Technics SP-10 mkII speed adjustment question


Hi,

I'm on my way to complete my Technics SP-10 mkII project. Actually, a friend of mine, a professionnal audio technician, is working to upgrade the PSU, which is done but a small adjustment on the speed must be done and he need some cue on this issue.

We already asked Bill Thalmann, Artisan Fidelity and Oswald Mill audio. Plus, I'll post on DIY Audio today. We'd like to get the answer as quickly as possible to finalized this for the week-end. Hope someone on Audiogon can help.

Here's the message from my technician:

"Hello,

I'm an electronic technician and I do repair for audio equipments, vintage, hifi pro and more. I have a client here that brought me his turntable Technics Sp-10 MKII to fixed. I have a little question about it and he gave me your email because he pretended that you have some experience with this kind of materiel. So, hope that you can response my technical question.

I replaced all capacitors in the power supply and a big solder job. I checked for defect solders or capacitors on the circuit boards inside the turntable and I tied to do the adjustments . Everything seem good right now, the turntable work fine. I tried do do the period adjustment with the VR101 and VR102 potentiometers like in the service manual ( see attachment, Period adjustment method). When I looked the stroboscope at the front of the turntable, It's pretty stable but I can see a tiny rumble at 33 1/2 and 78 speed. 45 is the more stable speed for the stroboscope. So, I fixed the phase reference with T1 at 18us of period and I try to do the period adjustment at the point test T and S on the board with the O point for reference. When I put my scope probe on the T point, I can observe the stroboscope running. It is not stable at all. If I pull off my probe, the stroboscope is stable again. So When I have the 2 probes at point S an T at the same time to do the adjustment, it's impossible to fixed the wave T because it going right to the left on my scope. When I turned the VR101, the T wave going faster or slower but never stable. I tried to ground lift my scope, plug it into the same power bar and try to pull off the reference at the O point. I can't have a setup that I can see a stable T wave in my scope with the one that I can do the right adjustment. Why? Is there a problem with the turntable or maybe it's a incorrect probe or ground setup? Please let me know what you think.

Best regards"

Thanks for help,

Sébastien
128x128sebastienl
Yes Lew, I realized and wondered about the same point after posting this time.

So not to put words in Technics' mouth, perhaps they were referring to the 500 tone arms just as an example. That was wild enough without suggesting 2,500 arms could track simultaneously at 2 g. each without impacting speed performance!

But it clearly states a load torque up to 5 kg cm.

Again, I might be more concerned with bearing wear over time than speed stability. But I'm not an engineer.
Sonofjim and Lewm,

There is one way to adjust your SP-10 mkII speed, it is with an adjustable capacitor inside the turntable. My audio technician show me where it is and he has adjusted the speed to be spot on. Plus, yes, there is also the quartz that can be also adjusted and reseted.

Sébastien
Back on track with the mat. I'm wondering which were the original turntables designed to used the 4 pounds Micro-Seiki CU-180 mat. If we have those informations, we can have another kind of feed-back by comparing their specs lists. Anyone know about those turntables?

Sébastien
Dear Sebastien, See above the interchange between me and Tim (Pryso). For sure, the MkII was designed around its stock platter and mat. The OEM rubber mat weighs, as I recall a bit less than one pound. (I weighed mine on a kitchen scale, but I can't recall the exact result.) So of course the whole was not designed for a 4-lb mat. However, it is clear that because of the torque-y motor, there is some "headroom" to use a heavier mat. The question is "how heavy"? That is to be determined by the end-user, I guess. I am a bit more conservative than many others and so would not consider going much above 2 lbs. But I think we can agree at least that 4 lbs. is about at the outer edge of the envelope. Lots of people report good results with the MS mat and with TT Weights mats that also weigh 4 lbs, so I am not about to say that it can't work well. Like Tim said, at some point, in addition to speed stability, one also has to consider the wear on the turntable bearing of using a much heavier than OEM mat. FWIW, I used an SAEC SS300 mat on my Mk2, which by coincidence weighs not much more than the OEM mat and sounds a heck of a lot better. Same goes for the Boston Audio Mat2, which I now use on my Mk3.
Hi Lewm,

I think that I haven't express myself correctly. I was meaning that by comparing the specs of the turntables that were designed to used the Micro-Seiki CU-180, there are some chances to see turntables with specs similar to the SP-10 mkII.

