end of side distortion

[richard l martin]

Hi. Can anyone recommend a protractor that will best help with end of side distortion please. I have an sl1200 mk2 with an at95 with a hyper elliptical stylus and i used an audio technica protractor. Thought all was good but i have recently noticed some irritating sibilant distortion on the last tracks. I just hate sibilant distortion! Thanks in advance Richard.

[Stratmangler]

Hi. Can anyone recommend a protractor that will best help with end of side distortion please. I have an sl1200 mk2 with an at95 with a hyper elliptical stylus and i used an audio technica protractor. Thought all was good but i have recently noticed some irritating sibilant distortion on the last tracks. I just hate sibilant distortion! Thanks in advance Richard.

Standard fit tonearm?
Could do a lot worse than this http://www.ebay.co.uk/itm/TECHNICS-SL-1200-1210-OVERHANG-GAUGE-CARTRIDGE-STYLUS-SET-UP-AID-/171016804377?pt=UK_Sound_Vision_Performance_DJ_Par ts_Accessories&hash=item27d1655819

[Qwin]

Technics use there own alignment/null points.

The closest is Stevensen alignment using DIN value for inner groove radius, this is very close and gives values for offset angle, overhang etc allmost as Technics spec.

I had similar inner groove distortion, tried several templates until I came accross Conrad Hoffmans program for generating templates. It worked for me.

Find it here: http://conradhoffman.com/chsw.htm

Third item on list of downloads.

[DSJR]

End of side sibilant distortion isn't *always* just due to misalignment although HE and line contact styli are very fussy of setup - try adjusting arm height and tracking force as well. Original AT95E's track at around 1.8 to 2g and the special HE version may need at least 1.5g for all I know. I have a Shure M91-ED style replacement stylus and this isn't anything like as good on hf tracking as the original would have been - much lower compliance too..

My advice from a distance would be to investigate the next tier up, something like an AT120E which, despite not having such a fancy tip profile, should have greater tracking limits and a well integrated bass if fitted to a low mass headshell. If a posh diamond profile is your thing, the AT440MLa is also a good match in a later model Techie 1200 tonearm.

[Qwin]

I agree that there could be things other than basic alignment creating your distortion. I found the anti skate level contributed to the distortion as well so experimenting there might help. (presuming std Technics Arm)

Still think you need to start with basic alignment though, before trying elsewhere.

The Audio Technica Protractor you used is probably a Baerwald alignment which I found totally unsuitable using three different protractors.

Technics uses its own alignment and for a pivot to spindle distance of 215mm results in an overhang of 15mm and an offset angle of 22 deg.

Baerwald produces an overhang of 17.8mm and offset angle of 23.7 deg.
I am no expert but believe that is the main cause of your problem.

The Stevenson Alignment I sugested gives an overhang of 14.93mm and offset angle of 22.1 deg, I said it was close.

I used this and after a bit of additional fiddling with the VTA and anti skate on the fly, managed to find the sweet spot of my Ortofon 2M Red. My veiw of this cartridge has changed, I am now hearing what it can achieve for the first time and without any ESD.

I would try this first, it costs nothing. ;)

[RobbieGong]

I actually prefer Baerwald and following the arc etc. Has always sounded good to my ears with the stock arm and now my Micro Seiki MA 202. Can someone remind me which protractor (Stevenson, Baerwald ?) jap arms are generally set to ??

[richard l martin]

thanks everyone i have taken all of your advice on board and will try a Stevensens protractor. I seem to have experienced these problems for many years and i am now considering a linear tracking turntable but i cant afford an expensive one. Would say a Technics one be better in terms of ESD ? Any one have any thoughts on this? Kind regards Richard.:scratch:

[Barry]

The Technics SL1200 Mk II arm has the following geometry:

Length, pivot to stylus: 230mm
Length, pivot to centre of TT: 215mm
(thus) Overhang: 15mm

Offset angle: 22 degree.

The geometry therefore corresponds to neither the Baerwald nor the Stevenson prescription.

To minimise the tracking angle error, the overhang needs to be adjusted so tangential tracking is achieved at the two radial null-points 58.8mm and 113.5mm.

Cartridge/arm misalignment will affect 'end of side distortion' far more than incorrectly setup bias.

[Qwin]

Hi Barry,
you pretty much repeated what I had pointed out.
Trouble is there isn't a Technics protractor using their geometry. At least I don't think there is, never found one myself.

The Stevensen is within o.1mm for overhang and 0.1 deg for offset, all be it at slightly different null points.
I doubt any of us could set it up to that level of accuracy anyway and it would still be more acurate than the plastic thingy Technics made.

