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

Richardkrebs,

Why don't you just make stuff up like most manufacturers?  People don't know what it means anyway. Imagine a turntable going from 70dB S/N to 90dB !!  You could pretend to rewrite the laws of physics with some doubletalk about external acoustic compensation curves or some such nonsense.

Wow and flutter - not a problem. Just buy a few crappy off-center test records (aren't they all?) and you could have before and after "proof" of upgrade effectiveness.  Enlarge the hole in one of the records and carefully center it for your after sample. 

Regards,

Dover,

You're way out of line posting your belt drive BS on this thread.  It doesn't matter how good it supposedly is, it's inappropriate.

Like your bit about absolute speed and the rotation of the earth, it doesn't make sense. 

Fleib 12/13/2015

Dover,

You're way out of line posting your belt drive BS on this thread. It doesn't matter how good it supposedly is, it's inappropriate.

 Fleib, you are addressing this concern to the wrong person.

A review of the posts since 2011 shows that is others who are  starting discussions and making comparisons on belt drives in this thread. For example -

 Doron & Harold-not-the-barrel started a discussion on the Oracle BD in September 2014.

Halcro, the originator of the thread, started discussing the merits of various BD’s vs DD’s and their relative Feickert speed test results and graphs in October this year.

You and Richardkrebs were discussing belt drives with respect to Bruce Thigpens test results on wow & flutter in October this year.

I have only responded to others comments on BD’s since Halcros Feikert discussion in October.

 

The FIRST person to bring up the performance of the Final Audio VTT1 thread drive to this thread was in fact Richardkrebs in this post

Richardkrebs – 5/11/15

There, one TT is mentioned where specific data is given on the amount of laser pointer movement per revolution and its distance from the centre spindle.

This TT is a beautifully engineered machine with, from memory a 22 kg platter driven by a fractional horse power motor via a thread. Hereafter I will call this TT. "TD"

The specifics were 2 mm movement on a radius of 400 mm, per revolution.

My first post and only post in this thread on the Final Audio VTT1 thread drive in the 4 years up until October this year was a response to the misleading comments posted by Richardkrebs -

Dover 5/14/2015

To be clear what was being measured in my post on the Timeline thread – the 2mm lag was generated by setting the TT speed with no stylus playing and then measuring the lag when playing. A 2mm lag at a radius of 400mm is a speed error of 0.08%

If I set the speed with a record playing, which is my normal procedure, then there is no speed error at all as measured on the Timeline, and therefore the variation in stylus drag due to music playing is an immeasurable % age of the total drag.

If we assumed that the variation in stylus drag is plus or minus 20% of the total drag (remember it is not registering at all on the timeline), then the string drive Final Audio VTT1 has at worst about half the wow and flutter of an SP10mk2, and about the same as an SP10mk3, without the induced negative effects of the servos.

The SECOND person to bring up the Final Audio VTT1 thread drive in this thread was Halcro in this post - 

Halcro - 10/24/2015

It is indeed revealing that Dover has never had the intestinal fortitude to post his Final Parthenon turntable performances under both the Timeline and the Feikert Speed App yet continues to boast of its abilities. I am dubious in the extreme.....😎

Halcros comment flabbergasted me as the only mention I had made in this thread re the Final Audio VTT1 thread drive prior to his post was the single response to Richardkrebs post.

Clearly some folk feel the need to question the performance of the  Final Audio VTT1 even though I never raised it in the first instance, or even the second. You will have to ask them why they keep bringing it up in this thread, but if it is maligned, then I may feel obliged to respond.

As to the subject of the thread “ DD are we living dangerously” then all turntables are relevant. In order to assess this proposition one needs a reference.

For example, one could argue that the Linn LP12 BD presents a very good case for being the gold standard for "living less dangerously" as it is one of only a very few turntables where one can have the manufacturer repair and refurbish any turntable they have ever made.

