What is you tonearm’s Maximum Distortion?

I like chocolate. I know cocoa beans.

Time for us to lobby the cartridge/stylus industry for zenith error specs!

@optimize , Like anything in life there is a range of tolerance usually decreased by monetary issues. A cartridge manufacturer orders so many of one particular cantilever-stylus assembly. Within that order there is a range of accuracy. The manufacturer selects the best units for his expensive units and religates the not so hot ones to lesser models. Perhaps the real bad ones are returned for credit. All the poorly mounted styluses I have observed have been on cartridges under $1000.00. I have three $10,000.00 plus cartridges and all are perfect. I also have a $3000.00 Soundsmith cartridge that is perfect.

Zenith error is a more critical issue for fine line contact styluses. If the error is enough for me to see it under low power I would return the cartridge as defective. Twisting the cartridge to correct the error now puts the coils out of alignment. Bending the cantilever is out of the question, try it if you do not believe me.

Most people do not look at their cartridges under good magnification. Good magnification is expensive. If you are an audiophile spending over $500 on a cartridge it is a good idea to have the stylus alignment examined by someone who knows what they are looking at like J.R. above. Do it early while the cartridge is brand new and under warranty. Do not assume because your cartridge comes from a reputable company that it is OK. The absolute worse cartridge I ever examined was from Audio Technica. Nobodies QC is perfect. 

Zenith error should be able to be resolved with a compensatory alignment angle I assume. Ears seem an adequate way to hone it in, once an appropriate alignment protractor is chosen and set to (although time consuming).

Thanks @wallytools ! You guys are doing a great job.

Yes, there is most likely bigger fishes to fry than select a alignment but we need one anyway so why not select one of the better ones.

But it is something that we can do easily. And by understanding what they’re bringing to the table makes it simpler to choose the correct one when knowing their strengths and weaknesses from our priorities.

 

The zenith error is baffling that the 3 different mounting companies that mount the diamond to the cantaliver is having that low precision!

Here we go and have different inventions of stylus diamond advance shapes that has very small cutting to make those shapes and ridges.

It feels that we have a made a very beautiful and precise part the diamond and then we have a cantaliver that is tapered aluminum, boron or other highly refined material.

Then we take those two parts and ask someone that has not the understanding of their beauty and precision made parts and their importance of their alignment when gluing them together as a whole unit. I mean it feels that it is not done with the proper care and attention that those parts deserve or with the same precision as they were crafted.

Keep up the good work and hopefully cartridge manufacturers start to put higher requirements on those manufacturers because their tolerances you have uncovered to the public is not doing their products and efforts any favors.💞

 

 

Btw, this is the scenario of SAT:

 

Tonearm Alignment Calculator Pro - Vinyl Engine

 

R.

@intactaudio : " manipulated numbers without disclosing the manipulation to justify someones choice."

" your proposed alignment simply "

 

and way before you posted the graphics I posted to you:

 

 

" that is the SAT tonearms alignment. "

Btw, was ridiculous/false/untrue/lie that in your graphic instead to write SAT use it my name when the alignment came from SAT and I posted to you before that graphic and you knowed.

 

" I do not believe he would fudge the inner groove radius to 75mm in the calculations "

 

that’s only your ignorance because you showed with this kind of statements that your knowledge level on the SAT tonearm is near zero. Your problem not mine.

 

""" Everyone is allowed their own choice of compromise """

 

Yes, that’s why exist the custom key in the calculators.

 

@optimize thank’s for your expert explanation.

 

Btw, intactaudio you posted that with the SAT the distortion level goes at 60mm to 2%. Well could be that your speakers goes even way higher that that figure and no compliant about. The phono stage you are using ( I think you are using it ) develops a huge distortion level with that high swing of 3db deviation in the RIAA inverse eq. and I can understand with out compliant because it’s what you are using and that makes more harm that the SAT alignment. Incredible that you made a " film of drama " on this issue.

 

In the other side all SAT owners are fully satisfied with Mark tonearms. I listen 3 times to the SAT and it’s really good and I think that @mijostyn did it and like it too.

 

I think that if your main undisclosed attitude is to hit me then you are wrong in that specific alignment issues that as I told you I’m only using it and whith not the kind of critics like you other than exactly the same opinion that @optimize about Stevenson A alignment.

 

So I appreciated if you take off my name in your posted graphics due that no belongs to it.

 

R.

