Thorens TP13 correct alignment

[Alfmonster]

I recently reinstalled the TP13 tonearm (the one without the anti skate) with the Shure v15iii cart/Jico SAS stylus and have been incredibly surprised at how good it sounded. Is this an underrated tonearm? I had an SME 3009 on here which also sounded great but the TP13 seems to be pretty darn good also.

Currently I have the alignment set to Baerwald but I vaguely remember someone saying that Thorens recommended Stevenson?

I’m a bit confused as to what the correct alignment for the TP13 seems to be. And despite my searches on various forums I can’t seem to find what Thorens recommended.

I couldn’t find anything definitive on this- however any help would be greatly appreciated. Thank you!

 

[JohnT123]

The only Thorens protractor I've ever seen is the Baerwald.

 

[Alfmonster]

The only Thorens protractor I've ever seen is the Baerwald.

yeah me too - just started second guessing it bc I hadn’t calibrated this arm in a while and I vaguely remembered someone on one of these forums telling me that Stevenson was the original arc for the Thorens td150 Mki / TP13.

The confirmation helps a great deal. Thank you

 

[muchachos]

From what I understand, the alignment curves are calculated given a specified set of inner and outer groove dimensions, and as such are not absolute. It's a bit more complicated than just comparing the prescribed null points - which are not always provided by Thorens, as they seem to be unavailable for the TP13 arm. It measures 215 mm however just as the TP16 and TP 11 do, however their overhang is specified at 18mm in the manual rather than the 14.4mm specified for the TP16 family. This would be closer to a Loefgren alignment if I'm not wrong, as opposed to the Stevenson-ish alignment they used with the TP16 with a null point right outside the centre label.

As for the underrated comment - potentially? I had a TP13a which seemed flimsy and worn, so I decided to swap it out. I suspect many of these don't wear well, so surviving examples in nice shape will pleasantly surprise users. The ball bearing pivot design and underslung counterweight reminds me of the AR tonearm, which has its share of devotees as well.

 

[Alfmonster]

From what I understand, the alignment curves are calculated given a specified set of inner and outer groove dimensions, and as such are not absolute. It's a bit more complicated than just comparing the prescribed null points - which are not always provided by Thorens, as they seem to be unavailable for the TP13 arm. It measures 215 mm however just as the TP16 and TP 11 do, however their overhang is specified at 18mm in the manual rather than the 14.4mm specified for the TP16 family. This would be closer to a Loefgren alignment if I'm not wrong, as opposed to the Stevenson-ish alignment they used with the TP16 with a null point right outside the centre label.

As for the underrated comment - potentially? I had a TP13a which seemed flimsy and worn, so I decided to swap it out. I suspect many of these don't wear well, so surviving examples in nice shape will pleasantly surprise users. The ball bearing pivot design and underslung counterweight reminds me of the AR tonearm, which has its share of devotees as well.

this is incredible information - thank you! Yeah I couldn’t find anything on the proper arc as well. So you’re saying that the TP16/11 would be baerwald but you believe the TP13 is probably Loefgren bc of the 18mm overhang?

 

[muchachos]

this is incredible information - thank you! Yeah I couldn’t find anything on the proper arc as well. So you’re saying that the TP16/11 would be baerwald but you believe the TP13 is probably Loefgren bc of the 18mm overhang?

Digging out some of the protractors I've used over the years for my Thorens.... If you dink around with Conrad Hoffman's Template Generator for long enough, you can figure out a lot. The 18mm overhang however is characteristic of a Lofgren alignment, whereas Stevenson tends to be much closer in.

Using the TemplateGen tool I can get an 18.06mm overhang given a 215.6mm spindle to pivot distance, which provides for inner radius at 69.7mm and outer at 116.37mm. Thorens must've used something quite close to that, which is basically the Loefgren alignment. Offset is 23.46 degrees.

Meanwhile, the TP11/16 is closer to a Stevenson - it uses 14.4mm overhang, 22 deg offset angle, and null points of 54.5mm and 117.8mm, based on a pretty close-in inner groove cut which was used by DIN as a standard. I've used it as well with a Baerwald alignment with null points at 63.1 and 119.2mm, giving me an overhang of 16.8mm and 23 deg offset angle. This is pushing the cart almost to the edge of the headshell however. I think this alignment worked better with that arm than the standard, but not markedly so. Most of my LPs are not cut to a 55mm radius either.

 

[Alfmonster]

Digging out some of the protractors I've used over the years for my Thorens.... If you dink around with Conrad Hoffman's Template Generator for long enough, you can figure out a lot. The 18mm overhang however is characteristic of a Lofgren alignment, whereas Stevenson tends to be much closer in.

Using the TemplateGen tool I can get an 18.06mm overhang given a 215.6mm spindle to pivot distance, which provides for inner radius at 69.7mm and outer at 116.37mm. Thorens must've used something quite close to that, which is basically the Loefgren alignment. Offset is 23.46 degrees.

