Time to choose: Baerwald, Lofgren, Stevenson ?


I’ve managed Dr.Feickert Analog Protractor for a decent price (build quality is superb, such a great tool).

Time to play with Baerwald, Lofgren, Stevenson alignments on my Luxman PD444.
Need advice from experienced used of the following arms:
Lustre GST 801
Victor UA-7045
Luxman TA-1
Reed 3P "12
Schick "12

Baerwald, Lofgren, Stevenson ? What do you like the most for these arms?
Manufacturers recommend Baerwald mostly. 

Dedicated "7 inch vinyl playback deserve Stevenson alternative, maybe?
Since it's a smaller format than normal "12 or "10 inch vinyl, it's like playin the last track's according to position of grooves on '7 inch (45 rpm) singles. RCA invented this format, i wonder which alignment did they used for radio broadcast studios.   

Thanks

128x128chakster
Hi Lew,

I get that Stevenson has a significantly higher offset angle difference from (for example) Baerwaald than Baerwald does to Loefgren.  Re-reading my earlier post, I didn't make that clear.

I'll file this away for future experimentation, but know that my preference for Baerwaald over Stevenson is such that the effect you've observed would have to be significant to drive me to revert to Stevenson on such an arm.

Is it possible? Sure, and I'm always ready for a surprise.

Cheers,
Thom @ Galibier Design
Something just occurred to me:  Is the offset angle required for Stevenson much more acute than that which is required for Lofgren and Baerwald?  I think it's the opposite, because of the aforementioned need to twist the cartridge inward on a Stevenson tonearm aligned for L or B. This would mean that there is more skating force at the null points with these latter two geometries, compared to Stevenson.  That would be a point in favor of Stevenson.  Just a thought.

Dear @jtimothya : It's not M.Fremer or any other reviewer or tonearm designer whom started to " discuss " about, no.

All kind of alignments ( even personal ones. ) equations calculations ( Löfgen was the first one. )  shows three main set up parameters:

overhang, offset angle and two null points. These is inherent on all kind of alignments.

Why those two null points, other that tell us that there the pivoted tonearm cross tangentialy with "cero " tracking error?
Well, those null points define three LP surface areas where in each one exist ( normally ) diferent distortion levels. Where those null points been calculated define the distortion levels at those 3 LP surface areas : the area before the first null point, the area in between both null points and the area after the second null point. That's it. 

Rgards and enjoy the music,
R.
Something just occurred to me: Is the offset angle required for Stevenson much more acute than that which is required for Lofgren and Baerwald? I think it’s the opposite, because of the aforementioned need to twist the cartridge inward on a Stevenson tonearm aligned for L or B. This would mean that there is more skating force at the null points with these latter two geometries, compared to Stevenson. That would be a point in favor of Stevenson. Just a thought.
I’m not sure, but I believe so (Stevenson = more acute).

Last night, I looked a bit more deeply into the Elison spreadsheet.  The values for cells F3 and G3 are looked up in columns W & X.  I believe you need to generate a set of Stevenson figures for these two columns. 

My Excel chops are a bit rusty, but this much is apparent.  If anyone knows the answer to this, I'd appreciate it.  It might be time to contact John.

Darn you Lew! ... I have so much on my plate and yet this topic is really gnawing at me ;-)

Cheers,
Thom @ Galibier Design
Hi Chakster,

I'm with Raul - that if this concerns you, that you should experiment.  Even Lew stated that he felt uncomfortable about generalizing his resonance experiment across other tonearms.

Cheers,
Thom @ Galibier Design