Thorens TD-160 Mk 1 Tune-Up and Setup Project

[Timothy Flath]

VTA/SRA is one of those things I've never really fooled with. I do have my cartridges set up with a repro Thorens alignment gauge and they specify some range of depth from stylus tip to bottom of the gauge as their method of setting it. I did that and so far as I know the arm has never been moved at the back. In theory that makes it all correct per the factory design. I've never put any further effort into tweaking it though.

I think I'd be a lot more inclined to fool with it if I had an arm that allowed on the fly adjustment by simply turning a knob while it played so I could easily listen for any changes. Beyond that requires more effort than I care to invest.

We certainly agree on one thing at least.

 

[Toblerone]

I remember a few years ago a group of us sat and listened to platter mats. I forget how many exactly but it was around 10 if I recall. They definitely sounded different but we didn't control for VTA changes either so there may have been a few factors in play there. People that aren't audio dorks will look at you like you have 5 heads if you tell them you spent an afternoon listening to turntable mats, but thats the sort of insanity we live with.

That sounds like a really fun way to spend an afternoon to me!

 

[Timothy Flath]

Part 5 is now complete. In this part I cover changing the arm tube from a bent one with a NOS TP-16 arm tube that I ordered from SCHOPPER.ch in Switzerland for a very reasonable sum. They bought out a lot of the old stock that was on on hand from Thorens when they went into receivership many years ago I understand. Next I go on to discuss rewiring the arm and then I go on to talk about and execute spring suspension tuning. Hope this is helpful to some.

 

[Timothy Flath]

Part 5 Addendum - amplification on when and how to do the final suspension tuning:

 

[Timothy Flath]

A lttle ditty I did on the TP-60 headshells (as fill until my next part in this series is released):

 

[Timothy Flath]

And of course my 3D designed headshell as an inexpensive alternative to the TP-60 which are getting harder and harder to find at a reasonable cost. These, in my opinion, are absolutely as good as the original TP-60 with no compromise - I use them interchangeably in all my Thorens turntables that use this beautiful and iconic headshell. I make nothing on these and have made the design available for free (on Thingiverse dot com) to anyone out there who owns or has access to a 3D printer and want/need an alternative headshell option. Beware, I have seen several people who have downloaded and printed my design and are selling them on ePray for big bucks compared to the amount it actually costs to print (literally pennies a headshell):

 

[tnsilver]

The replica sure looks nice and as close as it gets to the original TP-60. Nice job! One concern though... The stock one appears to be Magnesium (or some zinc alloy) which was likely chosen to keep some of the key headshell properties like rigidity. How does the 3D replica compare performance wise?

 

[Timothy Flath]

The replica sure looks nice and as close as it gets to the original TP-60. Nice job! One concern though... The stock one appears to be Magnesium (or some zinc alloy) which was likely chosen to keep some of the key headshell properties like rigidity. How does the 3D replica compare performance wise?

Magnesium was mainly chosen for non-mag properties (it is actually diamagnetic if you look it up) rather than its strength IMHO. You can't get anymore non-mag than PLA plastic. I would challenge anyone to bend break or distort one of these PLA shells with bare hands. Chances are the arm tube connection point would fail before the headshell even begins to distort. It is very tough stuff given that the TP-60 design gives it a high degree of rigidity simply due to its shape...
Sound performance is the same to me - if I did a double blind test I highly doubt anyone could detect a difference in sound with any better odds than guessing.
;-)

 

[tnsilver]

I would challenge anyone to bend break or distort with bare hands. Chances are the arm tube connection point would fail before the headshell even begins to distort.

I didn't know that about 3D printing. I was under the impression the material's strength was the weak point. It's good to know!

 

[tnsilver]

Magnesium was mainly chosen for non-mag properties

I'm not sure about that. Aluminum is cheaper if you want just non-mag. Magnesium is lighter, less resonant and stronger, but most magnesium headshells are actually magnesium/aluminum alloy, b/c pure magnesium is rather brittle.

 

[Timothy Flath]

I'm not sure about that. Aluminum is cheaper if you want just non-mag. Magnesium is lighter, less resonant and stronger, but most magnesium headshells are actually magnesium/aluminum alloy, b/c pure magnesium is rather brittle.

Correct in your assumption on the headshell - it is certainly an alloy of Magnesium. Depending on the "other" metals makeup of the alloy, magnesium is actually known to cause interesting properties for the combined materials outside of EMR implications. Didn't want to get into a science class with anyone here. I think you will find that PLA is not very resonant at all. If you are dead set on finding out more please follow the link here (your brain will hurt guaranteed and I have a background in Physics and Engineering):
https://www.mdpi.com/2073-4360/14/3/413/pdf (Probably more than you will ever find on a Thorens headshell design)

Bottom line: You can get as sciency as you want on the subject but I still contend that if all else being equal (turntable, cart, tonearm and stereo system) I can pretty much guarantee you will not be able to tell a difference any better than chance would dictate to differentiate the two IMHO. You can speculate all you want but until you try it for yourself you are doing just that "speculating". Having lived and worked (in a rather amazing hifi shop) near the Thorens factory in Lahr, Germany (Kubach actually) back in the day I became a fan then and there. However, had you ever seen the actual factory from whence these turntables came like I did, you would be highly skeptical of the extreme engineering that people thought went on there. Not saying they were not exceptional but they are certainly not as "Holy Grail' as everyone seems to think. It was very much like a Mom & Pop shoe factory from several very close friends I have known who have toured the place. That is my take anyway. Believe what you will, it is all good...