Meanwhile, the TP11/16 is closer to a Stevenson - it uses 14.4mm overhang, 22 deg offset angle, and null points of 54.5mm and 117.8mm, based on a pretty close-in inner groove cut which was used by DIN as a standard. I've used it as well with a Baerwald alignment with null points at 63.1 and 119.2mm, giving me an overhang of 16.8mm and 23 deg offset angle. This is pushing the cart almost to the edge of the headshell however. I think this alignment worked better with that arm than the standard, but not markedly so. Most of my LPs are not cut to a 55mm radius either.

gosh so I’ve been tinkering with this for the morning - and have realized that maybe for the Thorens TP13 you may not need the Feickert protractor…
From my understand, it seems you set the VTA according to the manufacturer (15 degrees for the v15iii), then adjust the overhang using the 45 adaptor. At that point, I think you might be done as this is basically what the DF protractor does?

 

[ConradH]

It's a bit of a stretch to think that an arm can be designed for a given alignment. There's basically one design decision- where to put the pivot point in relation to the platter spindle. After that it's just a matter of making the arm long enough to reach the cartridge and giving the headshell slots that allow aligning the cartridge to whatever strategy is thought to be best. If you measure your pivot to spindle distance and enter it into my template generator, everything else will be revealed for standard alignments. If the calculated overhang agrees with the manufacturer, great. Otherwise, ignore the manufacturer's number because you probably don't know how they arrived at it. Another very useful tool is John Elison's spreadsheet. That will let you explore the results of any alignment in detail. Remember, the Lofgren & Stevenson strategies are just points on a continuum. There are an infinite number of choices that can be considered correct, depending on priorities. The math in my generator produces those standard alignments, but if you're willing to iterate the groove limits and other numbers, it will produce a "correct" arc template for whatever alignment you can conceive of. IMO, still best to stick with the standards.

Scroll down for John Elison's Excel spreadsheet- https://www.enjoythemusic.com/freestuff.htm

My infamous template generator, third item down- http://www.conradhoffman.com/chsw.htm

CH

 

[tnsilver]

My infamous template generator, third item down- http://www.conradhoffman.com/chsw.htm

Your "infamous" template generator is actually ingenious. It's the only thing that makes me keep an old Windows 7 OS on some old laptop. I was thinking of converting it to Java and making it multi-platform so it can run seamlessly on macs and linux and become "famous". I'll keep that thought for the day I retire.

 

[Alfmonster]

It's a bit of a stretch to think that an arm can be designed for a given alignment. There's basically one design decision- where to put the pivot point in relation to the platter spindle. After that it's just a matter of making the arm long enough to reach the cartridge and giving the headshell slots that allow aligning the cartridge to whatever strategy is thought to be best. If you measure your pivot to spindle distance and enter it into my template generator, everything else will be revealed for standard alignments. If the calculated overhang agrees with the manufacturer, great. Otherwise, ignore the manufacturer's number because you probably don't know how they arrived at it. Another very useful tool is John Elison's spreadsheet. That will let you explore the results of any alignment in detail. Remember, the Lofgren & Stevenson strategies are just points on a continuum. There are an infinite number of choices that can be considered correct, depending on priorities. The math in my generator produces those standard alignments, but if you're willing to iterate the groove limits and other numbers, it will produce a "correct" arc template for whatever alignment you can conceive of. IMO, still best to stick with the standards.

Scroll down for John Elison's Excel spreadsheet- https://www.enjoythemusic.com/freestuff.htm

My infamous template generator, third item down- http://www.conradhoffman.com/chsw.htm

CH

thank you so much for this!! I am unfortunately running a mac (@tnsilver please let me know when you make this cross platform). I may have to get something a virtual machine program to let me run Windows to use this.

 

[ConradH]

I don't know beans about Macs, but apparently there's something called Wine and another one that will allow you to run the program.

 

[tnsilver]

There's about 6 good windows emulators and VM's for mac, with Wine, CrossOver, Virtual Box and VMWare Fusion to name a few and there's parallel versions for linux, but... Lemme just tell you how we feel about those emulators. My grandpa died from colon cancel in the late 70's. Back then it was an entirely different thing and diagnosis came late - too late. At 66 he was dying on a hospital bed, lucid and physically able except he had a plastic sack attached to the side of his stomach to collect the digestive waste that his body could not process any longer. That bag, the tubing, the dressing around it, emptying it, the sterilization each time, it all required a dedicated nurse to attend him 5 times a day. He couldn't mobilize, or even sit up, because of that plastic sack attached to him. A VM on a linux distro, just so that it can run MS executables, is like that plastic sack. It requires too many resources, it's disabling the main system, and it's full of crap.