Anyway, I respect both parties in this discussion and I hesitated a while between Boston Audio mat and Micro-Seiki CU-180 mat. Inspired by certain critics, I finally commited myself and just bought a CU-180 new in box at a good price.
This said, I'm still interested to try one day the Boston Audio mat.

Sébastien
Sebastien, What turntables, besides those made by Micro-Seiki, were designed for the CU180? If what you have in mind are all the Micro-Seiki ones, keep in mind that they are all belt-drive types. In comparing an M-S turntable to an SP10 MkII, both using the same CU180 mat, you are still comparing apples and oranges. The issues with belt-drive are entirely different. Anyway, by all accounts you've made a great choice.
Lew, while I'm certainly not an expert on the Micro-Seiki line, they did produce direct drive tables as well as belt drives. At least I can't find anyplace to attach a belt on the M-S DD-40 table and arm I have in house. ;^)
You're right, but was that one, or any model in the DD series, ever supplied with the CU180 mat, OEM? They also made the DDX-1000 and DQX-1000, minimalist direct-drive designs that I know for sure were supplied with rubber mats, had relatively lightweight platters.
To Micro-Seiki CU-180 owners:

Do you use your CU-180 nude or with another mat on it?

Sébastien
I just received my Micro-Seiki CU-180 mat and the improvement over the original mat is amazing! I can't believe it. I had to call my friend Francis to tell him the feeling that I've got. It's like moving from a $2000 amplifier to a $15 000 one. I was not ready for this. Imagine, Albert Porter told me that he hesitated at first to go with that mat that, we must admit, is pretty expensive. I bought mine new in box for $680 USD, more than twice the price of the Boston Audio mat 2.

Here's the improvement: better bass response, more dynamic, high that are more present and natural and all these advantages even at low volume. Also, it seems to bring a slightly wider soundstage.

Concerning the speed issue with this 4 lbs mat, I can't notice any significant change. The speed is still spot on. I was expecting the start and the stop motion to be considerably more slower but it is not the case .

I highly recommend that uprgrade to every Technics SP-10 mkII or mkIII owners.

Sébastien
Sebastien, Glad to hear you like what you are hearing. I was just as surprised as you when I got mine. Enjoy.

Sean
No doubt the CU-180 will be a big step up from the stock mat. I think you'd notice similar improvement with the SAEC SS-300 and the Boston Mat ll. These mats you may also want to try in the future. This is one tweak that is quick and easy to perform and as you've already seen the results can be fairly dramatic. At $200, I would still recommend trying the Mat ll. IMO it gives the table a more dynamic sound.
Sebastien, Glad you are pleased. I am quite sure that the CU180 would be a big upgrade vs the OEM rubber mat. (Almost any not-rubber mat would be, I think.) Albert will speak for himself if he disagrees, but I do think he now uses the Boston Audio Mat2, on his SP10 Mk3.
Hi Lewm and Sonofjim,

Yes, I'm considering the purchase of the Boston Audio mat 2 for the future to compare it with the Micro-Seiki CU-180.

Sébastien
Hi Sebastienl and other A'gon members,

Do you care to share information on where to get the Micro Seiki CU-180 ?

Thx in advance.
Hi Tagheuer,

I bought my Micro-Seiki CU-180 from 2juki, based in Honk-Kong. He is a regular seller on eBay and already sold on Audiogon. I also bought from him a SME 312S tonearm and a Denon DL-103R cartridge. I was very satisfied with my transaction of the SME and the Denon. Good communication, fast shipping, extremely well packed and at a very competitive price.

For the Micro-Seiki CU-180, two persons reported that he already sold fakes one so I asked for pictures. It proves to be authentic with the original box and the Japanese sticker on the mat. It was described as "new in box" but I realized afterward that it has some light scratches on it, impossible to see them on the pictures. Finally, I judged it to be in very good condition, but it was not mint and it makes an incredible improvement in my analogue set-up.