 

 

Hi guys,

Debates on this level of refinement (which alignment pattern to use or which tonearm offers lowest tracing distortions) are really insignificant compared to zenith error tolerances in the cartridge industry. Your zenith error should be known and corrected before any of this inquiry will deliver results. The average zenith error in the last few hundred cartridges I’ve analyzed is a hair over 2.5 degrees. If we look at the dataset with Gyger replikants removed, that number goes up substantially. Industry assembly tolerances are so far beyond the differences between Loefgren, Baerwald, Stevenson, etc that the debate and inquiry offers limited “yield” until zenith correction is satisfied.

I don’t mean to rain on you fellows. There still may be value in this inquiry but it can’t benefit us until we’ve first managed the elephant in the room.

I am still in development with a tool to correct for zenith error in the field so it does not require sending to me in the lab. Technically, the WallyZenith allows for it already but the correction involves using your ears in a rather tedious process of listening for best results. The tool makes it very easy to know where you are and return to any previous position with a high level of accuracy.

You might ask why I bothered to put alignment variations in the WallyTractor in the first place then. Simply: I redesigned the WallyTractor before I came to realize how poorly stylus/cantilever assemblies are made and mounted.

In a product development process I had to do repeated static and dynamic repeatability tests for zenith error in which I repeatedly aligned the cantilever by 0.5° increments. We were able to confirm that these attempts were accurate though I do believe 0.5° is likely my limit of resolution when aligning a cantilever. One of the engineers on our research team who has a fantastic analog rig and is a VERY discerning headphone listener insists he can hear 0.5° zenith error differences on his pivoted tangential tracking arm. I have not blind tested him on this but I’d say that I’m not worried about resolving below 0.5° accuracy based upon what I’ve seen in Matlab and Abaqus with respect to fine changes in zenith error.

The tracing error difference between Loefgren and Baerwald is less than that. So is the difference in tracing error between a 9” arm and a 12” arm.

As we see here in the graph below 👇

The Löfgren B has lower distortion all over the record surface except in the end just before lead-out starting. But we also know that a 12" LP always start at the same diameter but the 60 mm at the lead-out is something that they recommend that we stop to cut information closer to the label than those 60mm. The issue and problem is to:

1. Find appropriate track to put as the last one. On that A/B side. When the resolution is lowest there.

2. Because of the above we would like to make so that side A and B ends at the same radius. In other words it is not wise to end one side at ~80/90 mm and the other side at 60mm. If we could rearrange the track order so both of the sides end at 70 mm instead. For better fidelity.

3. Many 12" 45 rpm ends further out than 60mm and has a big area lead-out.

4. Do we push the envelope to go closer to the label than 60mm then we get issues with some auto stop or automatic return mechanisms in automatic TT.

So in short lead-in is more or less always at the same place but the same can not been said regarding lead-out, it is far from all 12" discs that end at 60mm when many ends future out for some of the reasons above. With that insight it is less of importance to optimize at just 60mm like Stevenson do in the graph below.

 

It seams that the consequences and penalty for having that aim is that having the lowest distortion from 60 to 65mm (were Löfgren B crossing Stevenson) is that Stevenson has higher distortion then Löfgren B from 65 mm and more or less the whole way until the start and lead-in of the disc!

That is a high price to pay and is only benefits if you has overture 1812 with canons at the end between 60 to 65mm or bolero and other crescendos in that area in many of your favorite albums may have.

 

Otherwise Stevenson is in my opinion something nobody should use. And maybe there is a reason why Lofgren calculated and created a second and improved version after his first attempt.

 

 

Here we see that this record side is actually close to 60mm:

And as you see it is those 5mm I "sacrifice" with my Löfgren B:

 

So it is not a huge "sacrifice" if now the lead-out starting at 60mm.

Or in other words someone that prefer those 5 mm to have the LOWEST distortion on the record has actually "sacrificed" and choose a higher distortion from those 65mm and the whole way to the start of track one!

While I do hear some inner groove distortion sometimes, I am grateful to the last track for giving me a bit more listening time per side.

@rauliruegas 

Well, don’t tell to me but directly to the SAT designer.

I do not have an issue where mark sets his null points and I do not believe he would fudge the inner groove radius to 75mm in the calculations to avoid showing the sharp increase in distortion once you get closer than 75mm.

 The OP P2S 225.. was asking for better numbers and the SAT ones gaves it.

Sure... if you use a little harmless parameter manipulation and substantially shift away from a standard set of inner/outer groove numbers you can get vanishingly low numbers.  