In terms of the Final Audio thread drive – mine is around 40 years old, used every day and has never broken down, ever. The oscillator preamplifier ( speed controller ) is completely original, never been recapped or repaired in any way shape or form. The only servicing required in 40 odd years of operation has been a re-lube of the motor and a change of oil in the main bearing every few years.

Cheers

 


Post removed 

Dover,

Seems I made a mistake. I gave you an opening to spout further, but I think you would have found the opportunity anyway. The problem is, I don't believe you, about the SQ of your table and how it relates to speed stability.  It's not that I think you're being deceptive, it's your judgment I question.

"As to the subject of the thread “ DD are we living dangerously” then all turntables are relevant. In order to assess this proposition one needs a reference."

This makes as much sense as your absolute speed declaration. Looks like you teamed up with Raul who graced this forum after a long absence, to support you, and you returned the favor on the MM/MI thread?  Doesn't matter.

You ask for proof from Richardkrebs, yet offer subjectivity to support your claims. Where's your timeline, where's your sound bite?

Cheerio,

Dear RichardKrebs:  "" We do not listen to specifications.
If we did, tube equipment for example, with its typically inferior measured performance, would be off our Christmas shopping list.
My view is that we can hear way deeper into the output of a product than measurements can articulate. ""

Agree, we listen to sound waves in the air. I think that the whole true hig-end audio community is " suffering " a historical trend/cancer  where almost no one really cares on what we are really listen to. That trend said: " the best judge are your ears ".  Audio retailers, reviewers and almost all the audiophiles ( like you . ) believe that's the " Byble " and that's all about and is not a fault of any one of us. As I said is just that trend/cancer that corrupted our today hobby.

Tubes is a very good example of that corruption but this is not the thread to talk about.

I don't " blame " you in anyway because you did not measure before and after, almost no one does, but could be really interesting for you ( the " creator " of that mods. ) where you are " seated ". If you want to disclosure to the audio community or not: this is your privilege. I can tell you that if I decide your mods to my units I really like to have those " numbers ": before/after.

I remember, many years ago, when was developed our phonolinepreamp ( Essential 3150/60. ) that its " sounds " was just " fabolous/spectacular " against what I heard on top similar audio units and for us was not enough our subjective judgements and we measured that unit and found out that its numbers were " unvelievables " ( example: even today the best units can't approach or beats our fully analog RIAA deviation: 0.012dbs! ). These gave us certainity on the why's and what we were " proclaming " in the whole quality performance of that audio unit.

IMHO, subjectivity or objectivity alone means almost nothing. My opinion is that both " words " are faraway from be one against the other but that exist an intimate realtionship in between and IMHO we need to know it instead that: " I like it ".

Richar obviously don't take the " road "  posted here:

"   People don't know what it means anyway. Imagine a turntable going from 70dB S/N to 90dB !! You could pretend to rewrite the laws of physics with some doubletalk  ..... "

that IMHO is almost an " insult " to the audio community but each one can gives its opinion in this " free world ".

Thank's for your answer.

Regards and enjoy the music,
R.

 


Post removed 

Raul,

**Richar obviously don't take the " road "  posted here:

"  People don't know what it means anyway. Imagine a turntable going from 70dB S/N to 90dB !! You could pretend to rewrite the laws of physics with some doubletalk  ..... "

that IMHO is almost an " insult " to the audio community but each one can gives its opinion in this " free world ".**

It seems my joke/sarcasm went over your head, but that's understandable given a previous post:

**Lewm, just think this:

suppose that your unit, before the mods, was running on manufacturer specs. Example 92db on SN ratio: what if after the mods that " figure " gone down to 84db?**

You were talking to Lew about Richard's mods. Before this post I would have guessed that everyone on this thread knows those S/N figures on a turntable are impossible. 

S/N ratio on a component like a preamp is referenced to an output voltage level. S/N on a turntable is a rumble figure and is limited by the dynamic range of a record. Maybe you'll tell us you meant something else, but that was the topic.

I deleted an earlier post which I thought might be too harsh.