Regards, and like Raul says, enjoy the music!

Sébastien
Lewm,
"With the modification to the stator mounts, there is less energy dissipated in moving the stators, more precise speed correction by the servo, and far fewer events that trigger the servo. Everything gets even smoother than it was."
But you questioned whether I could hear the error correction on the DD's, even on the "inventor" of these SP10mkIII mods system whose TT I have heard and am underwhelmed.
Halcro,
You need to denude yourself and go and sit on a crowded beach. Open your mind up. It seems clear to me that the gist of the suggestion was the amount of error correction could be reduced by providing a more stable mount for the stators or whatever. If you hear a difference from the removal of extraneous bits, as you proclaim, then why could there not be an improvement from altering the structure or support of those extraneous pieces and other essential components. Your use of referential authority in dismissing Lewms suggestions is not a persuasive argument. I sincerely hope that if you have had design input into bridges in Oz that you have considered the ground upon which they sit. I do have some dear friends over there.
Yo
Dear Halcro and Dover,
I am trying to reconstruct each argument.
Halcro, you seemed to infer, back a few months ago, that a plinth cannot have much effect on structural rigidity of the Mk3, because of the way its spindle/bearing housing is supported within the chassis proper. Ergo, Newton and his 3rd Law go out the window. Is that a fair re-statement of your thesis?

Dover, It seems you are supporting my side, but you are also arguing with something I may have written earlier about whether you can hear the speed correction going on with a servo mechanism. Did I say that? Have you really heard the very same Mk3 that was originally modified a la what Bill Thalmann has recently done with Albert Porter's Mk3? (Bill did tell me that part of the cost of the modifications is due to some financial arrangement with their inventor.) And are you indeed saying you disliked the sound due to an aberration you attribute to audible action of the servo? I hope I was not so presumptuous as to say you cannot hear what you say you hear. I do hear a slight coloration with a fully serviced SP10 Mk2, but I cannot necessarily attribute it to servo action. However, I hear no coloration at all, or less than with any other tt in my memory, with a similarly prepped Mk3, in my slate and wood plinth. That's just me reporting my own observation, not gospel. Your re-statement of my description of the effects of the latest mod to Mk3 (and Mk2, if so desired) is spot on, by the way.
Hi Lewm,

Regarding the modifications discussed above:

"Albert is ecstatic about the new modifications, but he really did not know much about what was done. I then talked to Bill about it. Mostly it is about dampening vibrations and firming up the stator supports. Bill notes that as the servo system corrects for speed errors, some of the energy of the motor is used up in micro movements of the stators, predicted by Newton's Third Law (For every action, etc...) (Ideally, all motor energy would go into moving the rotor/platter.) These tiny wiggles of the stator then in turn produce a tiny correction error sensed by the servo, which senses the fact that some of the torque went into moving the stators instead of the platter. This begets another correction from the servo. And so on. With the modification to the stator mounts, there is less energy dissipated in moving the stators, more precise speed correction by the servo, and far fewer events that trigger the servo...."

Do you know if you can do them on the SP-10 mkII?

Sébastien
Bill can do it for the Mk2 as well. In fact, for some reason the cost is much less vs the Mk3. Ask Bill.
Lewm,
I've known the inventor of the mods for 25+ years and have followed the development of his system. Unfortunately there are many issues with his system outside of the turntable with which I have issues so I have to judge that particular SP10mk3 in that context. As the TT is in constant development I may or may not have heard his latest mods.
I also have other personal friends who number between them another 2 SP10mk3's and 3 Kenwood LO7D's in various states of mods for reference.
I have heard the Denon DP100M back to back with my own Final Audio, but unfortunately it included the integral Denon arm and the sound was not good, I suspect due mainly to the arm.
Back to the SP10mk3, I am not writing it off, due to the constraints under which I have heard it, but have not yet heard anything on 3 samples that leave me with a feeling that I must have it. With regard to the SP10mk2 I have no interest as it is so far off the pace of the mk3 and even the L07D that any time invested would be wasted time in my view. I would estimate that I've heard about 10-12 SP10mk2's over the years.
I should add that when I say I've heard a product, that means I've listened at length in a system I know reasonably well and feel qualified to comment.

