halcro
That TT-801 on Yahoo Japan looks in fine nick Banquo....although it doesn't have the original pressure-seal mat.
That Victor TS-1 air supply also on Yahoo Japan would be a risk Dover as the Seller hasn't tested its operation and is advertising it 'as junk'...😢

Interesting points about the differences between the 101 and 801 Banquo...and as Lew says.....the differing platter weights and chassis weights are intriguing.
Is this even BETTER than the TT-101?

Maybe this is the one for you Halcro?
Haha....I guess it IS close....👀
From the looks of it though, it appears that someone has messed around with it quite a bit....
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.
On the topic of chips a fellow is doing some interesting work
on the SP10MKIII's and reworking some no longer available and susceptible to failure parts.

Great to have someone spend that much time and effort for
the relatively small numbers of tables it is applicable to.

http://www.audiokarma.org/forums/index.php?threads/new-technics-sp-10-mk3.659118/page-10


The story of Thuchan's 'chip' is quite complex.....
After about 6 weeks of his Bavarian Tech taking apart the Victor, Thuchan Emailed me that it needed a 'chip' which his Tech had ordered from China but which didn't arrive.
He gave me the chip No. which I promptly Googled
http://www.ic2ic.com/search.jsp?sSearchWord=SC3042&prefix=S
to discover that this seemed to be available everywhere.....even in Germany. So I sent this information....
6 weeks later Thuchan says his Tech can't get the 'chip' and again I do another Google search with different results for this 'chip' available all over the world.
6 weeks later....can't get 'chip'.....can I help..🙏🏽
At this stage I had no idea what No. 'chip' Lew had stashed 2 years ago....but as I could do no more, I told Thuchan to contact Lew on the off-chance...👀❓
And as fate would have it......Lew's 'chip' was the 'magic' one...
A story with a happy ending...🎼🎉
Wow rwwear......sounds like an amazing Victor..😍
Can't wait to hear what you think when you have it?

Regards

Halcro.
Does the chip have a manufacturers name on it? I also noticed there were some chips with "B" as a suffix. Are they different?
Lew would know know more about the chip than I do.
I haven't even seen the damn thing...🙈

I think the chip was made by NPC, which stands for "Nippon something something".  I will check the label when I am able to get to it.  It is indeed a good idea to specify the maker when ordering, so as to be sure there is no confusion, even though there should be one and only one chip configured like the SC3042. (This is from memory, but I think correct. However, I could be thinking of the designation for the Denon DP80 chip, a more rare bird.) Whether that designation can optionally have an "A" after it, I do not recall.  My experience has been that several of the vendors that offered to sell me this chip have never ceased to email me to ask whether I want more of them or to try to sell me something else in the realm of solid state parts.  I probably get at least an email per week.  At the time, I just picked the seller who seemed to have the best grasp of the English language.

Henry, it's a 16-pin rectangle with 8 pins per long side.  You'd need a special soldering iron to de-install the old one and install a new one, or great skill with a conventional soldering iron.

Totem, Thank you for alerting us to the thread related to SP10 Mk3 speed regulation.  I've digested it thoroughly.  What I don't get is whether the guy who figured this out and went to the trouble of creating a PCB, on which to mount his circuit that replaces the single chip that "runs" a Mk3, is selling or is going to sell the PCBs along with instructions on how to stuff the board.  I would be interested for sure, as the owner of an SP10 Mk3 that I bought NOS and which works perfectly as is.  One cannot be too vigilant about potential maintenance needs. Plus he seems to infer that his circuit is actually more accurate than the original chip, although I don't know whether one needs to worry about a few Hz when the frequencies in question are in the millions of Hz.

By the way, a dirty little secret of SP10 Mk3 world is that the very same chip was used inside an SL1500 or SL1600 turntable, either of which is usually available for a few hundred bucks.  I know some guys who have stockpiled a few of those so to be able to repair their Mk3's.

lewm
   .
What I don't get is whether the guy who figured this out and went to the trouble of creating a PCB, on which to mount his circuit that replaces the single chip that "runs" a Mk3, is selling or is going to sell the PCBs along with instructions on how to stuff the board.
    

The maker JP does intend to sell the board for use in the SP10MKIII's
and I have inquired as to contacting and selling, and will post his reply.
       


rw, Thank you for doing the legwork to unearth the fact that it is the SL1300, and perhaps not the SL1500 or SL1600, that utilizes the MN6042 chip also necessary in an SP10 Mk3.  Sorry for my alphanumeric error.  I was going on second-hand info received from a fellow Mk3 enthusiast.

