While searching for my sl1210mk5´s arm design data I found different results for null points. According to Vinyl Engine tonearm database, null points are at 58.5/113.5 mm. According to www.cartridgedb.com, null points are at 63.5/105.0 mm.

I´m confused. Which pair of null points should I use in order to align my cart? Which pair is compliant to the Stevenson method used by Technics? Baerwald? Lowengreen?:dunno:

Thanks in advance for any clue!

Cyro:music:

I'd go with Vinyl Engine's recommendation. Or, you could just measure 52mm from gasket to diamond tip, mount it square in the headshell and be done with it - which is Technics' standard. The other link appears to be a forum board where people can submit their own information. And we know how unreliable a bunch of geeks flapping their gums about audio gear can be. :D

There's no 'correct' answer to null points...just personal preference, really. At some point during the swing of the arm's arc with any accepted tonearm geometry, there will be two null points. Where a person prefers them is part conjecture, part fact of matter and part voodoo. :D

While searching for my sl1210mk5´s arm design data I found different results for null points. According to Vinyl Engine tonearm database, null points are at 58.5/113.5 mm. According to www.cartridgedb.com, null points are at 63.5/105.0 mm.

I´m confused. Which pair of null points should I use in order to align my cart? Which pair is compliant to the Stevenson method used by Technics? Baerwald? Lowengreen?:dunno:

Thanks in advance for any clue!

Cyro:music:
The null points for this arm the way Technics intended are 58.5/113.5. The other set is for the older original (MK1) arms.

They are achieved by using the Technics alignment (overhang) gauge, which is available for a few dollars at kabusa.com. Or you can achieve the same thing by doing as Sansui Louie suggested and using the following measurement, which also appears in the manual.

http://i189.photobucket.com/albums/z81/hakaplan/TechnicsOverhangcolor1a.jpg

Alternately you can use the Stevenson, Baerwald or Loefgren protractors if you like--these were simply different opinions of which points would produce the least distortion over the course of the record. But the Technics method produces the sound that Technics liked and it's certainly the easiest to do.

Yes, and everything I know I learned from Howard...even the bad stuff! :D

Ok! I will use the Technics overhang gauge. After all it is the arm/tt project designer. Thanks Sansui Louie and Howard.

But considering I have to twist-move-back-and-forth cart in the headshell when using two point protractors maybe I will be off the 52 mm distance after reaching cantilever alignment. What is most critical for better sonic performance, to reach cantilever alignment or to preserve the 52 mm overhang?

I think the idea is that if you are 52mm gasket-to-diamond tip and are square in the headshell, your cantilever alignment will be correct.

If you were to use Baerwald geometry on your arm (which isn't wrong, just different), you'd find that your cartridge would sit a little further out towards the front of the headshell and tilt slightly in.

Ok! I will use the Technics overhang gauge. After all it is the arm/tt project designer. Thanks Sansui Louie and Howard.

But considering I have to twist-move-back-and-forth cart in the headshell when using two point protractors maybe I will be off the 52 mm distance after reaching cantilever alignment. What is most critical for better sonic performance, to reach cantilever alignment or to preserve the 52 mm overhang?
The goal here is to produce a set of null points, or a certain geometry, if you will. There are various tools one can use depending on which set of points one decides to use. If using the Technics points, you use the 52mm diagram. That's it. You've achieved it. Forget moving the cartridge back and forth or anything about any protractor.

If you use a protractor, like Baerwald, you then move the cartridge back and forth and finally reach the proper position. It's going to be in a different position than the 52mm method, because you're using different null points. And that's it. One method has nothing to do with the other method. If using anything other than Technics's method, you ignore the 52mm.

Not to "undo" anything that has been said so far, but I would like making some "assumptions", and Howard, please correct me if I'm wrong.

Just so all of us have a better understanding, and I myself am wishing to learn (at least about the Technics) OK, here goes.....

So then, by setting the Stylus with provided Plastic Jig, or a good ruler, to 52mm, can we then assume that the correct Null Points aformentioned from the VinylEngine Database will be correct? (or at least very close?)

Of course we'll all agree, the set it close, and "fougettaboutit", like Ron Popeil, "set it, and forgetit", we know just ain't gonna get it, but to the original poster, yes, aligning the cantilever is what you "supposed" to do, and extreme accuracy, aligning the Cantilever to a null grid is gonna get the Cee-Gar.