Dear Dover,
I hope you did not think I was attacking you for not liking the Mk3. Of course, you are entitled to your opinion. Nor would I care to make the effort to change your mind. But I am interested in what you know about the Mk3 mods that were done by Bill to Albert's Mk3. Can you describe them in any detail? For one thing, I am curious about what is done to the power supply module. For another, I wonder whether the inventor is supplying some actual parts to Bill, for him to effect the modifications. Also, where do you live? Seems you are somewhere outside the US at times, other times not.

Just for my own curiosity, can you say what turntable(s) you do like and also describe the remainder of your system? My system is posted here. Thanks for your input.
Hi Lewm,

Funny, I was just about to ask Dover what's his reference turntable.

Have a nice week-end,

Sébastien
Lewm,

Regarding
But I am interested in what you know about the Mk3 mods that were done by Bill to Albert's Mk3. Can you describe them in any detail? For one thing, I am curious about what is done to the power supply module. For another, I wonder whether the inventor is supplying some actual parts to Bill, for him to effect the modifications.

Nothing is done to the power supply beyond Bill's initial rebuild. My suppy remained here during this last upgrade, so no way anything was modified beyond the motor chassis.

Also, regarding Dover
I've known the inventor of the mods for 25+ years and have followed the development of his system. Unfortunately there are many issues with his system outside of the turntable with which I have issues so I have to judge that particular SP10mk3 in that context. As the TT is in constant development I may or may not have heard his latest mods.

I viewed images of the MK3 that Richard owns and if I had not been told it was once a Technics I would not have recognized it. I have no idea if what was done makes it better or worse than original or how that fits with the mechanical mods he came up with.

Richard told me he was using Acoustat 2+2 speakers and all his electronics were built by him. Further separation from mainline components that one might use to judge total system performance.

For those reasons I'm not sure I could tell anything about the MK3 or any other table that might be put in play. Not saying there is anything wrong with what was done, more like listening to a system at a show where nothing is familiar and trying to offer an accurate assessment.
Thanks, Albert. I thought I had been told that there were some mods to the outboard PS associated with your upgrades. I was obviously misinformed, or my memory is playing tricks. Is "Richard" the guy who invented or first devised the beneficial modification(s)? Even Dover admits in the quoted paragraph that he is unable to make a judgement regarding the modified MK3, because so much else about the system is in constant flux.
Is "Richard" the guy who invented or first devised the beneficial modification(s)? Even Dover admits in the quoted paragraph that he is unable to make a judgement regarding the modified MK3, because so much else about the system is in constant flux.

Yes, Richard Krebs came up with the mods and worked out with Bill Thalmann to perform them stateside so customers don't ship all the way to NZ.

Richard told me he spent over fifteen years developing the mods and he (smiling) said he wish he could have been here to audition before and after the effect of the mods.

Seems he spent so many years developing it was always a bit at a time rather than all at once I experienced.

The mods are quite excellent and as I've posted before provided results that were completely unexpected. I was thinking quieter, more refined, more black background and instead heard drastic reduction in distortion, greater detail, better dynamics and opening up (greater transparency) of all frequencies but without any hardness or shrill added to the extreme highs.