Totem, Please do keep us posted.  I am a buyer.

I am also thinking hard about sending my Victor TT101 to Germany so that Thuchan's guy can fix it, once and for all.  I got an email from Thuchan today; he is thrilled with the sound of his TT101.  This is a guy who owns some of the most expensive turntables in the world, so I take his praise for the TT101 very seriously.


The MN6042 is used in the MK2 versions of the SL-1300/1400/1500/150, the SP-15, SP-10 MK3, and SP-02.  

Lewm: not millions by any stretch.  The nominal frequency through the pitch chip is 262.080KHz.  This is also where I'm seeing ~8Hz variation across the three samples I measured.  

The output of the pitch chip is delivered to the DN860, which divides by 1/8, then 1/54 for 33RPM, and then 1/12 to the AN660 chip.  The "quartz locked" frequency for 33RPM is 50.5555Hz, which is the frequency the AN660 uses to develop the reference and error control lines to the motor drive. 

For perspective, the AN660 sees 50.5555Hz for 33RPM at 0.0% pitch, and 50.6061Hz for 33RPM +0.1% pitch from 262.080KHz.  262.074KHz is 50.5543Hz to the AN660, and 262.081KHz is 50.5557Hz at 0.0%.

Theoretically instability in the reference frequency should manifest as a voltage instability in the reference line to the motor drive.  We'd then need to determine how the motor control would react to the degree of variation induced.  My theory is this would work in concert with the offset voltage adjustment; tighter control of the reference voltage would allow the drive to be more critically damped. 

When I get the next revision of boards in I'll put the motor on the bench and measure through the entire system.  I haven't managed to find a test record anywhere close to the quality needed to reliably measure flutter below 0.02% JIS, so my conclusion on whether the increased stability of my chip replacement equates to anything of note at the platter may be based upon a bit of conjecture. 

Worst case, it's designed to be a modern, resilient drop-in replacement for any circuit that uses an MN6042.  Best case, we've made things a bit better in a meaningful way.

I do plan on making it available, as I'd love to have a shot at recouping some of the R&D costs.  It's amazing how fast things add up.  As the largest component on the board is a 4x4mm 20 pin package with no leads, I wouldn't offer it as a kit.   Please PM for info. 

JP


 
As a MK3 owner myself it was interesting for me too. There's still many IC's inside the MK3 though. Aren't they just as important?

I just bought a JVC QL-F6 that is supposed to be in good working order. Hope so.
http://www.thevintageknob.org/jvc-QL-F6.html
As Lew said... Thuchan has just completed his preliminary set-up and listening sessions with his re-built TT-101
https://audio16.wordpress.com/2016/01/21/victor-international/
Audio16 is his own Weblog where you can see his current amazing system components.
His initial set-up is similar to my initial beginnings
http://i.imgur.com/Xp97BF8.jpg
but he is having a slate cradle made to match my granite one
http://i.imgur.com/S97uGns.jpg
I look forward to him also writing a few words here about his vintage DD experiences....because he has had quite a few 👏

PS Lew, note the Copernican isolated armpod setup that doesn't seem to trouble Thuchan 👀❓
lewm
Totem, Please do keep us posted.



JP has given me permission to post a contact regarding the SP10MKIII
chip design.
 jp@fidelisanalog.com
Lewm 01-22-2016
"What I don’t get is whether the guy who figured this out"
"he seems to infer that his circuit is actually more accurate than the original chip, although I don’t know whether one needs to worry about a few Hz when the frequencies in question are in the millions of Hz"
Lewm
If you had "digested the thread thoroughly" as you claimed, you would have understood that jpjones has comprehensively researched and measured both the original circuit and components and has carefully measured and tested his new board at every stage of development. You are wrong to claim that he "seems to infer that his circuit is actually more accurate". Jpjones provides test results and scope data that support the published results. This provision of test data is a breath of fresh air compared to the faith based changes touted by others in this thread who provide no test data and furthermore argue that test data is not needed to support their claims.

richardkrebs  12-08-2015 4:00pm
Dover.
You are quite correct. I do not provide any objective proof that the number of servo error corrections have been reduced by my upgrade. However since I know what the upgrade process entails, it is reasonable to conclude that this is indeed true.
It is surprising that you, as a doctor, prefer to support unsubstantiated claims whilst trivialising others who have provided extensive test data that support their observations and claims.