" I have found no point in listening to the last track ... "" that's at least untrue because the higher distortion happens only with the LP that has groove modulations  up tp 60mm ( inner groove )

This is akin to saying that a silent groove has no distortion.   JR @wallytools makes a compelling argument and has collected data to support a trend in newer records and audiophile reissues to basically leaving the last track off each side to avoid the issues with the inner groove.  He offers a protractor with dual alignments to take this into account and makes it very clear what his goal is.  The key here is he gives all of the information and lets the end user select what best fits their listening style.  Taken to the extreme I could even see a second arm being added to a setup to allow for two different alignments to match JR's observations.

Btw, have you an alignment with no trade-offs?

Nobody does.  I actually believe that there are far too many variables that cannot be set accurately enough to get any specific alignment and simply getting two null points on the playable surface is no small task.  I want to be clear that I am not being critical of anyones alignment goal.  Everyone is allowed their own choice of compromise.  My problem is presenting manipulated numbers without disclosing the manipulation to justify someones choice.

 

dave

 

 

@intactaudio : " If the parameter manipulation is kept hidden then there is another term for it.. "

Well, don’t tell to me but directly to the SAT designer. The OP P2S 225.. was asking for better numbers and the SAT ones gaves it.

" I have found no point in listening to the last track ... "" that's at least untrue because the higher distortion happens only with the LP that has groove modulations  up tp 60mm ( inner groove ) and even that you don't know if could be aware of it due that distortion goes in increment or decreasing groove to groove and ears goes accustom to. Not easy todetct it. Don try to " satanize " it: bad attitude.

 

Btw, have you an alignment with no trade-offs? and if you don’t have it then maybe it’s the rigth time that you do it because you critic and critic but don’t give nothing in change. Yes, you are free to post whatever you want but could be bette to leaft to critic the standard alignments and show a no trade of alignment that we all can name intactaudio. Show something and stop critic because that critics goes not against me because I did not any alignment I only use it as all audiophiles.

 

Which tonearm/cartridge alignment are you using?

 

R.

@lewm 

I am skeptical in using the calculated number for anything other than crude relative comparisons and find the plots to be much more telling of the relationships at hand. Below are the plots for the table @optimize posted above.  From looking at the table the Löf B sure looks appealing but the plots tell a different story if you are at all concerned about the last track on an original Blue Note.

 

for reference, here are the plots of the "low distortion parameter manipulated" alignment @rauliruegas posted.   When using a similar alignment I have found no point in listening to the last track or two of a side.

 

I have found that that the traditional 2X weighting factor is not representative of what I hear and that the weighting should be more like 4X. It seems you really need to cheat things to the inner groove closer to Stevenson to get a full side of high quality reproduction.  The last little tidbit is in general the numbers from these charts need to be multiplied by a factor of 5-10 to actually be representative of a real world measurement.

dave

If the numbers in the table published here by optimize are correct, two things pop out at me. First, the distortion figures are below 0.5% or equal to 0.5% in all cases. Given all the other distortions inherent to vinyl reproduction, does anyone here think he can hear the difference between 0.5% and 0.3% distortion? second, there is a dissociation between the magnitude of the tracking angle, error, or at least the maximum magnitude of the tracking angle error and distortion. Isn’t that interesting?

@rauliruegas 

It’s only a parameter manipulation

Only a parameter manipulation??? If the parameter manipulation is kept hidden then there is another term for it.

dave

 

 

@intactaudio : It’s only a parameter manipulation and that is the SAT tonearms alignment. At the end is not rocket science. Btw, Did you already test that kind of alignment?, I do and you can be " surprised " by. 

As Mark SAT designer says and makes sense:  " The null points for the SAT arms are located at 80 and 126mm. Ultimately, this was a choice of enjoying a consistently higher level of fidelity for 95% of the time over having less angular error on 5% of the tracks. "

Exist rules but to each one of us can be broken in favor of quality performance with MUSIC.

That alignmnet by SAT is wrong? no it’s only different and when tested each one of us can decide about. What you think or what I think is only that " think " as is non-important in the whole alignment game: it’s each one game not yours not mine.

 

R.

Parameter	Custom	Lofgren A	Lofgren B	Stevenson
pivot to spindle (mm)	216.5	215.96	215.45	218.02
effective length (mm)	233.7	233.7	233.7	233.7
overhang (mm)	17.2	17.74	18.25	15.68
offset angle °	22.95	23.57	23.57	22.35
linear offset (mm)	91.14	93.44	93.44	88.87
inner groove (mm)	60.33	60.33	60.33	60.33
outer groove (mm)	146.05	146.05	146.05	146.05
inner null point (mm)	67.42	66	70.29	60.33
outer null point (mm)	114.86	120.89	116.6	117.42
maximum error °	2.25	1.85	2.06	2.24
maximum distortion %	0.77	0.64	1.03	0.77
average rms distortion %	0.38	0.42	0.37	0.5

 

Thanks @intactaudio !