What I'm looking forward to is someone doing the less expensive SP 10 MK2 mod. It would be interesting to hear how that goes up against a "stock" MK3.
Lewm,
Not offended at all. I have learnt a lot from the various verbal jousts. I'm a great believer in learning what not to do is equally as valuable if not more so in learning what to do.
I dont dislike the SP10mk3, for me the jury is out until I can hear one in my own system. Its on my to do list.
The SP10mk3 upon which Alberts latest mods are based, last I heard it, is mounted in an acrylic/lead/acrylic sandwhich, runs an ET2 heavily modified with custom acrylic manifold & other tweaks, and Shelter 901. The main issue for me are the speakers, Acoustat 2+2 heavily modded in a room that is barely 10ft square. The system in question for me lacks timing, cohesion and transparency but as you know this is a sum of the parts and I would not necessarily ascribe this to the TT.
Albert in an earlier post alluded to power supply mods, and not including the bearing mods, hence the confusion. I cant give you any more insight, but in terms of product improvement in general, you just keep working on the weakest points. It would appear that the latest mods as you mentioned above are more around stiffening up main chassis and mounts.
It would seem to me that reviewing the Kaneta and Cotter mods are quite thought provoking. Looking at the cross section Halcro provided a link to indicates that perhaps opportunites exist to not only stiffen up internal mounts, but decouple or eliminate as much as possible from the main bearing and motor.
If it comes to that, I like what Steve Dobbins did to Mike Lavigne's Mk3, removing the motor entirely from its chassis and imbedding it in a solid plinth. I would be reluctant to do that with my Mk3 for fear of diminishing its value, and because it was NOS when I got it, kind of an historical object that also plays music. This did not prevent me from going all out with the plinth design and construction, however. I have held off on the Thalmann mods because of cost. Eventually, I will likely cave in and get it done. The Cotter and certainly the Kaneta mods pertain to the Mk2 only, I think. Also, I think Halcro's objection to the SP10 construction is relevant more to the Mk2 than the Mk3. (Maybe that will get a rise out of him.)

So, can you say what turntable(s) you do favor at this point in time? I myself am not ready to say that the Mk3 is clearly a winner vs the tweaked L07D, at least not yet. For sure, I could live happily with either one.
Lewm,
The Dobbins treatment is not an irreversable step. He did the same with one of my mkllls and sent me back the chassis housing which can be reinstalled with about 3 bikes work he tells me. Not that I ever will but good to know. It's a great performer in it's current form. I also am soon sending my other MKlll to Bill for the Krebs mods so within a month ro two can compare. I expect roughly equivalent performance. We'll see.
Sorry, that's 3 hours work. I'm on a weekend bike ride to benefit MS with my wife and must subconsciously have bikes on my mind.
That's pretty funny, actually.
The main reason I am tempted by the Dobbins approach is that it allows a much wider choice of tonearms. The stock Mk3 chassis gets in the way of most 9-inch tonearms, and on the wide sides (rear and left) one would be hard-pressed to mount and align properly anything but a 12-incher, surely at least a 10-inch is minimum.
That's one of the best things about the sp-10 tables IMO, their flexibility. As far as the desecration of an heirloom goes, I look at these as my long term tables. I bought them to use and if I can do something to improve the performance it make sense to me. I haven't heard a table that sounds better when these are well implemented. I don't believe either Bill's mods or Dobbin's will decrease the financial value. I see Dobbins plinthed MKllls sell for similar prices to the spec variety. It was really the fact that Steve told me the process could be reversed that convinced me to go ahead with his. It's about the quietest most solid table I can imagine. I really wouldn't be surprised if Bill's mods accomplish very nearly the same result. I don't think you could go wrong either way. I'm not sure what table Dover must have if he finds the mklll uninspiring. It must be an awesome machine. Good for him if so. Meanwhile, I can't imagine being happier with my own situation .
I too asked Dover what turntable he currently favors, but the question remains unanswered. I suspect that Dover does not want to get into an argument about direct-drive vs some other technology that he may favor, and I don't blame him. I can only assure him that I am merely interested to know what he likes, because I respect his judgement.
Well same for me. I think that's also interesting to have somebody's reference to better understand any critic formulated.

I too respect everyone choice. After all, they are personnal preferences. In the audio world, you have components for every taste.

Sébastien
I came upon this old thread whilst searching for more specific information about the Krebs SP10 Mk3 modifications. Suffice to say that I can find none on the internet, aside from the generalities revealed in this thread. My interest is piqued because I am now finally considering having my Mk3 re-seated by Steve Dobbins in one of his plinths. It would seem that Steve's approach addresses all of the same issues as those addressed by the Krebs mods and for me also makes it much easier to mount two tonearms of any type for use with the Mk3. (I wrote earlier of the fact that the stock square Technics escutcheon surrounding the platter pretty much interdicts the use of anything but a 12-incher as a secondary tonearm.) I also have resolved to cut back on the number of turntables I own in the process, since I have decided that the Mk3 and the L07D are supreme.