Post removed 
I don't know what the genesis of this friction is, but I'd be very appreciative to not be used as cannon fodder in it.  I'm just a guy trying to save good tables, and perhaps make them a bit better in the process. No more, no less. 
Post removed 
Dear JP, Congratulations on your perseverance and genius in pursuing the Mk3 "problem" to its potential solution.  Now that you're here, and pursuant to Dover's lament and criticisms, did you mean to infer that the apparently increased accuracy of your circuit vs that of the MN6042 would confer a meaningful, not to say audible, improvement in the performance of the Mk3?  That would be really something to behold.  Like I may have said above, in reading your posts on Audiokarma, I was not sure that the few Hz by which your circuit "beats" the MN6042 in accuracy would necessarily translate to performance.  But this is also because I may have a misconception about the true meaning of those data points you posted.  Can you comment further?

Also, I will be contacting you privately about purchasing one of your boards.  Thanks again for your work.
Dear Dover,  To ask a question or to wonder is not to "trivialize".  The basis for learning is questions and answers. That's about all I can say to you that is not vitriolic.  I would hope that JP appreciates the fact that my earlier post meant him no disrespect at all.  In fact, I am rather amazed at his work, since failure of the MN6042 has been the downfall of many Mk3s.

Dear JP, I now see that you did in fact respond to my question about the accuracy of your circuit vs that of the MN6042.  Sometimes these threads move too rapidly for me to be current. I did wonder whether 262.XXX kHz was the operative number or whether it was the much higher frequency that gets divided to yield 262.XXX kHz.  Now I know it is the latter, which enhances the significance of the difference between your circuit and that of the MN6042.  What's additionally appealing about your circuit is the fact that if it ever should fail, it's fixable with parts that are readily available.
I still have question about the other chips inside the MK3. Are they easily found, not as important or just don't ever die?
rower 01-22-2016 1:19pm
I still have question about the other chips inside the MK3. Are they easily found, not as important or just don't ever die?

Someone like Bill T would have better first-hand knowledge, but in my research nearly all the examples I could find that had DN860 or AN660 failures had tell-tale signs of prior work that didn't appear very impressive.  I just didn't see any evidence of "spontaneous" failures for any of the other ICs like you do for the MN6042. 

The motor drive IC, AN640G, is still plentiful, but those don't seem to ever fail.  AN660s and DN860s still show on eBay once in a great while as have a couple MN6042 recently, but they're becoming few and far between unless you strip a lower model 'table. 

Not as easy as the MN6042, but I think something could be fairly easily made to replace the DN860.  That's not to say I think it'd be worthwhile though.  I've a bit over two months and well north of $1000 in to the MN6042 replacement. 

JP
If you ever get tired of your SP10MKIII endeavors, there are
a few anxious owners of Victor TT101,s hanging about.

The thread posted by Halcro previously "audio16" shows what
its all about.
Lewm has one that is currently not operable.
Interesting.  The SC3042 IC is similar to the MN6042.  Not sure it's worth while, but happy to have the conversation. 
Totem and JP, As you also may be able to glean from reading Halcro's and my recent posts, a few years ago I was able to find and buy about 10 samples of the SC3042.  In the last few weeks, I sent two of them to a fellow aficionado in Germany, known to us as "Thuchan".  Thuchan had evidently purchased a broken TT101 with Halcro's help, and his tech determined that it needed replacement of SC3042.  Until this recent episode, I had no idea whether the chips I bought (from a vendor in Hong Kong) were genuine or even in operating condition, but Thuchan's tech got his TT101 up and running perfectly by virture of installing the chip I sent.  This is great news for me as well, because I have more SC3042 chips on hand. (By the way, I think they are still available from China and Hong Kong.)

My own TT101 has been "broken" too, since purchase about 3-4 years ago.  For that reason, I got it at a low price, approximately the value of the tonearm that came with it.  I happen to live very close to Bill Thalmann's shop in terms of highway driving, and Bill early on replaced all the electrolytics in my unit.  However, in Bill's shop, once the lytics were replaced, the TT101 refused to misbehave.  It worked perfectly on each of two visits to the shop.  In my house, it worked only intermittently, and every time I began to feel confident about it, it would go "on the fritz".  I tried all sorts of black magic to no permanent avail.  Then I started to try to trouble-shoot it myself. Suffice to say that in the process of trying to fix it, I converted the intermittent problem to a permanent and consistent problem.  Also, I am pretty sure at least that the problem is local to the PCB that contains the SC3042, although I lack the expertise to prove it's the SC3042.  (There's more than one chip on that board, and the others are not SC3042s.) However, Thuchan's tech tells us that his unit was misbehaving in a way similar to mine, so now I have hope that replacing the SC3042 may finally fix it.  How's that for a saga?