The trouble with the plastic gauge is it depends on the arm "S" bend being bent EXACTLY right - have you ever tried bending tube to that level of accuracy? Also that there is no error in the fitting of the headshell connector or thickness/compression of the complient washer. At least a protractor ignores all these elements and addresses whats hapening at the actual point of contact.
In the absence of anything designed for the job I think the Stevensen protractor is the next best thing and the one to use.

Boy am I glad I'm going to a linear tracker soon. :D

[Barry]

Hi Ken,

Yes, we are in close agreement; though the figures I calculate for Stevenson are 22.6 degree offset angle with 15.89mm overhang and for Baerwald 23.97 degree and 18.05mm. Similar to your values.

Agree bending the arm tube to precise angle, and allowing for relaxation is difficult. Apaparently Breuer observed the relaxation in bent arm tubes over several months - and then decided to abandon bent arm tubes for his own arm.

In my experience, the Japanese tend to "do their own thing" when it comes to pivoted-arm geometry, but in general the geometry they choose is closer to Stevenson's prescription than either Baerwald or Loefgren.

As is in all things audio, it is often best to let your ears decide.

Certainly tangential tracking arms are devoid this problem - but have their own shortcomings.

[Qwin]

Richard - Does ESD play a part in Linear trackers?

Not heard of that.

This is the Arm I am going for (It will fit on an SL-1200 variant).

http://www.trans-fi.com/terminatortonearm.htm

I may well draw up a protractor myself its a piece of pish but I don't have access to a CAD package, might be possible in Corel Draw but a challange.
Hardest part is doing the Maths, but that has allready been done. We know where the null points are and the overhang curve, angle etc. Suprised no one has done this Mmmnnn..... Am I missing something :scratch:

[Qwin]

Hi Barry,
You have used IEC standard for inner groove radius for Stevensen values. If you use DIN values you get my results which are even closer.

I'm not being clever with the maths here, I am just reading off what Conrad Hoffmans program calculates, like I said, I'm no expert. Check the program out at the link I gave on post #3. Very usefull. ;)

[Stratmangler]

The trouble with the plastic gauge is it depends on the arm "S" bend being bent EXACTLY right - have you ever tried bending tube to that level of accuracy?

Matsushita are a serious major player in Japan - they will have the bending issue nailed.
It ain't yer average tinpot engineering shop ;)

[Qwin]

Ok I've drawn up a protractor for the standard Arm using the stated Technics values of:

Pivot to Spindle = 215
Effective Length = 230
Overhang therefore = 15
Offset angle = 22 Deg
Inner null point = 58.8
Outer null point = 113.5

I have saved this as a PDF document and it prints at 1:1 providing you have scaling set to NONE on the PDF printing window. I have added horizontal and vertical dimensions to check against.

I will check it works tomorrow on my deck. If every thing is Hunky Dory I will find a way of posting it so everyone can find it easily.

[The Grand Wazoo]

Good work if it works!
If you'd like to email it to Nick (Beechwoods), Barry or myself, we can get it uploaded into The Knowledge - the AoS Library.

[walpurgis]

Interesting. We have some clever people on AOS.

I would not have known how to do this offhand as I've never had to look into alignment protractor design.

[Qwin]

Chris - do you mean in a PM when you say e-mail?

like I said, I will check it out first, don't want to put something out there that doesn't work properly.

[The Grand Wazoo]

Yes, check that it works first & then PM one of us & we'll send you an email address for you to send it to.

[Barry]

Hi Barry,
You have used IEC standard for inner groove radius for Stevensen values. If you use DIN values you get my results which are even closer.

I'm not being clever with the maths here, I am just reading off what Conrad Hoffmans program calculates, like I said, I'm no expert. Check the program out at the link I gave on post #3. Very usefull. ;)

Stevenson does not explicitly quote the inner and out groove radii. He does however quote the two null-points as being 60.325mm and 116.992mm. From these one can back-calculate the inner and outer groove radii to be 54.821mm and 145.263mm.

These are similar to, but not identical with, the DIN standard radii of 57.5mm and 146.05mm.

There is no a priori choice of the inner and outer groove radii for a 12" microgroove LP. Whilst the outer groove radius is generally agreed to be 146.05mm (= 5.75"), the inner groove radius is up for debate.

Stevenson chose his figures as the best compromise for 7", 10" and 12" records.

Once the inner and outer groove radii have been chosen, the null-points are automatically determined and vice versa. From these the overhang and offset angle are then determined and depend on which of the three prescriptions: Baerwald, Loefgren or Stevenson, is followed.

Baerwald provides equal distortion at the start, finish and at a mid point across the record playing surface for records of constant diameter.

Loefgren provides lowest distortion for all radii between the null-points, at the expense of increased distortion at the start and finish of records of a constant diameter.

Stevenson claims to provide optimal tracking for all records of 7" - 12" diameter, with zero distortion at the inner groove (60.325mm), and at 117mm, at the expense of increased distortion elsewhere.

"You pays your money ....."

