Will SME-V, etc benefit with non-stock alignment?


Hi,
it was suggested by some most knowledgeable member(s) on the subject of tone-arm alignment, to start a dedicated thread for 'fixed' stylus-to-pivot measurement arms.

To my knowledge those would be ALL SME arms, as well as ALL Linn arms -- there might be others.

The issue in particular is the method of overhang adjustment by moving the pivot (bearing arm post) a la SME to accommodate slight variations in cart design. Linn does not even offer that (go buy their cart(s), and get a life :-)

In the case of SME, the expected mounting hole to stylus tip distance being 3/8" or in more 'current metrics' 9.52 mm. (sorry not US quite as yet, i.e. both are valid)

If a cart has this design criteria, AS WELL AS! the cantilever in the centre AND STRAIGHT with respect to the cart body / mounting screw holes, and more recently all with a tapped thread in it, they would HIGHLY qualify, or?
BUT, how do you see, or know this is the case in the first place, when purchasing a cart?

Given ALL is right-on within spec. you then are 'stuck' with the alignment that, e.g. was decided (for you the purchaser).
As soon as you'd like to try some other alignment scheme, and there are some: Löfgren A (Baerwald) -- the SME point of view/choice, Löfgren B, Stevenson, plus in fact you may make up your own, that may be to your liking. BUT NOT with any of the 'fixed' type arms, since it'll play havoc with the arms intended alignment geometry. (Ask DerTonearm if you don't believe me. He'll give you the low-down right to the 100th of a millimetre!)

So far, so good. You can go to one of the expert template makers, state your case, give your cart and arm parameters and ask him to make on for you. 100$ ---- to 500$? somewhere around there.
BUT WICH alignment then please?!

One you think is better? The same? Why bother for the same?!
And IF different, will it actually work for you?

Well, if not, go spend some more 'greens' on the next try?

Of course if you are aware of these issue, you just go and buy another arm, right?
Hallo, but what about synergy for SME decks, ditto Linn decks and arms?

So hope to have made the point sufficiently clear. So let's see what we can learn, that we do NOT know as yet.
Could get interesting, I hope so.

But please keep it informative and don't come tell us a dentists drill will be a better choice than XYZ tonearm choice.
Thank you for reading,
Axel
axelwahl
Jonathan :-)
you can cheer me up, thank you for your kind words.

If I talked about a difference, it is a small difference. The cart would not work properly if it was major --- but lo and behold MOST easily noticed when you swap a cart in an SME arm (fixed hole position and all). So I would have to guess and say, it was a ~ 0.5 mm variation. Looking at the two easily notice by a trained eye.

Now look at your quoted +/- 0.3 mm tollerance that takes care of a 0.6 mm variation alone (worst case), now I guess I'm making even MORE sense.

Good talking to you,
Axel
Fair enough, Axel. Thank you.

BTW, please note that applying tracking force to a cantilever will extend the stylus position forward by a small but noticeable amount. This is why Bob Graham's gauge uses a see-through crosshair piece that is weighted, to ensure that the stylus receives enough vertical force to shift it into the right location.

Ideally, Bob should add some kind of force or weight adjuster to his gauge so that it can be dialled in precisely for cartridges that have different tracking force requirements. Also there should be some type of height adjuster to enable the crosshair piece to remain in a horizontal state regardless of the cartridge height. But this, I suppose, belongs in a different thread - perhaps "Will Grahams, etc benefit with....." ;-)

regards, jonathan carr
Hi Jonathan,
still at it I see. Me, I'm just done with breakfast :-)

Your points made about the Graham are very good!
Pity I don't have one --- the thread is after all about the SME-V which is what I use.
But still a very good point, particularly once we start accepting that 0.01 mm are of any major? import.
Me, I'm not yet convinced, it would relinquish all 'fixed' stylus-pivot measurement arms to the scrap-heap, not so?

And as regards to the Graham, this alignment facility (marvellous as it seem) comes with additional connection points and might just undo what was gained by some hyper-accurate alignment.

I'm surmising, as I have not had an opportunity to compare a well 'stock' set-up SME V with a e.g. Phantom.
Also SME V's have not (to the very best of my knowledge) gone through that multitude of changes as did the Grahams. One sign of a good initial design is that it LASTS. Do you agree, or am I sounding too conservative here?

Greetings,
Axel
Yip urged me to do my own measuring, I un-mounted my Lyra Skala to measure yesterday and mine is close to 10.5 mm.
So, if you're looking for something other than a ballpark number you might want to do your own measuring.

Mike
Holy momma,

I declare, that's gotta give Jonathan some'm to say, and then some!

He is quoting +/- 0.3 mm from 9.52 mid-point (the IEC, hm... Gold-Standard as we have it right now) - and now this here situation.
10.5 mm! You can only make this yet more by adding VTF!

So this 10.5 mm is for sure from centre screw-hole (across the two hole-centres and midpoint between them) to the stylus tip, are we quite sure there?

So now what's next?
(I hope not turning in a version of Dynasty like my other thread :-)
Axel