Here is my numbers seams they are pretty good compared to the other's. Using the Löfgren B that is the best on the average for a whole LP. 

I did my custom protractor several years ago and it seems to be OK and the numbers I took from that custom protractor.

So I did this also to check its old calculations. 👍🥳 

@optimize   in order to enter your desired overhang and offset you need to tick the "custom" option or the program will calculate for the 'standard' alignment ticked.

Also the number you enter into the initial arm length will autofill to the remaining three so make sure the same P2S / EL dot is ticked for all 4.  

For your calculation enter 233.7 in Arm 1 Arm Length and tick the effective length dot for all 4 arms.  Then Click the Arm 1 custom dot and enter your desired overhang and offset angles and the results will compare 'your alignment' to the big three.

dave

I do not get the calculator to work.

I enter in effective length 233.7, overhang 17.2 and offset angle 22.953° with Löfgren B.

And in the calculations and table it spits out today different offset angle  and overhang than I have entered.

I think that the calculator is totally worthless when it spits out data that is not my offset angle  and overhang. (And it doesn't calculate with the provided indata)

So those that got some output did you look that the indata were used is intact or were there their own made up values from the calculator itself!

Or am I missing something here?

@rauliruegas 

Since we are considering the theoretical, your proposed alignment simply looks like Löfgren A if you cheat the inner groove radius to 75mm and the outer groove to 143mm which is not realistic for all but the smallest selection of music.  Distortion at the 60.325mm inner groove point will be a fair bit over 2%

dave

@intactaudio  : Yes.

 

R.

Thanks to those who posted their figures. It is much appreciated.

@rauliruegas 

Forgot that if you want lower distotion figures then and using Löfgren A alignments its tonearm parameters set up are:overhang  21.58mm and offset angle  24.8°.

Where the maximum error  0.94°   maximum distortion  0.33%  and average distortion  0.22%.  All these for your P2S  225mm.

 You need two additional parameters to make the tonearm/cartridge set up and achieve those figures of lower distortion levels and that I don't gave you and are the null points that are: 80mm. and 126mm. not the one you are using today.

are the three quoted sets of numbers referring to the same setup?  

Like Lew, I am skeptical of the accuracy of the 'calculated' distortion numbers since the whole description is to vague. @nrenter  posted a screen grab to John Ellison's Excel spreadsheet.  which can be found on the Enjoy the Music site. This file has the description below of what the calculated percentage distortion refers to.

   Tracking Distortion (Column D) is based on dividing tracking error by groove radius; this is also called weighted tracking error.  Be advised that these numbers are scaled   so that they represent actual percent tracking distortion at a stylus tip velocity of 10 cm/sec.  In other words, the number 1.0 in Column D represents 1-percent distortion.

dave

This spreadsheet…
 

 

Dear @fusian  : You need two additional parameters to make the tonearm/cartridge set up and achieve those figures of lower distortion levels and that I don't gave you and are the null points that are: 80mm. and 126mm. not the one you are using today.

R.

Using a protractor like the Wally unit or the SmarTractor you can adjust almost any set up to a number of alignments by playing with overhang and offset so that the cantilever is tangent at the two null points. 

Greetings 

Per VinylEngine’s calculator my arm reads as follows:

Max. Tracking Angle Error: 1.86 degrees 

Max. Distortion: 0.64 percent 

Avg. RMS Distortion: 0.41 percent

Joe Nies

Thanks petg60 and Raul, much appreciated.

@fusian  : Forgot that if you want lower distotion figures then and using Löfgren A alignments its tonearm parameters set up are:overhang  21.58mm and offset angle  24.8°.

Where the maximum error  0.94°   maximum distortion  0.33%  and average distortion  0.22%.  All these for your P2S  225mm.

Please don't ask how I found out those numbers because I have no time to explain you ( using VE calculator. ) or to any other gentleman, but that's it.

 

R.

 

 

Dear @fusian  : Around 90% of tonearm manufacturers used and use one of the 3 best knowed alignments: Löfgren A or B and Stevenson.