[Qwin]

Yep, agree with everything you quoted Barry. :)

If you use the IEC Standard on Conrad Hoffmans program it calculates the null points you stated Stevensen used.

If you use the DIN standard the null points, overhang and offset are closer to what Technics used.

Now I must state, I am using data for the arm on the Technics from the vinylengine database, they quote the inner null point of 58.8 and outer of 113.5 do not know where these figures came from but these are what I am basing everything on. Can anyone confirm these and give a source?

Technics must have had a reason for the direction they took, so to simplify the whole thing I have drawn up a protractor using their (quoted) geometry.
I will be testing it today.

[phonomac]

Hello all,
I've looked extensively at alignment options, using the tools at VE, and have concluded that a better set-up can be achieved using a minor tweak to the standard Technics alignment.

If you increase the overhang by around 0.6mm, retaining the spindle-pivot (which is fixed for the standard arm) and offset angle as standard, you will have slightly higher levels of distortion on the outer portion of the disc, in to the outer null, but from then on inwards on a par with or substantially better than all the 'standard' alignments.

Using the Conrad Hoffman template generator, with a reasonably high resolution printer (inkjet or laser) you will have a template with a very fine line for the arc. I then laminated mine, so with a smooth surface you can allow the stylus to contact the template. With this setup you can very clearly align the the stylus to within 0.1mm - you don't need to estimate 0.1mm as a error, you just need to look at deviation from the arc which you can assess as fractions of the line width.

regards

Angus

[Qwin]

I tested the protractor I drew up this morning and it works great.

Used an Ortofon 2m Red (Elliptical stylus) and a Goldring 1042 (Gyger S fine line stylus).

Run them on several LP's and concentrated on the end tracks. It works well with no sign of ESD.

I have also written instructions on how to use it for those who are new to cartridge alignment.

Should appear in "The Knowledge" soon ;)

Tried overlaying it on the Stevensen using DIN standard for inner grove radius that I plotted off the Conrad Hoffman program - there is a very very small difference between the two. :)

[serendipitydawg]

"Should appear in "The Knowledge" soon "

Did this ever happen? I had a cursory look and couldn't find it.

I found this thread via Google because I want to set up one of two SL1200's abandoned in my spare room by my son, as a dedicated mono turntable.

[Qwin]

Well if it was put in the knowledge, its not clear to me how to find it.

So here are the links to the instructions and protractor PDF I drew and which are held on my website.

http://www.jkwynn.co.uk/Pics/Instructions for Technics Protractor.pdf

http://www.jkwynn.co.uk/Pics/Technics Alignment Protractor.pdf

Hope you get a good result :)

[serendipitydawg]

I've bookmarked this thread & will print out the protractor & align a cartridge over the weekend.

Not sure what it'll be yet; a hot favourite is a pristine Grado F1+ I found in a box in the attic recently.

I will report back in due course.

Thanks again

[walpurgis]

I've mentioned this before. Be careful printing protractors, they don't necessarily come out quite to scale, rendering them useless. Try and find one with dimensions shown so you can check once printed.

[Macca]

I can't see mono makes any different for a stock SL1200 you need the technics alignment gauge to get it spot on. It doesn't use any of the standard versions.

[Qwin]

The instructions cover checking the size the template prints at and there are fixed dimensions I added to check against.
There is no protractor for the Technics, just the one I drew. Technics do not use any of the usual alignments, they use their own.
This is why I went to the trouble of making one.

The plastic gauge is crude and does not take into account any of the numerous elements that can be out of alignment and give a false result.
All the plastic gauge does is set the stylus relative to the arm and not the record which is what counts.
A protractor gets the stlus to the right location and at the right angle regardles, you could even get a good alignment with a slightly bent arm.
This is why I prefer this method.

[Macca]

But assuming the arm is 100 per cent the gauge should be all that is required shouldn't it? I mean the location of the record is a fixed parameter.

[Qwin]

The record is the ONLY fixed parameter, subject to centre hole accuracy of coarse.
Just look at how many components and mechanical joints lie in the cartridges location.

Is the pivot point and the screw fixings for the VTA assembly in the right place?

Is the multi part pivot assembly concentric with this?

Is the plastic yolk that accepts the arm tube true and is the tube the right size/angle to fit?

Is the arm tube true, I had three and they were all different to a very small extent?

Is the Head shell connector mounted true in the arm and does the Head shell washer compress uniformly to keep the headshell true to this?

I think you can see why I worry about this method, there is a massive tolerance stack and opportunity for error, more angular than length, though could be both.

If everything is perfect the plastic guage will work, but there is no way of checking, short of using an alignment protractor to confirm it works, and that would have to use Technics geometry.

You could bend the the arm at a right angle in the middle and still line the cartridge up with the plastic guage, but it wouldn't be correct.
It's a basic tool for Joe Average to use when he first gets his turntable out of the box, thats all it was ever intended for.