So, Sonofjim was about to be able to experience BOTH the Dobbins Mk3 and the Krebs Mk3 in his home system. Tell me, what do you think by now? Pinging Sonofjim...
Lewm,

Sonofjim has not heard the Krebs mods. His comment about Bill Thalmann mods and Dobbins mods referred to electronics.

There are (to my knowledge) only two people capable of doing the Krebs mod. Richard Krebs in NZ and Bill Thalmann in USA.

I had Richard in my home for a week, I'm pretty sure this information is accurate.

I have NO financial connection whatsoever to either of these mods or shops other than being friends with both.
Albert
Thank you for clarifying this. You are quite correct, only Bill and I know how to do the Krebs upgrade.
Dear Richard and Albert, As you both know, Bill Thalmann would be the one to upgrade my Mk3 with the Krebs mods. (Until 2 days ago, I did not know Mr. Krebs' identity. Nor did I know enough to credit him; now I do.) Bill's shop is about 30 minutes drive from my front door. Perhaps I was misunderstood to have stated that Dobbins does the Krebs mod. I only meant to say that it would appear that both approaches (Dobbins and Krebs) are targeting the same issues as regards the operation of the Mk3 motor and servo system. I fully realize the methods may be very different. I am curious to learn more about the specifics of the Krebs mod, as Richard knows from our recent private correspondence.
I guess I will ask another question and also bump this thread. Albert, did you have any truly objective way to know that the Krebs mods made a significant improvement in your Mk3's performance? Or are you reporting a subjective impression, which is perfectly OK?
Lewm, if you are looking to potentially use a Dobbins plinth for your Mk3 you can check out my add for Mike Lavignes original plinth.
12-09-12: Lewm
I guess I will ask another question and also bump this thread. Albert, did you have any truly objective way to know that the Krebs mods made a significant improvement in your Mk3's performance? Or are you reporting a subjective impression, which is perfectly OK?

I've had several MK3s. Two here now, one of which is beyond totally restored and for sale here at Audiogon.

When my MK3 got the electrical upgrade from Bill Thalmann the Krebs mod was not available. I had hundreds of hours to listen since my first MK3 and I've tested over and over the effect of plinths, mats, clamps, damping, isolation and tonearms.

My Krebs mod was gotten to quickly as mine was first in line. We still had the other table here as well as my ultimate reference of Studer tape and collection of master dubs.

The first 30 minutes with Krebs mod was such a surprise I could not take in the experience. Not that it was difficult to hear the difference, quite the opposite. My shock was the AMOUNT of difference this made.

I'm going to go out on a limb but the Krebs mod might be a bigger upgrade than going from Technics MK2 to Technics MK3.

As time has passed the upgrades improved. I know why since I have some knowledge of what is involved. However, unless Richard chooses to share "why" I will not go into that.

Based on the massive copy cat designs fostered by my Panzerholz plinth (soon to be 5 years ago) I can understand why Richard and Bill might be mute on the topic.
Lewm et al,
If you look underneath your Kenwood L07D you will find the archilles heal of the Technics SP10mk3.
Dover, I think I know what you mean. The L07D represents a very different approach to direct-drive, compared to the Technics one. IMO, the L07D is vastly under-rated compared to the Mk3, which is not to say that the latter is not superb.