Happy holidays,


I own two technics sl1200mk2 silver, and one sl1200mk2 black. Still use them, 25 years still perfect.  Silver ones stored for 15+years, unboxed, opened up, cleaned spindle, added fresh oil, plugged in, and pressed start, and still perfect.....they don't make me like this anymore, that's for sure. 

Halcro,

One thing I've been meaning to ask you, do you know why your 101 sounds better without the metal cage around the motor unit?

I don't have a plinth or stand alone design for my 81 yet so I can't try it, but I also can't come up with a reason why this should be so. 

Regards,

Fleib,
Congrats on your TT-81. Any ideas on how you're going to mount it?

Can only speculate on the reasons, supported only by my empirical observations.
I now know that the motor unit and electronics of the Victors put out RFI/EMI as the metal cage definitely acts as a Faraday Cage in neutralising and dissipating these when in a restricted enclosure.
I can only surmise that when mounted fully 'nude'.
http://i.imgur.com/jJoTuv4.jpg
The electrical waves dissipate quickly into free air.
The differences at any rate were quite subtle and are easily supplanted by the improvements made with the 'mass loading' onto the granite plinth.
At any rate the question for me is now 'mute' due to the necessity for the grounded Faraday Cage in my new arrangement.
http://i.imgur.com/msMbfXy.jpg

http://i.imgur.com/UAEMFj7.jpg
We may not have to rely on vintage DD turntables anymore.
There appears to be a distinct revival....
http://www.monoandstereo.com/2016/01/technics-grand-class-sl-1200-turntables.html#more

http://www.monoandstereo.com/2016/01/grand-prix-audio-10th-anniversary.html#more

Could it possibly be that the Linn counter-revolution against the Japanese DD decks in the 70s was motivated by production costs alone.....❓👅


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.

Halcro, I wasn't sure exactly what I am doing with the TT81. I can get an old Victor plinth relatively cheap, but I've decided to copy your design, with changes of course. 

Other things have come up and it hasn't been to the tech yet, but it runs and I have a 100V converter.  I'm thinking of making a pod out of Kenwood style composite - ground limestone with polyester resin. 

There's a ground screw on the bottom of the metal cage. I read somewhere that's it's necessary to use it. Any comment?

Sorry my response took so long.

Regards,

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.

Lew, I think that would be near impossible and might be better without the coupling. Isolating the motor unit from the arm would eliminate vibrations shared one to the other. On the other hand, outside energy hitting the platter or plinth would be different from that hitting the arm (board).  There would be similarities, but I'm not sure if shared vibrations is a positive thing. Would micro detail increase or decrease?

In this case I see the value in the Halcro approach. I think it might be better, if executed well. Looking at the stock Victor plinth it seems like just a plywood laminate with a hole in the middle with 2 wood armboards. I think I can make a better plinth, but not sure I want to.

Regards,

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?

The interesting thing about this new technics turntable is that Jonathan Carr appears to be involved or in some way supporting it.....
http://www.analogplanet.com/content/new-technics-sl-1200gae-not-your-fathers-old-technics-sl-1200mk2...
I can't recall him ever expressing a liking for DD technology on these Forums?
Fleib,
I'd recommend that you at least try the 'Halcro' method...😎
But please don't underestimate the importance of a REALLY heavy armpod...that's the real message of the Copernican Thread.
Most armpods I see folks using are made of aluminium or hollow type construction which IMHO will not create the conditions I talk about.

Lew prefers to talk 'theory' without having the practical experience.
I have actually heard in my listening room all the comparable 'theories' of platter/motor/arm variations and Lew has not.
That never stops him...
I long ago learnt in this hobby......experience trumps theory almost every time 👍


Lew, It seems to me that w/o a suspension, the advantage of a chassis or plinth coupling the parts, is lost.  Instead of the chassis being a rowboat it's the base supporting the structures. If vibrations are affecting the motor unit they are more likely to affect the arm, if coupled.  The back and forth of vibration transmission would smear the sound.

In reality, I think either approach can sound good with good parts and execution.

Regards,

Halcro, Thanks for the tip, I figured as much. Does your new design change the attachment of the motor unit to the base?  I was thinking of bolting it on and using compressed sorbothane washers.