Incidentally here is the conclusion of that head-hurting report linked above:
Conclusions
3D printing is a developing technology affecting many areas of life. 3D printing technology allows the production of lightweight materials of different shapes and structures compared to other manufacturing technologies, which leads to time and energy savings and reduces the weight of materials.

The purpose of this study was to investigate the sound reflection performance of 3D-printed open-porous PLA materials made with four different types of porous structures. In addition, the investigated PLA specimens were manufactured with different porosities and thicknesses.

It was found that the sound reflection properties of the studied PLA specimens were influenced, not only by the type of 3D-printed structure, but also by the volume porosity and thickness of the material samples and the air gap size behind the investigated PLA specimens inside the acoustic impedance tube. It can be concluded that the PLA samples manufactured with the starlit structure exhibited lower sound reflection compared to the other investigated PLA structures, especially for specimens with a thickness of 10 mm. This was because the starlit structure is created by more complex pore shapes, resulting in multiple reflections during the propagation of soundwaves through this structure and thus greater conversion of sound energy into heat. It can also be stated that a higher ability to reflect sound from the tested 3D-printed open-porous PLA materials was generally observed at low excitation frequencies and for thin, highly porous samples without the air gap size inside the impedance tube. At higher excitation frequencies, it was possible to place the porous lightweight sample at a suitable distance from the solid wall to improve the sound reflectivity while reducing its weight compared to hard, unperforated solids, which are generally characterized by good sound reflection properties. For this reason, it is possible, for these purposes, to save time, production costs and energy, which is one of the current worldwide trends.

 

[tnsilver]

if I did a double blind test I highly doubt anyone could detect a difference in sound with any better odds than guessing

So I'm not the only one speculating... It would be nice if you actually do it. The paper, BTW, is about sound propagation through PLA in the context of construction and architecture. I'm not sure it applies to headshells. We're not talking SPL in a headshell - it's the damping properties of the material that are of interest to us.

I definitely don't think the Thorens mojo was fairy dust sprinkled on the factory production floors. My bet is on the drawing boards. These could have been in Berlin for all I know. They've never designed anything w/o reason and they were pretty cost effective too. There's reason other than the obvious for the TP-60 to be made of magnesium alloy. Maybe PLA can sub for it. Maybe not...

 

[Timothy Flath]

So I'm not the only one speculating... It would be nice if you actually do it. The paper, BTW, is about sound propagation through PLA in the context of construction and architecture. I'm not sure it applies to headshells. We're not talking SPL in a headshell - it's the damping properties of the material that are of interest to us.

I definitely don't think the Thorens mojo was fairy dust sprinkled on the factory production floors. My bet is on the drawing boards. These could have been in Berlin for all I know. They've never designed anything w/o reason and they were pretty cost effective too. There's reason other than the obvious for the TP-60 to be made of magnesium alloy. Maybe PLA can sub for it. Maybe not...

Switzerland more likely since that is where the parent company was at the time the headshell was developed. Manufacturing and R&D according to the history books ported over to the village of Kuhbach around 1966 (many say Lahr but that is actually incorrect - Lahr was merely the nearest small city). https://www.theanalogdept.com/thorens_history.htm

I am quite clearly not the one that needs to be convinced though since I use these headshells interchangeably with the real ones (I have 7 TP-60's at least) daily with nary a thought or no ill effects. Sounds like you are the one that needs to "do it" and be conviced. I wonder how much R&D Schopper (https://www.schopper.ch/index.php?page=headshell-tp60) and Audiosilente (https://www.pinterest.ca/pin/796152040347102476/) actually put into theirs?

Bottom Line Up Front (BLUF), I don't really care whether anyone actually believes me or not since I really gain nothing from it other than my desire to (freely) share a more reasonably priced and effective alternative (among other Thorens related things) to a headshell that is getting harder and harder (and more expensive) to to find these days. Incidentally 3D printing is not limited to a PLA rabbit hole as far as being the only material out there so you maybe somewhat missing the point. Depending on your budget, specific printer and wherewithall there are numerous materials you can choose from if you have my design and the propensity for such fetishes. You would have to prove to me (and not the other way around) what specific engineering went into the original headshells back in 1972. I doubt anyone can now (other than mere speculation as you seem to be so fond of despite vehemently denying it...). Thorens changed headshell designs and materials like they changed underwear over the years like many other TT manufacturers did I'm assuming. If the Magnesium alloy is so great from a materials engineering perspective why did they not just stop there with the perfect engineering solution? I do know first hand that the Magnesium alloy corrodes quite badly (especially here on Vancouver Island with its maritime climate surrounded by ocean). If you want to see some photos of nasty corrosion on several TP60 headshells I can easily provide. Over to you...

https://www.thingiverse.com/navydiver/designs

 

[tnsilver]

Right... the 22° offset angle, the 10g weight to sum up to 16.5g effective mass of the TP-16, the magnesium slide, the lock pin... It's all an accident.

