Cartridge Alignment to Protractor Extremes

Discussion in 'Audio Hardware' started by avanti1960, Apr 3, 2021.

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  1. Cliff

    Cliff Magic Carpet Man

    Location:
    Northern CA
    I have been using a Mint protractor with my VPI Classic for around 6 years. I've mounted 5 different MC carts with it. If it's printed on the mirror, then I use it. So I put the stylus outside of where the record starts (near the protractor's printed arc starting point), check alignment to the arc and then move it near the spindle (far inside of any run out groove). I always figured if it follows that line all the way through, then that's as accurate an overhang as you can possibly measure for.
     
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  2. StratDoc

    StratDoc Sapien

    Location:
    Chattanooga, TN
    Got it thanks. Was having a brain lapse moment when I asked the question.
     
    Davey likes this.
  3. StratDoc

    StratDoc Sapien

    Location:
    Chattanooga, TN
    I was close on the alignment using the dbsystems protractor but when compared against the tool measuring the stylus across the arc from outside to inside was slightly off. Now dialed in!
     
    Davey likes this.
  4. avanti1960

    avanti1960 Forum Resident Thread Starter

    Location:
    Chicago metro, USA
    doesn't work for me. there is no guarantee that your eyes will be at the exact height needed to make sure they are lined up, there is no horizontal plane of reference.
    you could easily line up the stylus and line by eye and it will still be off.

    to do it by eye requires two reference points, one in front of the cartridge and one behind it. get the stylus in the middle and aligned and you're good.
     
    Henry J likes this.
  5. avanti1960

    avanti1960 Forum Resident Thread Starter

    Location:
    Chicago metro, USA
    sounds quite painful! hope all gets cleared up soon...
     
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  6. avanti1960

    avanti1960 Forum Resident Thread Starter

    Location:
    Chicago metro, USA
    FYI I just lined up a new cartridge with the diving board. I was very careful and sighted it in as best as I could using a straight edge and looking at it for several minutes. I was at least 2mm off compared to the protractor!

    Look at post #106. No muss, no fuss.

    Lyra Delos Phono Cartridge Questions
     
    woodpigeon likes this.
  7. StratDoc

    StratDoc Sapien

    Location:
    Chattanooga, TN
    All very fascinating to me. What is the difference between Lofgren A and B? I have now adjusted my cartridge for B. Sounds a bit brighter than the adjustment made with dbsystems only. Also the channel separation does not seem to be as distinct - now music sounds more like coming from the center.
     
  8. Davey

    Davey NP: Electrelane ~ No Shouts No Calls (2007 LP)

    Location:
    SF Bay Area, USA
    Just a different set of optimizations, Lofgren B has lower tracking error and distortion over most of the record, at the expense of the innermost grooves ... below from vinylengine for your 200mm pivot-to-spindle Pro-Ject arm ...

    [​IMG]
     
    Last edited: Apr 5, 2021
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  9. Sterling1

    Sterling1 Forum Resident

    Location:
    Louisville, KY
    So sorry it does not work for you. But, great that you have a means to get exacting alignment. The aids I have experimented with have helped me to get exacting results. The dial caliper and a combination square will get results where parallax is not a factor; yet, I have had awesome results with just a line on a piece of paper to discern a 52mm stylus to headshell distance.
     
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  10. Sterling1

    Sterling1 Forum Resident

    Location:
    Louisville, KY
    Reading all these posts it appears everyone here has a method to align their cart which yields a satisfying result; yet, it seems all wonder if that result might be improved. It's what makes turntable usage a challenge for those here who are kind of OCD.
     
  11. Davey

    Davey NP: Electrelane ~ No Shouts No Calls (2007 LP)

    Location:
    SF Bay Area, USA
    Still, that is just for overhang, hard to get the offset angle of the cantilever set close to perfect without using a protractor, and so why bother with the plastic thing and various helper tools if you need to use a protractor anyway, I think that is what some are saying. At least that is my observation from the sidelines :)
     
    KT88 likes this.
  12. Brucedgoose

    Brucedgoose Forum Resident

    Location:
    Hawaii
    You definitely want to try to maximize channel separation. That’s one of the most important characteristics you pay for in a good cartridge - excellent channel separation. If the change you’ve made reduces channel separation, you should try to get back to the old setting and move in the opposite direction.
    You’ll get maximum channel separation when the coils are hold symmetrically in the precise center of the groove and the cartridge is adjusted such that this perfectly centered position is retained throughout play, or as close to perfectly centered as the undulations of the groove and the inherent compliance of the cartridge permit. Listening for maximum channel separation seems like a good way to me to determine if you’ve got things set up optimally. In fact, when aligning a cartridge with an oscilloscope, which some hardcore do, the standard procedure is to observe the scope trace while adjusting and look for maximum channel separation on the scope.
    Now, don’t tell me you’re going to go out and buy an oscilloscope! :)
     
    Last edited: Apr 6, 2021
    clercqie likes this.
  13. TheVinylAddict

    TheVinylAddict Look what I found

    Location:
    AZ
    Next time, take your mittens off when mounting! :)

    2mm? Really? I know you're trying to make a case you prefer one method over another, but let's keep it real! How do you use a square, and still be 2mm off? Maybe you were flexing the body of the diving board with the square?
     