It will be awhile before I can get it together. Right now I'm devising a scheme for the actual build.

Regards,

Fleib,
I still just rest the TT-101 on three butyl rubber pads stuck to the granite cradle...
http://i.imgur.com/h673918.jpg
They are the same as the ones I had on the stainless steel cradle...
http://i.imgur.com/UuEyECm.jpg
http://i.imgur.com/qEWvSHn.jpg
I figure that the 10Kg weight of the motor unit resting on the hard rubber pads creates enough friction not to move and also allows me to remove the TT-101 from the cradle very easily.

Your thought of bolting and sorbothane washers is probably better although the more compressed the sorbothane becomes.....the more 'coupled' to the substrate the turntable becomes, which could possibly colour the sound?
Good luck and please keep us informed of your progress...

Interesting.  There are quite a few things to figure out and it would be easier to incorporate them in the initial build, then to add-on later.  If I want to bolt the motor unit to the structure I should embed threaded inserts and have space beneath to accommodate the bolts.

This Kenwood ARCB stuff will probably be like working with clay or epoxy putty. I should be able to add on layers.  I know you can drill/cut it, although a little messy. Polyester resin is auto body patch material (Bondo), and I'll have to experiment with mixing and sculpting. Seems a whole lot easier to drop it in a plinth. 

I could build a better (than stock) plinth and I wonder if the pod approach is worth the extra trouble.  I'd have to make arm pods as well. 

Still mulling this over, but pods are intriguing.  I also have an old Sota Sapphire I don't use cause it can't keep proper speed.  If I podify that w/new motor, I could have 2 set-ups and 4 or 6 arms and sell a few tables. Sounds like a plan.

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?
Ahh Lewm......the Master of illogical analogies.
Firstly we have the "rowboat in the floating sea" analogy whereby the stable platform of your shelf or rack is likened to the unruly fluid of the sea and the vibrations which uniformly affect the rigid shelf are compared to the multifarious currents and winds acting on a thermal fluid in constant motion.
In this ludicrous juxtaposition.....he then places two separate boats instead of one contiguous raft...
But now Lewm surpasses himself....the results of a person jumping off a roof are well known to be less than happy whereas the results of a person using outboard armpods are so far universally 'happy'. So how goes the analogy....❓

But I also can be somewhat amused with "thought experiments"
The Kenwood L-07D
http://i.imgur.com/VvgdWQi.jpg
which directly connects its platter bearing to its tonearm support via a cast aluminium structure, condemns the fixed mounting dimension of the tonearm to expand and contract with changes in temperature. Over a 10 centigrade degree range, this dimension could possibly change by a few millimetres rendering your carefully executed arm geometry useless.
Furthermore....connecting the arm support directly to the supporting spindle of the platter, inevitably transfers all the vibrations of the revolving platter into the arm base, a design failure of mammoth proportion.
The belief that all turntable designers (and designs) of the past were competent is a demonstrable unfortunate absurdity.
Halcro
Over a 10 centigrade degree range, this dimension could possibly change by a few millimetres rendering your carefully executed arm geometry useless.
This seems a bit far fetched - a piece of aluminium 255mm will only expand by 0.0587mm for a 10 centigrade temperature change according to my calculations. Steel and bronze would be much less than this. Perhaps Halcro, since you design bridges, you could explain your maths.


Halcro
We have been thru the thermal expansion thing already. As I stated some months back, with an aluminium chassis, the change in spindle to arm distance due to delta temp is very small. Dover is correct, it is no where near a "few millimeters"
Of course the shelf on which you place your TT isn't immune to dimensional changes due to temperature. Don't know the material you use, but the change is also likely to be insignificant.

Cheers.



a piece of aluminium 255mm will only expand by 0.0587mm for a 10 centigrade temperature change according to my calculations.
You're correct Dover. Quite small but as record grooves are in the order of microns...I wouldn't be boasting about this concept as you and Lewm do.
The tonearm vibration is a more serious issue however.