BFalls, I responded to your Audiogon message. Evidently you did not receive it. Audiogon may not want us to talk privately.
The Technics SP10mk3, Victor TT-101, Denon DP80 are all what I would call upside down turntables. That is they are designed to drop into plinths and the motor/mainbearing assembly hangs like dogs balls below the plinth - waving in the wind. The connection points to the "plinth" are on a flimsy exoskeleton/cover into which the motor/bearing are screwed.
The resultant structure lacks rigidity and the path for energy dissipation from platter to ground is compromised. Its a labyrinth from the platter to the ground, and the unstable reference of the tonearm to platter is counterproductive in measuring the groove accurately.
Compare this to the Kenwood L07D, where there is a massive cast foot underneath onto which BOTH the motor/bearing AND armpod are BOLTED.
see
http://www.l-07d.com/plinth.htm
This is a far superior construction in my view in maintaining rigidity between the arm/platter and the platter/turntable/arm/cartridge loop.
If you check out the Exclusive P3 this also has a motor/bearing/arm mounting system with a superior motor/bearing/arm platform that correctly references the arm to the bearing/platter. see
http://audio-database.com/PIONEER-EXCLUSIVE/player/p3a-e.html

The Denon's use a decoupled platter arrangement to keep motor energy way from the cartridge, but they do not address the lack of rigidity from the upside down design.

In my view any serious attempt to replinth theSP10mk3 would include throwing away the exoskeleton and motor covers and bolt the motor, bearing & tonearm mounting base rigidly to a common subchassis to maximise rigidity and minimise any potential movement within the platter/turntable/arm/cartridge loop.
I'm sure dropping the SP10mk3 into a slate or panzerholz "plinth" makes a difference but it is only a half pie solution in my view.
All points well taken, altho thankfully all of the turntables you mention are more attractive than the metaphor you chose to describe them.
In my view any serious attempt to replinth theSP10mk3 would include throwing away the exoskeleton and motor covers and bolt the motor, bearing & tonearm mounting base rigidly to a common sub chassis to maximise rigidity and minimise any potential movement within the platter/turntable/arm/cartridge loop.

I'm sure dropping the SP10mk3 into a slate or Panzerholz "plinth" makes a difference but it is only a half pie solution in my view.

You have obviously not studied what was done with my version of the MK3 plinth, Panzerholz plus metal interior plate attached to the MK3 using stainless steel bolts.

Underneath there is a large steel plate with stainless bolts through the chassis and metal plate, into the MK3 carriage. A large non magnetic threaded brass rod attaches to the bearing and undercarriage capturing the Technics from any vertical movement and provided a sync for vibration.

The arm boards are attached with stainless steel plate, attached with stainless steel screws and fixed to the same plate as the chassis of the MK3.

This is 90 pounds (+) of "cure' for what was originally supplied by Technics. The sorry "glass" plinth by Technics was a joke and none of the tables you list has a plinth with even a fraction the effort and material that was put into ours.

Last, the top plate of the MK3 does not matter one whit once the other issues are resolved. In my opinion this is simply an easy way to purchase beater SP10 MK3 and not have to repair or restore the damages chassis parts to make it presentable.
Hi Albert -
I refer to panzerholz or slate plinths in general - not yours.
I have no idea what your plinth or the Artisan Fidelity does. That you have addressed many of the structural issues within the Technics as opposed to just "cutting a hole" underpins the thrust of my post to highlight that to replinth is not a straightforward task - one has to understand the pros and cons of their TT design from top to bottom, inside and out, before they start planning a major upgrade such as replinthing.
The purpose of the post was to get people to look deeper and think more deeply about their TT in order to improve it. Much of the work required is documented on the net.
In Lewms' case he has to make a long term decision whether to keep his NOS SP10 relatively stock, or gut it, but if you are going to gut it, why go half way.


Understood and I agree. There are many plinths for sale that are nothing more than a cookie cutter hole in a piece of material. Hardly a proper plinth.

As for Artisan Fidelity, their plinth is a copy of mine and I resent that. However there are others and probably will be more.

My Audiogon Lenco project is here: http://forum.audiogon.com/cgi-bin/fr.pl?vbudg&1082337040&view

That was nine years ago, but I built dozens of plinths and worked with high end turntables thirty years before that post first appeared.

I agree most people don't address rigidity and that is perhaps the most important thing other than quality of materials.

The other people that put everything they know into making their plinth right is Steve Dobbins and Oswald Mills. All of us do it a bit different and each gets a bit different result but those are all originals and represent maximum effort.