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  14. TheVinylAddict

    TheVinylAddict Look what I found

    Location:
    AZ
    Avanti - the diving board is included as a convenience for the uninitiated - there's no doubt it's tough to get dead nuts by eye with it. I mentioned earlier the distance between the body and the stylus tip is too great, and the parallax effect comes into play... one little tilt of the head....

    But the diving board does make a great cartridge holder to aid in getting it dead nuts --- like when you draw a line on paper, use a square (successfully), etc.

    The diving board is not a replacement for a protractor. Or vice versa. :) If I don't know the overhang / offset for a turntable, I have no choice but to bust out the protractor. Everything has its place.

    But in the context of Technics platform, the 52mm overhang that diving board is directing you toward - is going to get you pretty darned good sound, assuming you've got everything else right. So much so I stopped tinkering and use 52mm, cartridge mounted straight with the s-arm.
     
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  15. Sterling1

    Sterling1 Forum Resident

    Location:
    Louisville, KY
    It is not at all difficult, pursuant to Technics alignment scheme instructions, to square the cart/cantilever to the headshell.
     
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  16. Sterling1

    Sterling1 Forum Resident

    Location:
    Louisville, KY
    Exactly.
     
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  17. missan

    missan Forum Resident

    Location:
    Stockholm
    I agree, it's very easy if one is used to fine mechanical work.

    However I can think of some that would not be able to it good enough.

    As a whole though I think the importance is somewhat misunderstood.
     
  18. Sterling1

    Sterling1 Forum Resident

    Location:
    Louisville, KY
    Well, I’m literally half blind so for me fastening the cart to headshell is a challenge, even when the headshell is detachable. The challenge has in fact inspired me to consider buying an Ortofon 2M series PNP cart.
     
    Ingenieur likes this.
  19. woodpigeon

    woodpigeon Forum Resident

    Location:
    New Zealand
    I’ve found a transparent plastic set square, and a sharp pencil, to be useful companions to the Technics gauge.

    With a little pencil mark on the exact centre of the front of the headshell, stand the gauge up on its end and use the set square to line up the cantilever on a straight line between the notch in the gauge and the pencil mark in the headshell. Helps eliminate parallax error. This step is useful when the cantilever is off-centre preventing you from just squaring the cartridge in the headshell.

    After that check overhang length again from the side view.

    Repeat until both views line up.

    If you check that pencil mark from the front against a set square lined up with the notch, it’ll also help you confirm your gauge isn’t warped, which apparently can happen.

    At the end of the process the mark can just be wiped off.

    So far that seems to sound good for most cartridges. I’m just working this out based on what’s out there on the internet, trial and error, and what seems like common sense, so if this method is wrong someone will hopefully point out how!
     
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  20. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    I've resorted to making my own protractors and I get a local print shop to print them on a gloss card stock. Their output is absolutely spot on where my laser printer is not.

    One note about the arc protractor is that if overhang is right the stylus will fall on the arc at every point, not just the nulls. The reason you would work at the extremes is because that gives you more precision—it amplifies error.

    I'll also say that line width on the protractor is a factor. I use a .5 pt line width, but even that under magnification needs consideration of where on that .5 point line the stylus falls.

    Another good point is that with an arc, start on the inside close to the spindle, then swing out to the perimeter. If the stylus falls inside (pivot side) of the arc at the perimeter, move it a little closer to the pivot. If it falls beyond the arc on the perimeter, move the cartridge a little further from the pivot. That part seems a bit counterintuitive until you think it through.

    Note: In creating custom protractors I use Adobe Illustrator and auto-generate all the shapes so that the result is as accurate as the application can produce. That said, a CAD program has a degree more accuracy than this illustration program.
     
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  21. Ingenieur

    Ingenieur Just a dog looking for a home...

    Location:
    Back in PA
    You mean this set-up?
    I like it, supposedly perfect for the Technics.
    I'm thinking this 2M black plus black SL1500C.

    Length 52mm. Headshell with a 2M cartridge pre-mounted provides correct Baerwald alignment with the Ortofon TA-110/ TA-210 tonearms, likewise with the major part of tonearms with universal mount.

    Will this give a satisfactory alignment?


    [​IMG]
     
    Last edited: Apr 6, 2021
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  22. JackG

    JackG Forum Resident

    Location:
    NJ
    That’s a lot. What were you “off” against, the 52mm Technics recommends or some other alignment?
     
  23. JackG

    JackG Forum Resident

    Location:
    NJ
    Assuming the cantilever is straight, yeah? Seems not to be an issue with my A-T carts at least.
     
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  24. avanti1960

    avanti1960 Forum Resident Thread Starter

    Location:
    Chicago metro, USA
    it was off to the Mint protractor for Technics.
     
    JackG likes this.
  25. Sterling1

    Sterling1 Forum Resident

    Location:
    Louisville, KY
    yeah that’s the ticket. Mounted to the Technics it delivers the Technics tracking error scheme.
     
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