BTW...it's not often an architect gets to design a bridge.
Halcro - indeed it is quite something to have designed a bridge. When you mentioned designing a bridge in your earlier posts I thought you were a dental technician, until I found out that you were an architect. I studied engineering at university and most architects only do a couple of basic engineering papers for their degree in New Zealand.
As regards vibration - yes I agree it is an issue. The Final uses a superplastic zinc alloy chassis base that dissipates any vibration between 10 & 100hz at room temperature internally at a molecular level. Both the platter and arm pod are bolted to this SPZ energy sink to achieve both loop rigidity and deal with vibration. 

Dover,
When I graduated in 1970, a University Architecture degree in Sydney was 5 or 6 years of full-time study with Structural Engineering being a compulsory subject for each and every year.
But it was really 40 years of professional practice consulting and co-ordinating with all the relevant engineers (Geo-Tech, Structural, Civil, Hydraulics, Mechanical, Electrical, Acoustical) that taught me more than a mere 6 years of university study ever could...😎
I'd appreciate it if you could send me the Post where I said I had designed a bridge....as I haven't and I don't believe I wrote it? As I said.....very few bridges are designed with the input of an Architect.

When you say you studied engineering at university....did you graduate? 

Halcro - Yes in finance - switched to finance after a couple of years, decided engineering was not for me. I should have done an architectural degree in hindsight as that interests me more than civil engineering. Cheers.

I am a direct drive enthusiast and have become interested in JVC after reading this article:http://www.soundhifi.com/images/DC%20Technics%20SL-1200.pdf

Do any of you have any experience with the Victor TT-801? It appears to be even better in some regards to the 101. http://www.thevintageknob.org/jvc-TT-801.html

I am the proud owner of a Technics SP-10 MKIII, an SLP 1200 MKII, a Teac TN-400 and a Micro Seiki FVG RX-1500. I also have an Empire 698 which isn't working at the moment.

Thanks for those articles rwwear....especially the one by Dave Crawley on Quartz lock where he debunks the myth of 'speed hunting' that has regularly been levelled at DD decks by its antagonists.
The TT-801 seems to be a stripped down TT-101 (without the 1 Hz step pitch control circuitry) with an added vacuum hold-down.
I have no problem with vacuum hold-down per se.....but here's where 'vintage' and 'dangerously' very much apply, as a special rubber perimeter seal is required for the platter and if this is damaged or perished....where does one obtain a new one?
Banquo has recently scored a TT-801 to partner his trusty TT-101 and hopefully he can contribute here ❓👀

I agree with the worry about the rubber which my Micro has. Although I never use the Micro, I intend to someday.

The 801 appears to have even more IC's then the 101.

If anyone is interested:http://www.ebay.com/itm/140827896694?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Halcro:

Not quite bridge design, but google the "Bayonne Bridge roadway raising". Still the world's 4th longest single arch at nearly 100 years old, only the original arch will remain when work is completed in 2017. I visited family in Bayonne last month and was amazed to see the project even  at partial completion. 

I hope my being an SP10/Krebs upgrade owner allows me to go briefly off topic...
So that's the Bayonne Bridge...?
When I first visited NY in 1984, I was shocked to see what I thought was a copy of our famous Sydney Harbour Bridge which opened in 1932
http://2.bp.blogspot.com/-xM4JuGOb_fc/T2VA_JxTW7I/AAAAAAAADm8/4gtCt_JPpWc/s1600/SydneyHarbourToday.j...
I must say....it doesn't look as attractive with the raised roadway..🤐
And speaking about expansion of metals.....at the two bases of the arch of the SHB, there are giant steel rollers so that the arch can 'spread' due to load and expansion. Those stone pylons are purely decorative...
Halcro, I agree with you completely that the Bayonne Bridge will be less attractive with the raised deck. I spent my youth living in the shadow of the original design.  We used to jog the walkway, summer and winter, with a spectacular view of the southern tip of Manhattan. 
Anyone please explain me what is the difference between Victor TT81 and TT-801 ?  
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.

