Uni-Protractor Set tonearm alignment

Well if Raul's tonearm works out as well as the phonolinepreamp, we can call it Edsel

Probably it needs some extra steps

Enjoy the music

Dear friends: I know for sure that many of us does not understand in deep the geometry cartridge/tonearm set up with both Löfgren solutions/equations and this fact is normal even some tonearm designers did not either, I know this because I asked with no certain responses.

The Löfgren equations, as I posted , are the only ones that exist that as a main targets are to calculate overhang and offset angle due to three input numbers ( tonearm effective length, most inner and outer groove distance. ), the calculation needs no other single input number and this fact is similar for the other clones/Copy solutions ( Baerwald, Stevenson, etc, etc. ).

We don't need any other geometry parameter to make a tonearm/cartridge set up: effective length, overhang and offset angle are all we need. Even we don't have to care on the null points.
The null points are calculated and used for other things than stylus-cantilever/tonearm geometry set up.

The Stevenson A cloned/solution ( adopted by several Japanese tonearm manufacturers. IMHO with out in deep analysis. ) is not something with " new " equations, Stevenson only wanted that at the inner groove the tracking error be cero so he taked one of the three input numbers ( in the Löfgren formulas. ): most inner grove distance as one null point and that's all.
This " solution " gives you almost cero tracking error/distortion in the last 30 seconds of a LP with a higher distortions on all the remaining LP surface than in any other " solution ".

Any one of us can change ( in the Löfgren equations. ) this same input number and Voilá! we have a " new " Perry/Jones/Lopez/etc solution!!!.

Till today, IMHO, no geometry set up solution beats the Löfgren ones.

The Löfgren solution passed ( and is. ) trhough a Optimization process ( minimax principle. ) to achieve the criterions that I posted in my Thuchan answer.

Today there is no known equations or process that outperform the Löfgren optimization formulas to calculate: overhang and offset angle in a pivoted tonearm in static playback conditions.

Regards and enjoy the music,
Raul.

Dear Genesis168: That's why any decent protractor helps for the set up, that's why the 20.00 one that I'm using right now and the 2.00 that use Downunder works wonderful.
We need only that the choosed protractor be " aligned " by/under Löfgren approach, if fulfil this approach then that single protractor is all we need to make the set up in any pivoted tonearm and with any cartridge.

Downunder: got it?

Regards and enjoy the music,
Raul.

Dear Nandric, any tonearms performance is always in the ear of the subjective beholder. Furthermore it is dependent on a lot of periphery components which do have effects and (hopefully) synergies. An objective judgement in audio is impossible.
What is possible however is a geometrical alignment which strives for perfection. It is a matter of technical gear and precision.
As not all tonearms feature the very same design, nor do all 12" records feature the same grooved area, we have some tonearms which do gain in their performance (here: level of distortion and locations of peaks) from certain alignments which do take into account their individual parameters.
Furthermore - and often missed - when Löfgren and Baerwald made their calculations and did "choose" the arcs they did, it was many years before Robert Fine packed tremendous dynamics into the last 1/2" before the paper label of a Mercury SR-90313 or DECCA decided that the entire Daphnis & Chloe can be cut on 1 single 12" record.
Track a SR-90313 with a FR-64s aligned to Löfgren B and it will match the worst experiences you ever had at the dentist.

Precise alignment is the one - single - topic in analog audio, which is objective. It is simple geometry.
Apply it with a minimum of care and precision and it will give any cartridge and any tonearm the basic chance to shows it's best.
Honestly - there is no problem at all here.
The only one maybe that I do not like to generalize - and I know why and have found good reason.
If Löfgren (A or B ) or Baerwald suits best on all tonearms and records for some audiophiles - fine with me.
But thanks to secularisation, neither I nor anyone else has to follow Galileo's path of pain and revocation against better knowledge.
Cheers,
D.

Raul, I don't think lofgren is the solution to all tonearm alignment. That's why other geometries exist. Dertonarm is giving us other options. If you are happy with lofgren them fine by me. If you are happy with the $20 protractor and mm cartridges fine but for those who choose to buy this tool, fine with me why argue and step all over something Were all different and we have a choice. Not everyone likes hamburgers and fries. You preach distortion so why not use a Japanese pioneer?