Discuss The Viv Lab Rigid Arm

Dear @intactaudio : There is no :Whaaa?. This time you are way wrong/misunderstood on that specific issue .

 

" you need to specify at least four parameters which typically are alignment type, inner groove diameter, outer groove And Pivot to spindle (P2S.. ""

Wrong, you don’t need the P2S that in the standards alignment calculations is not and input parameter in the equations but on those calculations P2S comes only by the difference between EL substracting the calculated overhang and that’s it. P2S came after overhang calculation.

Been math on those original equations are manipulations, that everyone can " handled ", like the one made by the SAT designer chnaging the most inner groove radius and then following Lögfren A alignment that in theory achieves lower overall distortion level.

 

""" As a background note re the ’Löfgren A’ alignment and the null points. Null points are calculated from the inner and outer groove radii selected for alignment optimisation purposes. They are outputs only. They are not the drivers of the optimisation philosophy or arrangement, but rather the consequences of it. Of course, they may be specified for use in an alignment procedure or for when a particular alignment tool is being used, but their specification automatically pre-determines the values of the inner and outer groove radii.

For the ’Löfgren A’ solution, the null radii are dependent only on the selected inner (R1) and outer (R2) groove radii,....""""

 

I can’t paste the equation so I will try to write it for the inner null point for Barwald/Löfgren A/Stevenson B:

 

R1 inner and R2 outer groove radius.

 

2 x R1R2 division/ ( 1-1/ divided by the sqare root of 2)R1 + ( 1+1/divided by the sqare root of 2 )R2

 

That’s the original equation and you can infere from that for the outer null point.

 

Any one of us can have our self kind of alignment just changing the most inner groove radius and like SAT running Löfgren A calculations. Löfgren B is an " aproximation " ( this is the word used ) that is a little different form the alignment A.

There is a long historty on all those alignments and additions to those but the A alignment does not changed in its formulation of null points.

 

Effective tonearm length has no influence in the null points position. It’s are the same for a 250mm tonearm than for a 300mm one.

 

R.

@rauliruegas 

You have stripped all context from my original quote which was about the requirement of both overhang and offset to get two null points.   Without overhang which requires an effective length to calculate the two null points cannot exist.   

dave

 

 

@intactaudio : " was about the requirement of both overhang and offset to get two null points. Without overhang which requires an effective length to calculate the two null points cannot exist. "

 

That could be for you but not for Löfgren him self that was who specified that formula, it was not me and certainly not you but LÖFGREN.

 

As a fact to calculate overhang the most inner/outer values are necessary in the Löfgren A . Effective length is necessary for the overhang calculation but not for null points calculations. Again it’s not me but Löfgren in his A alignment.

 

R.

@rauliruegas 

specifying a formula and not understanding its relationship to the discussion at hand serves little good.  I doubt Løfgren would suggest it possible to get two null points without the addition of overhang no matter how much you point him to his math.

dave