 

[EWarrior]

There's about 6 good windows emulators and VM's for mac, with Wine, CrossOver, Virtual Box and VMWare Fusion to name a few and there's parallel versions for linux, but... Lemme just tell you how we feel about those emulators. My grandpa died from colon cancel in the late 70's. Back then it was an entirely different thing and diagnosis came late - too late. At 66 he was dying on a hospital bed, lucid and physically able except he had a plastic sack attached to the side of his stomach to collect the digestive waste that his body could not process any longer. That bag, the tubing, the dressing around it, emptying it, the sterilization each time, it all required a dedicated nurse to attend him 5 times a day. He couldn't mobilize, or even sit up, because of that plastic sack attached to him. A VM on a linux distro, just so that it can run MS executables, is like that plastic sack. It requires too many resources, it's disabling the main system, and it's full of crap.

Actually Wine is an acronym for "Wine is not an emulator"

I believe it doesn't even run on current version of Mac OS. I had to dig out an old MacBook from the mid-2000s to use it. And then the print results were less than ideal for me, which was probably a driver issue.
This lead me to develop a web based arc protractor generator last year: https://alignmentprotractor.com/arc-protractor-generator

 

[ConradH]

Ford is "found on road dead" or "fix or repair daily" but it still (usually) gets you where you want to go. (also "first on race day") Anyway, good job on the online version. Something people should be aware of- non-arc templates (I've never liked protractor, even though it's correct) need two grids. An arc template doesn't, and you'll get correct alignment off either grid alone. Only worry if there's disagreement between them, as it means the arc wasn't followed correctly or something moved.

 

[tnsilver]

good job on the online version

 

[EWarrior]

Ford is "found on road dead" or "fix or repair daily" but it still (usually) gets you where you want to go. (also "first on race day") Anyway, good job on the online version.

Thank you And thank you for the arc template generator. Without yours, mine wouldn't even exist. I would never have gotten the idea of programming anything if it wasn't for your application.

Something people should be aware of- non-arc templates (I've never liked protractor, even though it's correct) need two grids.

One grid and a sighltline at the linear offset distance (to be pointed towards the tonearm pivot point) will also do. Might be a project for my next vacation

 

[ConradH]

I've always been wary of using the sightline method because, depending on the clutter in the pivot area, it isn't very precise. OTOH, you should examine the technique and see how much one can get away with. It might be good enough even if you miss by a small amount. Bad case of OCD here, so I'm not the one to judge.

 

[EWarrior]

I've always been wary of using the sightline method because, depending on the clutter in the pivot area, it isn't very precise. OTOH, you should examine the technique and see how much one can get away with. It might be good enough even if you miss by a small amount. Bad case of OCD here, so I'm not the one to judge.

I totally get your OCD and wouldn't use anything but arc protractors myself, but I think the three types of protractors all have their strengths and weaknesses:

2 point: universal, precise, difficult to use
arc: designed for one particular pivot to spindle distance, precise, easy to use
sightline: universal, imprecise, easy to use.

I guess some people will find them useful...

 

[tothmes]

The TP13 and TP14 are actually shockingly good arms, when properly renovated and used with well matched cartridges. Since they are short (8") conicals are better suited, but ellipticals work fine too. Preferably low compliance, due to the high mass of the arm.

I think most of these arms have had a badly aged back end rubber grommet for the last 20 years or so, which in obvious cases make the counterweight sag. But long before that the rubber has lost its intended properties, which ruins the resonance damping (and frequency) of the arm. You can't make these arms sound as they should without replacing that grommet, preferably with one with the proper shape and stiffness. As far as I know, you can only get replacement parts from Schopper, or from me. Full disclosure: I do make and sell new copies of these grommets. I cast them i a polyurethane that I've found ideal. I haven't yet come across the EMT versions of these arms, but from the photos I've seen I think those have PU grommets too. The EMTs are semi transparent, I make mine in black. And no, the TP13 and 14 are of course not the same thing as the EMTs.

Apart from replacing the grommet, all the normal procedures apply. Since you must take the arm apart in order to replace the grommet, you can just as well do the full monty: clean and polish the bearings (no oil!), clean up and oil the other moving parts, adjust the scale for the VTF, and replace the internal wiring. (Not because of voodoo, but because the old ones have a dried out and stiff isolation, and you want to reflow the solders anyhow).

With that done, what you have is a high mass arm capable of fantastic dynamics, sounding far better than one would expect by the simple looks. Of course, there are better ones to buy if you can afford them, but I always recommend folks to give these arms a fair chance before tossing them out.

Edit:

...sorry - the grommet part of this of course applies to the TP 14. The TP13 is also much better than most realise, but it doesn't have the rubber grommet of the TP14!

 

[pockets64]

where did the pivot to spindle distance measurement come from , am having difficuly finding specs for the tp13 arm and on rough measuring it seems to be around 212mm but obviously i'm out if thats the official dimensions .