Upgrades for a Thorens TD 126 MKIII? (vinyl newbie)

[user510]

No, no parade rainin'. The OP had actually done OK. This is AudioKarma's TT forum and the first place flippers and opportunists come to check the market vibe before they stick an overpriced tag on their epay / CL latest estate sale scores. The truth must be told to restrain those who operate out of greed and try to exploit those who do it out of love.
Exactly! When I mentioned "unfavorable" those are the models that pop in mind. Ever compared their PCB's and components to the early classic Thorens models like the TD-125 or TD-145??? These newer ones look exactly like their Japanese counterparts with cheap low qauality electronic components purchased by the hundreds of thousands from the lowest bidder. Gone were the European parts, like the Fraco PS and Philips phase shift capacitors and none of the exemplary circuit designs survived. All remains of left over quality from the golden era vanished by then, only to be replaced with lots of plastic by bean counters cut backs and savings... It's no wonder they went bankrupt!

And yet owner reports on these turntables tend to be favorable.
The TD126III remains top of the line in terms of build quality while incorporating a new motor with a then new circuit design to control it.
I think naysayers need to have actual hands-on experience with these before tossing verbal rocks at them. Likely it would change their minds and cause them to take another look at their existing turntables through a new perspective.

re: Thorens bankruptcy. That did not happen until the turn of the century. And there were some very interesting models produced during the late 1980's and early 1990's. Think of the Td2001, 3001 and Ambiance for example. The innovation never stopped until their accountants indicated it was time to close the door. And. btw, their motion for bankruptcy was denied by the German govt. The solution / salvation came through the purchase of the company by the current owners. So...even though the product line changed considerably after the change-over, the company remains in business with new different leadership.


-Steve

 

[bang4buck]

@tnsilver -- just so YOU'd be aware, the target of your tirade runs http://www.theanalogdept.com/. Which you would know if you had paid attention to previous posts.

 

[Dan ʕ•ᴥ•ʔ]

Let's try to keep it friendly and polite, people!

 

[Blue Shadow]

They information that Steve and Tom are discussing is interesting and valuable to those wanting to learn about the different models. The attitudes being used to convey this info...I'll just read past it and not worry about that part. I have used helpful information from both of them to keep my machines and others TDs right. I've had a TD-125 II B, a TD-160 Super, TD-165 CL buy but I didn't like it and parted it and now a TD-125 B. Would get a 126 if one showed and it is good to read the differences that make the available Mks worth considering or concerning depending on the version.

 

[dinger]

I was gifted a TD 126MK III from my brother in law and have been enjoying it for a few years now. There's a lot to like and a lot to quibble about with this table. I've ended up disabling all the automatic arm handling with a very sketchy mechanical system I was not able to comprehend let alone help recondition or adjust properly. That leaves the platter spinning as its only strength and there I'm not the least satisfied either. It seems to continually hunt & adjust the speed.

Other than that, as long as I don't obsess about the strobe I really enjoy listening to it.

 

[tnsilver]

It seems to continually hunt & adjust the speed.

Sorry to hear about that. That's most likely exactly what's it's doing. It's a common issue with these turntables and very characteristic of the DC servo motor and it's supporting circuitry. Unfortunately, that beast is too elaborate for the solutions to be as common too. It's most likely that 40 y/o components, like EC's and resistors had drifted out of specs and that tarnish had developed at IC's pins and near their supporting RC networks. I'd not rule out some dead solder joints as well, and I'd suspect the fine speed adjustment pot and all the internal trimmers require thorough cleaning. Of course, speed drifts could also originate internally from the motor, with poor brush contacts and even from the motor I/O wiring. It may also, in low likelihood, relate to a greasy drive belt path. There's just too many things to go wrong, too many sensitive IC's pins to verify voltages and wave forms on and too many mechanical culprits. Trouble shooting this is too time consuming, parts are scarce and the mechanics quite complex. One can spend hours just calibrating the auto shut-off induction sensor at the base of the tonearm. This type of DC servo motor drive and it's supporting circuitry is disliked for a reason and not only by techs and DIY'ers. It doesn't look like Thorens liked it any better, so the DC servo motor concept was dropped in the following mark. If you want to get it fixed - find a (very) good tech and be prepared to pay for his time. Lot's of it. If you tinker with it - you'll most likely just make things even worst.

 

[user510]

I was gifted a TD 126MK III from my brother in law and have been enjoying it for a few years now. There's a lot to like and a lot to quibble about with this table. I've ended up disabling all the automatic arm handling with a very sketchy mechanical system I was not able to comprehend let alone help recondition or adjust properly. That leaves the platter spinning as its only strength and there I'm not the least satisfied either. It seems to continually hunt & adjust the speed.