Far easier just to use my protractor which uses Technics geometry.

[Lynster]

Thanks for publishing your efforts Ken. I've now tried your protractor with a Shure M95/SAS cartridge that is currently on my TT and I had already set up using the Technics plastic tool and the protractor made it so simple to do this. Great way to go for future set ups from scratch if using the Technics alignment.

Upon checking, it appears my existing set up was spot on and has always sounded great so the little tool can work well but then I may simply be very lucky and without any of the variables you listed applying in my case. However, whilst the tool can achieve an accurate overhang quite simply and quickly, I remember that getting the sides correctly aligned without an accurate printed grid to help took me ages.

Incidentally, I've always used the Technics alignment for two of my cartridges without having sufficiently long head shell grooves (standard Techy head shells) to accommodate and have used Baerwald for two others, one with a Jelco head shell and plenty of adjustment room. But I've always been very pleased with the standard alignment on the first two so I may start experimenting with the others now that your protractor adds to my set up accuracy.:)

[Qwin]

Lynton - Exactly.
Its good, even if you just use the protractor to check your arm/plastic gauge gives the right set up.
At least you can then use it with confidence.
If anything is slightly out it will show up and you can use just the protractor in future.
As you have found, if everything is spot on with the arm and all its fixings, the two methods should give exactly the same result.
You should be able to set the cartridge with the plastic gauge then put the cartridge over the correctly positioned protractor and the stylus should line up with both null points at the correct angle.

I've been perdantic with the explanations in these posts so that any folks inexperienced at cartridge alignment can understand and benefit from them.
I think if you look at the way I have drawn the protractor, I have left all the critical arcs and angle construction lines, it helps folks understand why the cartridge changes angle as it sweeps accross the record and how it is at right angles to the groove only at the two null points.
It certainly helped in my understanding.

If anyone is interested in how much difference there is between Technics and Baerwald alignment, check out this drawing I did, where I have overlaid the two alignments:

http://www.jkwynn.co.uk/Pics/Technics v Baerwald.pdf

Its strange how the grid squares line up, even though the effective length, null radii and offset angle are different between the two, but thats Maths for you.

Do not use this for setting up a cartridge, it will be confusing, stick to using the instructions and protractor on post #24. :)

[serendipitydawg]

I've bookmarked this thread & will print out the protractor & align a cartridge over the weekend.

Not sure what it'll be yet; a hot favourite is a pristine Grado F1+ I found in a box in the attic recently.

I will report back in due course.

Thanks again

It took until today to find time to use your protractor in earnest, Ken.


It all went according to plan except that it took much longer than anticipated.

My initial observations:

1) I am not sure my alignment skills are fully formed. So I will check it all again, tomorrow.
2) I need to get my eyes tested. And stop relying on pound shop reading glasses:)
3) I am amazed at the differences in sound quality caused by different mats. Initially I just used a bootlg Technics logo one
that was left with the deck. Then a sorbothane mat found with the Grado F1 plus cartridge in the attic. Finally a cork & rubber compound one that I bought cheaply on eBay to go with a Thorens TD160 I have. Better & better sound as I changed mats.

Still a work in progress then. More later

[walpurgis]

Takes me moments to adjust alignment and I never get mistracking with any cartridge. I just use a forty year old card protractor that came from an ancient Hi-Fi magazine. I've got fancy ones, but don't bother with them. And I use cartridges that are not cheap!

[struth]

Ive used a geo disc for years. works fine and is easy to use....am on my second one actually.

[indy]

Qwin
Tnank you for your ideal protractor ! Because I've also had the Inner Groove Distortion in the end of record's side on Technics SL-1210Mk2 when using by stock Technics gauge and Baerwald alignment protractor.

[Haselsh1]

3) I am amazed at the differences in sound quality caused by different mats. Initially I just used a bootlg Technics logo one
that was left with the deck. Then a sorbothane mat found with the Grado F1 plus cartridge in the attic. Finally a cork & rubber compound one that I bought cheaply on eBay to go with a Thorens TD160 I have. Better & better sound as I changed mats.

Yes, I was too. I settled on a Funk Firm Achromat as this gave, in my system, the biggest change in sound.

[Qwin]

Qwin
Tnank you for your ideal protractor ! Because I've also had the Inner Groove Distortion in the end of record's side on Technics SL-1210Mk2 when using by stock Technics gauge and Baerwald alignment protractor.

Your welcome, glad it helped you.
I'm surprised more people don't use it, as far as I'm aware its the only one which uses the geometry and null points for the Technics arm. Technics use slightly different alignment to those normally used.

[Bacek]

For me end of side distortion desapired when I have switched from at95 to denon dl110 on same alignment. I have used template generator na Baetwald alignment.