Those same tonearm manufacturers choose between different but " standard " tonearm efective lengths: 9", 10", 10.5", 11" and 12".

 

So run 5 times the VE calculator and you will know how measures the 90% of audiophiles tonearms. That's it.

R.

Most of us understand that measurement is the only way to actually know what is going on. Which is a theoretical argument in itself, seeing as probably no one who uses this site with any frequency has the equipment to do such measurements.

I am just interested in others’ numbers, in the vinylengine calculator.

Has no one here used it, or is it rather that no one feels obliged to post their numbers? Just curious.

 @ lewm 10+, Trying to calculate distortion this way is fruitless and hopelessly inaccurate. If anything you are interested in total distortion which is additive based of a host of factors. If you really want to know what is going on you have to measure. The same holds true for resonance frequency. The equation for resonance frequency relies on all reported values being accurate. Life does not work that way. It is easy to measure the resonance frequency and know exactly what is going on. Distortion, IM and Harmonic, is a bit more complicated and requires certain equipment which most of us do not have. 

I use lofgren B. It results in less distortion over most of the record except at the very inner grooves which most engineers avoid now a days. The SmarTractor gives you all the alignments and allows you to adjust overhang and offset to achieve reasonable results in most cases. 

 

Good point, lewm. I will reword my question:

Does anyone have the theoretical figures for your tonearms’ maximum distortion % and maximum tracking error degrees, based on the vinylengine Overhang Shift Calculator?

Both you and Raul referenced the same algorithm on Vinyl Engine.  I see where it has a readout for distortion once you plug in the known values for any particular tonearm, but I have no idea how it comes up with distortion %, mathematically.  I guess it uses formulae first promulgated by the gods of alignment, Lofgren and Baerwald. Anyway, sorry I cannot respond to your actual question. My feeling is that distortion has to be measured, not predicted based on angular errors,

Does anyone have their tonearms’ figures, re: max. distortion % and max. error degrees?

@fusian : Here the calculation. For a protractor you can contact MINT-LP and he will makes a dedicated protractor for your today TT/tonearm, ask him for Baerwald alignment. It’s really accurated and not an expensive protractor:

 

https://www.vinylengine.com/tonearm_alignment_calculator_pro.php?arm1=Arm+1&l1=ps&a1lv=225&a1=la&oh1v=&oa1v=&arm2=Lofgren+A&l2=ps&a2lv=225&a2=la&oh2v=&oa2v=&arm3=Lofgren+B&l3=ps&a3lv=225&a3=lb&oh3v=&oa3v=&arm4=Stevenson&l4=ps&a4lv=225&a4=st&oh4v=&oa4v=&rs=12&rsv=&og=iec1&ogv=&ig=iec&igv=&cal=y&submit=calculate

Right now I am using the HiFi news test LP protractor, just because it is handy. Does anyone know what alignment it is?

And I am mostly curious what the figures are for the tonearms of folks like you? Just because this is a new area of exploration for me and it might help me get a better overall concept of what is going on and how important the numbers are.

My ears are pretty good (professional orchestral musician who is a bit obsessed with tuning perfect intervals, including overtones). But my listening room has never been really ‘tuned’.

Dear @fusian  : I don't know which kind of alignment you are trying to use.

 

Löfgren A/baerwald ( IEC standard. ) gives you a little lower distortion levels : 0.61% and 0.4% respectively with maximum tracking error 1.78°.

Now, it's not easy to be aware of the true quality differences you are listening between that average distortion 0.73% and 0.4%. To be aware of it your room/system has to has a very accurated high resolution and " educated " ears.

 

Regards and enjoy the MUSIC NOT DISTORTIONS,

R.

 

I’m trying to make careful measurements, but only using a metal ruler - nothing fancy - and plugging the measurements into the vinylengine “Overhang Shift Calculator”.

https://www.vinylengine.com/tonearm_alignment_calculator_pro.php?arm1=Grace+222mm&l1=ps&a1lv=222&a1=cu&oh1v=15&oa1v=21&arm2=Grace+225%2F15&l2=ps&a2lv=225&a2=cu&oh2v=15&oa2v=21&arm3=Grace+225%2F12&l3=ps&a3lv=225&a3=cu&oh3v=12&oa3v=21&arm4=Grace+225%2F10&l4=ps&a4lv=225&a4=cu&oh4v=11&oa4v=19&rs=12&rsv=&og=iec1&ogv=&ig=iec&igv=&cal=y&submit=calculate

 

 

That has been a very popular subject here lately.  How are you calculating distortion?