Other than that, as long as I don't obsess about the strobe I really enjoy listening to it.

Good video. I saw some hunting at the strobe on mine as well, but it seems to settle down and hold steady once all warmed up. Whatever I see during this restoration process on my sample will be reported at my site. Likely I'll begin in a month or two, once a couple of other items are complete.

I see nothing to be gained in arguing the merits /demerits of this particular Thorens motor/controller design. All I can say at this time is that the SQ is quite good.

Logging off for now.
-Steve

 

[dyche01]

What, no photos?

 

[bang4buck]

I was gifted a TD 126MK III from my brother in law and have been enjoying it for a few years now. There's a lot to like and a lot to quibble about with this table. I've ended up disabling all the automatic arm handling with a very sketchy mechanical system I was not able to comprehend let alone help recondition or adjust properly. That leaves the platter spinning as its only strength and there I'm not the least satisfied either. It seems to continually hunt & adjust the speed.

Other than that, as long as I don't obsess about the strobe I really enjoy listening to it.

I wouldn't take that 35+ year old stroboscope for the gospel truth. How's the strobe light generated in these? I hope Thorens engineers were smart enough not to run the light off the same circuit that drives the motor.

If it runs on line voltage, you may want to try it at different times of the day. Part of what you're seeing could be line frequency fluctuation.

 

[user510]

What merits? With speed instability SQ is as good as the listener can tolerate it. It definitely isn't as good as the recording. It boils down to personal taste and experience or more likely the lack thereof. I just wonder... if speed isn't that important and SQ is independent of it, does one really need a hefty, expensive Thorens?

It does not sound like speed instability at all. Actually, and to my ear, it sounds as though it is 'very' speed stable. And I base this subjective impression of mine on recent experience with an SP10 mkII, which also exhibits that sense of speed stable correctness.

At this point I'm not ready to start throwing rocks at the design. yes, I have read other negative comments around the web on this model. Rather than just get on the bandwagon with the naysayers, I will make my own observations and draw whatever conclusions that I do based on actual first hand experience. bang4buck's comments deserve some examination, at least in reading the schematics of the power supply and speed control circuitry.
Here's a link to a TD126-III I have at the site:
http://www.theanalogdept.com/images/spp6_pics/TT manuals/Thorens/TD126 MkIII.pdf
While the text is in German, the schematics will be readable to those already practiced in the deciphering of them regardless of language spoken.

-Steve

 

[bang4buck]

Thanks for that! The strobe light is running directly off of line voltage, bottom left of the schematic.

So, looks like there really is speed fluctuation going on in dinger's unit. Ideally he would test it with an independent quartz-regulated strobe such as the one that KAB sells but those are over $100 and frankly, it's more likely to be the motor circuitry.

 

[user510]

Thanks for that! The strobe light is running directly off of line voltage, bottom left of the schematic.

So, looks like there really is speed fluctuation going on in dinger's unit. Ideally he would test it with an independent quartz-regulated strobe such as the one that KAB sells but those are over $100 and frankly, it's more likely to be the motor circuitry.

OK. Thanks for looking into it!
On my unit the strobe does become evidently stable once the table has been in recent use. for instance when it gets played daily and routinely, the strobe does not exhibit any hunting. Once set, it stays that way. And it will remain stable throughout even the longest listening sessions I do. I presume that the unit I have will require replacement of its capacitors due to the rather limited life cycles we now understand these components to have. Figure 1977 to 2018 is 41 years out of the factory. New caps are part of the plan for my unit.

-Steve

 

[bang4buck]

I meant to add that within reason I'm happy to translate parts of the German manual for any of you. I'm German but I'm not an electrical engineer.

 

[bang4buck]

@dinger - May I ask where you are located? Is it possible that you have unstable line frequency? This does happen. Just a few weeks ago alarm radios all over Europe were up to six minutes off because they keep time using line frequency, which was suffering from a dispute somewhere in Romania or thereabouts.

 

[dinger]

I get power from CMP (Central Maine Power Co). I read it's not uncommon for line freq to vary .5hz from time to time. Thanks for all the other ideas about what may be causing the catch and release effect i'm seeing. If the line freq is steady, then it seems to be waiting too long to add power to maintain speed. So there may exist a condition of "not enough feedback" which would make sense with components out of spec. If anyone has suggestions on devices to check I'm a technician by trade and can investigate. It would be nice if someone could assure me the MKIII was capable of rock steady speed when new. I'm leaning to give the motor a pass as it's spinning multiple X faster than the platter.