It appears the 801 is actually slightly more complex than the 101. I believe I would just as much prefer the 101 because it is more easily serviceable I suppose. As far as the rubber goes, my Micro Seiki has a rubber platter ring and it is as good as new but if it became damaged it would be expensive to replace. You could easily get by without using it of course and simply put a mat over it.
http://www.vinylengine.com/turntable_forum/gallery/image_page.php?album_id=106&image_id=16222

http://www.thevintageknob.org/jvc-TT-801.html

I haven't had a chance really to play around with my tt 801, but here are some observations.

1. The tt 801 DOES have the stepped pitch control like the tt 101. The control panel and speed indication is different though. Instead of showing the actual change in speed like the 101, the tt 801 displays '33/45 +/- .n' where 'n' refers to the number of steps up or down away from 33/45. Additionally, the 801 incorporates a reset buttton to quickly return to 'normal'.

2. The platters are different. The tt 101 platter weighs 1636g and the tt 801 weighs 2706g. The tt 101's platter is damped by a rubber ring seated (glued) underneath, while the 801's platter incorprates 2 rings that are secured to the aluminum via 6 screws.

3. Perhaps as a consequence of the heavier platter, the 801's motor has greater torque.

4. Although the 801's platter is heavier, the 101 motor unit is acually heavier. The materials making up the bezel of the two units appear completely different. The 101 is solid underneath the bezel, while the 801 is surprisingly delicate there.

5. My 801 didn't come with a rubber mat so I don't know for sure how the vaccum function works. From what I can see, there  are four holes surrounding the spindle that act as ports for the suction. Presumably, the oem mat has matching holes that traverse and direct the vacuum to the outer and inner rims (where one can see in pictures holes drilled through). These latter holes would be the vacuum exit points and hence where one's records would be held down. Presumably, one can use other vacuum units as long as the suction power is roughly equivalent. The problem is how to jerry-rig the mat if one doesn't have one.

How do the two compare sonically? I'm going to find out this weekend.

For anyone interested, some guy is selling a brand new in box tt 801 motor unit on Yahoo japan. For a very reasonable price IMO. There can't be too many of those left in the world. No affiliation.


The vacuum platter and pump was an option with the 801. With the Micro the pump is necessary because of the air bearing but you obviously don't have to use the vacuum.
The airflow paths in the Victor TT801 are visible here
http://audio-heritage.jp/VICTOR/etc/tt-801.html
My suggestion would be to replicate the rubber mat in delrin which is easy to machine.
There is also a TT801 vacuum pump on Yahoo Japan at the moment.


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).
I am only going by what vintage knob has to say. I can't swear to how truthful their statement is. It's obviously an opinion but justified by the evidence presented.
http://www.thevintageknob.org/jvc-TT-801.html

"The TT-801 is an extra-rare LP drive and the culmination of the well received but earlier TT-101.
The engineering and bi-directional dual FG servo are the same, even if implemented more discreetely as 1981 allowed more ICs and chips - which isn't necessarily better for long-term servicing."

As far as the vacuum system:
"The Turbo Disc Stabilizer System isn't that different from the one used by Luxman/Micro, but the latter allowed to put the main bearing much closer to the spindle.
The complete system consisted of the TT-801 drive, the TS-1 air pump (optional) and CL-P10 base, with blank or pre-drilled CL-P1D, CL-P2D and CL-P3D armboards."
However, the TS-1 could be adapted to the QL-A95 integrated turntable.
Since the Victor TT-801 was never exported, it never was named JVC TT-801 but only Victor TT-801.

The 801 looks different than the 101 also.
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.
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.
Thankfully I remembered that Lew had 'cornered the market' for the only unobtanium chips used in the TT-101....so after 6 months of stalled frustration......Thuchan's 'junk' TT-101 which I had found for him, is now operational.
And after the complete re-build which his Bavarian craftsman has performed.....it may well be the best TT-101 in existence.
I've offered to buy it from him should he not like it...👅🎼