Bill worked on my SP10 Mk3 and on my Denon DP80. He's a great guy, and we are lucky to have him. Now that my TT101 is reliably malfunctioning, I hope to take it back to him for the 3rd time to finally trouble-shoot it. Either that or I may send it to Thuchan's tech in Germany, if the postage is not prohibitive in cost.

JP, Are you in the DMV area?  I'm watching snow accumulate on my car outside.

I do think there would be interest in an SC3042 PCB re-creation, certainly on my part and especially if the discrete circuit can outperform the chip.
Nothing worse than an intermittent problem, so it was good you made it permanent. 

I'm in NYC.  Nothing here yet. 
Got my Victor TT101 today, which have some speed issues - knew this when I bought it, so no surprise there.  My initial impression is that its overly complex, especially compared the the Technics SP10MK2 and MK3, which I both own too, and have refurbished.  Also especially complex if compared to the Denon DD tables I'm usually working on (DP3000, 2000, 6000 and 80)  

The motor seems robust - however the SP10Mk3 and the Denon DP80 in my opinion have more solidly built motors.  

It'll be interesting to get this one up and running correctly,  Ill give an update once it get it fully operational.

Good Listening

Peter
PBN, FYI, you're looking at a coreless motor.  They are built quite differently from the iron core motors used in both Denon and Technics DD turntables, in that you see no iron poles wrapped in coils of wire and in that iron core DD motors tend to be oriented vertically, shaped like a cylinder, whereas the TT101 motor and other coreless turntable motors are oriented in the horizontal plane.  Further,  "pound for pound", iron core motors will tend to have more torque than will coreless motors.  Plus, the latter have more issues related to cooling.  All that said, and given that you may know all of the above, IMO, coreless motors impart a certain effortless and very musical quality that is rather addictive. Of course, my opinion is based on the Kenwood L07D sound, since I have yet to hear my TT101.  Whatever one may say about the Krebs mod, data or no data to support it, to my ear the Krebs mod makes the SP10 Mk3 sound more like the world's best coreless-motor-driven tt than like the world's most powerful iron-core-motor dd tt (which it also is).  (I've got a DP80, too.  I kept it over the SP10 Mk2, because I thought it sounded better.)

Thanks for the update Peter.
I didn't know that you were actually getting a TT-101...
Will be following your comments as you delve into the morass...🤕

I'm happy to say my recently purchased JVC QL-F6 works and sounds great. It's not the most beautiful turntable I've seen but could look nice in a custom cabinet.
http://www.thevintageknob.org/jvc-QL-F6.html
A Victor TT-81 available for a song
http://www.hifido.co.jp/KW/G0301/P0/A10/E/0-50/S0/C15-01917-33022-00/
HiFiDo is an excellent Japanese Seller who tests each and every component before offering it for sale.
You can trust that this deck will work perfectly...and it has a one year warranty.

rwwear: "I'm happy to say my recently purchased JVC QL-F6 works and sounds great. It's not the most beautiful turntable I've seen but could look nice in a custom cabinet."

I am glad that you like the result. It's a gem. As long as you like the tonearm, it's as good as any other tonearm-included JVC turntable or integrated turntable out there that uses coreless motor. I have the same one and the QL-A75 is the only other one I might want to acquire in the future. Yes, she's not the prettiest but she can cook! 

halcro: "If hiho likes it.....it's safe to assume it's very good"

You're way too kind. I've learned more from you, your audio dedication, and your open-mindedness than most people here. My humble opinion is just . . . an opinion. As the saying goes, "trust your own ears." 


rwwear:  "The A75 is beautiful."

Indeed! I meant to say the QL-F6 is "not the prettiest but she can cook" up some good sound! 

Thanks Hiho,

I meant to ask...and you may have already written it somewhere....what cartridge are you currently listening to?

Regards

Hiho or anyone else that knows, are there any issues with the F6 I should be acquainted with?

Living dangerously is expecting A'gon dispute system to help you get your grand back after some hustler has advertised one thing and sent you another . Process only gives the hustler the chance to say too bad sucker,
Too many sharks on here, I've bought my last thing on here.
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