 

[tnsilver]

If anyone has suggestions on devices to check I'm a technician by trade and can investigate

You can try to clean the fine speed adjustment pot with contact cleaner and exercise it, and to do same for all the internal trimmers. Remove any tarnish around IC pins and refresh solder joints. Replace all the 7 or 8 electrolytic capacitors and very meticulously check the values of resistors in RC networks around IC's to replace the out of spec resistors. Follow the schematics and make sure the power supply outputs the specified voltage (IIRC 12VDC). It's a shot in the dark and after you do it you'll need to verify voltages on most pins of most IC's inside that turntable and adjust them as per the service manual. Pass on the motor as planned. DC servo motors are not only fed power, they also output speed feedback and this one has 4 wires attached to it for that purpose but also a tachometer. It doesn't matter how fast it spins, it's never constant and there's little you can do about it, motor wise, so just hope it's got nothing to do with the drift. Watch out for the strobe - it's fed live mains voltage! There's very little chance you'll fix it like this, and there's much to do! However, if you're a tech with basic electronics skills (or better), it's at least worth a shot comparing to the expensive alternative.

 

[thought91]

he table is fine as it sits. If you have money burning a hole in your pocket, I would spend it on either a phono stage upgrade...depending on which one you are using. Or I would spend the money on a way to clean your records. Clean vinyl is one of the best upgrades you can make. For the cheap, i would use something like the Vac Wand, or some sort of vacuum based cleaning machine. Don't know what is available in your area, but in North America the Squeaky Clean machine is the most affordable option. Not sure if you got anything there that is the equivalent.

I'll look into that, thanks.

True. The DC servo motor used on this table departs from their previous methods. But.....they gained more power to the output while not adding any cogging attributes associated with previous motors that were used. This motor was also used on the TD105, 110 and 115 models during the same years of mfr. So spares, while not plentiful, can be sourced.

Here is something that the Td126 mkII or previous mk1 or the Td125 models can not do.....it can start from cold and reach calibrated 33-1/3rd rpm in less than two rpm. It is the increase in torque and power output that makes this possible. You can also hear this added output power in the sound, where rhythmic drive has a stronger motivation.

All the while it retains one of the industry best signal to noise ratios of that day....which continues to be supurb today.

So I guess I reveal some enthusiasm that I feel for this particular model based on the experience that I have had with it. In time, as I work with it, I will document my observations to my site. Both the positive and negative. Presently, my sample is in good form.

-Steve

Interesting, thanks for the input.

Consider a cork turntable mat which benefits the sound enough to make a difference....

I saw a cork mat on a Linn the other day and thought I'd buy one for the Thorens. Will definitely get to that, thanks!

Is it working correctly? Does it have the stock tonearm?

No idea, I'm picking it up today, so we shall see.

Thought91 you didn't half step, that's a big leap for your first table. I checked the listing on Ebay and according to the dealer/seller it has been checked out by his tech and is in good operating condition. I'd speak with the dealer to see if the belt was changed if it needed it and the bearing lubricated, both simple fairly cheap maintenance items. Being a top Thorens model it shouldn't need anything as far as upgrades go other than maybe a cartridge. I'd leave the M97 on it until you get very comfortable operating the table. You might want to update what you have for a preamp etc. I'd save the balance of your funds for record cleaning equipment/supplies that will have a lot greater impact on sound quality than most upgrades like changing mats etc. As suggested download/printout the owners/service manuals from Vinyl Engine. By the looks of it you did very well on the price, when you transport it home I'd have the dealer remove the platter to be safe.

I think that my current preamp is more than sufficient. I'm very happy with the rest of my system. In my room, I use Vandersteen Model 3's, a Nikko Alpha 1 and Beta 1, (Vandies bought for 450 and Nikko bundle bought for 350. I've read that the Beta 1 has a good phono stage, so I guess it'll do the job.