You know, ever since the TD-150 with the TP-50 headshell in the late 60's, until the bankruptcy, Thorens had the TP-60 headshell and the TP-62 and TP-63 wands. From 1972 to the end of the 80's they used just those three on all TD-12X/14X/16X variants. I'm pretty sure their personal hygiene was a little better than that, and that they've changed underwear a little more often. It doesn't look like you know that much about Thorens as you might think.

I've just raised a concern. You've totally failed to reassure me by getting defensive. There must be a reason for that. As much as I like it, now, more than ever, I don't trust that replica.

 

[Timothy Flath]

Part 6 is now a wrap and we are getting much closer to completion. Most of the hard parts are done now which is the good news. This particular video covers: Tonearm Bearing Verification, Tonearm Setup and a Plinth Change. There are still some more interesting videos yet to come. First and foremost we are ready for a good sound check coming next video post. I am also planning to do a cartridge change to a Goldring E3 mounted on one of my other 3D printed headshells (I have one E3 mounted on a 3d headshell already but it is on a theme table with a coloured 3D headshell which will not match this table. Will move it to a black one to match a standard TP-60 headshell. Remember also that I can always interchange any of my four Thorens turntable's carts/headshells (2 X TD-160 and 2 X modded TD-165) amongst each other with only a little rebalancing required since the effective arm length are all the same. Also coming up is a DIY dust cover I will be building for this table with an acrylic bending machine I built quite some time ago. All kinds of fun yet to come and topic requests are always welcome:

 

[JohnT123]

Tim, thank you for the hard work putting this series together. Even though my Thorens is not like yours, there's still lots of stuff that crosses over between the models.

Mine has the hideous TP11 MKII arm and the headshell that looks like a space ship. I hate it, but love the overall sound and performance of the table. In addition to the headshell/arm issues mine is starting to have motor knock on occasion. Your tutorial on dealing with that has been very timely.

 

[Timothy Flath]

Right... the 22° offset angle, the 10g weight to sum up to 16.5g effective mass of the TP-16, the magnesium slide, the lock pin... It's all an accident.

You know, ever since the TD-150 with the TP-50 headshell in the late 60's, until the bankruptcy, Thorens had the TP-60 headshell and the TP-62 and TP-63 wands. From 1972 to the end of the 80's they used just those three on all TD-12X/14X/16X variants. I'm pretty sure their personal hygiene was a little better than that, and that they've changed underwear a little more often. It doesn't look like you know that much about Thorens as you might think.

I've just raised a concern. You've totally failed to reassure me by getting defensive. There must be a reason for that. As much as I like it, now, more than ever, I don't trust that replica.

Not defensive, just factual and absolutely not an expert (thought I made that clear at the start of this video series). Suit yourself though, you certainly do have choices. I cannot change peoples minds unless they are willing to try it for themselves especially when the cost is quite minimal...

Anyway, loved my old TD-150 MK II. Gave it to a very good buddy on his retirement (worked closely with me on the military base here in the Engineering unit on the Naval base). He also worked in an audio shop an hour up the road from Lahr at CFB Baden Soellingen, West Germany where I also went to High School for 4 years prior to living in Lahr (post college). He was the Nakamichi rep back then. We are in the same same close audio group here in town. Here is that wonderful table (complete with squeaky chair) that I set up (similar to this one) playing on a tube amp I built (yes original headshell):

 

[Timothy Flath]

Tim, thank you for the hard work putting this series together. Even though my Thorens is not like yours, there's still lots of stuff that crosses over between the models.

Mine has the hideous TP11 MKII arm and the headshell that looks like a space ship. I hate it, but love the overall sound and performance of the table. In addition to the headshell/arm issues mine is starting to have motor knock on occasion. Your tutorial on dealing with that has been very timely.

Much appreciated, Thank you

Have you tried a thrust bearing yet or is the motor shaft bent?

 

[Timothy Flath]

Part 7 - The first sound check. A lot of nasty smart phone mic artifacts near the beginning so the sound here does not even come close to how it sounds live in person sorry to say but it does get a bit better in the musical passages towards the end if listening to a decent media system rather than phone speakers - I certainly need a better camera and mic system...

 

[JohnT123]

There's been no impact on the shaft so I assume it's a worn bearing. It's not knocking at all times. It sometimes starts when I use a cleaning brush and then it goes away. I assume it will only continue to get worse over time.