It's amazing, how Analog was basically crap (A relative term of course) during the 50's, and 60's, yet the medium held so much great potential. Problem was, nobody's system back then (unless you had the money of Howard Hughes) could extract the fidelity on these older, fantastic Discs.

We've come a long way! The better your alignment, the better your sound. If you cannot extract what's on the groove, you cannot expect downstream components to repair, or enhance what is initially lost from the transducer, the Cartridge.

The question is, is how far is one willing to seek the best playback? What components, what tools, what exacting precision to set up such components?

I do know the other side of the coin, meaning, one can fret, and loose sleep, but then lose the most important aspect about this hobby, enjoying the music!

As I close, try what was suggested earlier, "the boys" are here, and will help you, if any other problems arise. Mark

Trying to resume I would say I have two mutually exclusive alignment options: let´s say "two null points method" and "Technics 52mm method" (which is implicitly another two null points method). Both do the job and here we reach the relevant point raised by Mark: accuracy (more accuracy meaning better sonic perfomance, I presume). Which one is the most accurate method? Maybe there is a theoretical solution but since the final objective is enjoying the music I think the final judge is experience. I will try both alignment methods and go for the one playing the most pleasant result to my ears! BTW have any of you tryed MintLP protractor? It´s suposed to be one´s specific tt dedicated tractor. Really? Does it worth spending $110?

Thank you Sansui Louie, Howard and Mark for sharing your wisdom.
Cyro.

So then, by setting the Stylus with provided Plastic Jig, or a good ruler, to 52mm, can we then assume that the correct Null Points aformentioned from the VinylEngine Database will be correct? (or at least very close?)

That is correct. It should be right on the money.


Of course we'll all agree, the set it close, and "fougettaboutit", like Ron Popeil, "set it, and forgetit", we know just ain't gonna get it, but to the original poster, yes, aligning the cantilever is what you "supposed" to do, and extreme accuracy, aligning the Cantilever to a null grid is gonna get the Cee-Gar.
For ease of use, the instructions are to keep the cartridge square with the headshell. More accurately, the cantilever should be kept parallel to the long axis of the headshell. Done that way, it is equally accurate to any other method used. What you are doing in this case is setting the cantilever at the 22 degree offset angle. The 52mm sets the stylus at the position to result in the published effective arm length. Done this way, you accurately achieve the Technics null points.

For some reason it is believed that painstaking use of a protractor produces pinpoint accuracy, while using a quick jig is just so-so. Not so. They produce the same level of accuracy for the null points for which they were designed if used correctly.

Trying to resume I would say I have two mutually exclusive alignment options: let´s say "two null points method" and "Technics 52mm method" (which is implicitly another two null points method). Both do the job and here we reach the relevant point raised by Mark: accuracy (more accuracy meaning better sonic perfomance, I presume). Which one is the most accurate method? Maybe there is a theoretical solution but since the final objective is enjoying the music I think the final judge is experience. I will try both alignment methods and go for the one playing the most pleasant result to my ears! BTW have any of you tryed MintLP protractor? It´s suposed to be one´s specific tt dedicated tractor. Really? Does it worth spending $110?
See my response to Mark. One is not more accurate than the other. If done correctly they are equally accurate.

There will always be two points on a record where distortion is zero and there will be distortion everywhere else. The goal is finding the two points that result in an acceptable sound over the entire play of the record. Manufacturer's engineers had their idea of what they should be, as did Stevenson, Baerwald, Loefgren, and others. It is up to the user to determine what sounds the best to his ears. I recommend starting with the mfr's points, because for newbies that's the easiest, and to most people's ears it sounds fine. They wouldn't have sold the number of tts they did if it didn't sound good. And back then, no one talked about protractors. Everyone bought new tts and used the jig that was included.

No protractor is worth $110. In fact, the only one worth buying (if you want to use Baerwald and are willing to wait a month to receive it) is the mirror protractor from turntablebasics, because it enables you to see more clearly the position of the cantilever. Other than that, they are all the same, and the difference in error between a printed one from VE and a $110 one is meaningless. If the null point is at 120 or 122, I assure you that makes no difference, and if you can hear the difference, your name is Clark Kent.

Thanks Howard for the insight on protractors. Just saved me a hundred $$$.
An interesting useful tractor is the one included in the HFNews test record I own. Actualy there are three tractors: 2point Baerwald, universal and a linear offset "technique". Time to google for Stevenson´s, Baerwald´s and Loefgren´s papers.
Thank you all. I´ve learned a lot from you. Cyro.