 

[thought91]

Thought91 I was going to recommend that you purchase the Thorens but you beat me to it by making a hard to beat "best offer". This was an ideal situation for you where the seller didn't want to ship the table and you were very smart to take advantage of the situation. The Thorens TD-126 was one of Thorens upper tier tables and it is unlikely Thorens took any short cuts back then when they designed/ built the table including the mat. As more experienced AK members have suggested leave it in stock form for now, at best another mat might sound different but unlikely better than the factory mat and all you will succeed in doing is wasting your money. For many that TD-126 would be an end table but you jumped to the head of the line on your choice of a first table, to get a table of that build quality today you would probably have to spend close to $2,000. I agree with Bimasta that the Thorens is a much better choice than the Linn, as your farther experienced you would end up bankrupt with that money pit of a table. I can't over emphasize that a turntable is very delicate and has to be handled with extreme care. As another AK member suggested have the dealer disassemble the table for transport home, bring a copy of the owners manual to the store when you go to pick it up and have them follow the reverse of assembly using boxes and packing material. Don't hesitate to get back to us for advice re the TD-126, terrific to see a young smart AK member start out with a high quality vintage table that many older AK members would only dream about owning. As for upgrades that make sense keep an eye out for a set of hinges for the dustcover, if you have all the original parts the TD-126 can only go up in value.

Okay, I think I remember seeing a manual on vinylengine. Your input is very much appreciated! I'll be very careful with use, and extremely careful with transport. I must have glazed over your comment in my first read through of the replies, I'll hold off on a new mat for now, thanks!

 

[thought91]

And yet owner reports on these turntables tend to be favorable. (obviously with outiers as seen in this thread)
The TD126III remains top of the line in terms of build quality while incorporating a new motor with a then new circuit design to control it.
I think naysayers need to have actual hands-on experience with these before tossing verbal rocks at them. Likely it would change their minds and cause them to take another look at their existing turntables through a new perspective.

re: Thorens bankruptcy. That did not happen until the turn of the century. And there were some very interesting models produced during the late 1980's and early 1990's. Think of the Td2001, 3001 and Ambiance for example. The innovation never stopped until their accountants indicated it was time to close the door. And. btw, their motion for bankruptcy was denied by the German govt. The solution / salvation came through the purchase of the company by the current owners. So...even though the product line changed considerably after the change-over, the company remains in business with new different leadership.


-Steve

I did notice those who tend to recommend that people stay away from the TD 126 MKIII's seemed to have have never heard one, and that those who have heard them tend to give sparkling reviews.

It does not sound like speed instability at all. Actually, and to my ear, it sounds as though it is 'very' speed stable. And I base this subjective impression of mine on recent experience with an SP10 mkII, which also exhibits that sense of speed stable correctness.

At this point I'm not ready to start throwing rocks at the design. yes, I have read other negative comments around the web on this model. Rather than just get on the bandwagon with the naysayers, I will make my own observations and draw whatever conclusions that I do based on actual first hand experience. bang4buck's comments deserve some examination, at least in reading the schematics of the power supply and speed control circuitry.
Here's a link to a TD126-III I have at the site:
http://www.theanalogdept.com/images/spp6_pics/TT manuals/Thorens/TD126 MkIII.pdf
While the text is in German, the schematics will be readable to those already practiced in the deciphering of them regardless of language spoken.

-Steve

How do I assess the speed of a table?

You can try to clean the fine speed adjustment pot with contact cleaner and exercise it, and to do same for all the internal trimmers. Remove any tarnish around IC pins and refresh solder joints. Replace all the 7 or 8 electrolytic capacitors and very meticulously check the values of resistors in RC networks around IC's to replace the out of spec resistors. Follow the schematics and make sure the power supply outputs the specified voltage (IIRC 12VDC). It's a shot in the dark and after you do it you'll need to verify voltages on most pins of most IC's inside that turntable and adjust them as per the service manual. Pass on the motor as planned. DC servo motors are not only fed power, they also output speed feedback and this one has 4 wires attached to it for that purpose but also a tachometer. It doesn't matter how fast it spins, it's never constant and there's little you can do about it, motor wise, so just hope it's got nothing to do with the drift. Watch out for the strobe - it's fed live mains voltage! There's very little chance you'll fix it like this, and there's much to do! However, if you're a tech with basic electronics skills (or better), it's at least worth a shot comparing to the expensive alternative.

I'm lacking in knowledge, but I'm good at fixing speakers and have fixed one amp competently. If I'm confident in my handiness, but rely on others as a source of knowledge, would you recommend that I give your advice a go if I encounter similar issues or just stay away from trying to fix it myself?

 

[tnsilver]

would you recommend that I give your advice a go if I encounter similar issues or just stay away from trying to fix it myself?

Stay away from it. You need a bunch of lab gear tools for the job and more than basic electronics skills to handle it, or just a serious and generous stroke of luck. A spare motor would increase your chances - but what do I know... I'm the one recommending to stay away from it - remember?

just for the record, I'm talking only about the Mk-III here.