Tracking error distortion audibility

Dear friends: Now that we are here and that some of us are " playing " with the information there are one or two subjects that can/could help to understand what is happening or what we are listening when ( example ) we buy a new protractor ( any ) and now with the new stylus set-up everything goes " better " ( many times does not goes better but we think it did. ).

With the " calculator " ( extremely easy and informative. ) and everytime you change your tonearm effective length you can calculate the new tracking distortion ( % ), maybe/could be that what you like is higher distortion.

This is one point the other one is that when you change the tonearm effective length through an overhang change you are changing too the tonearm/cartridge resonance frequency ( and change the tone in the sound reproduction. ) and is part of the " new " sound you are listening.

Maybe you can think that 2mm of cartridge movement is not important but it is due that you made that change where the cartridge weight makes more difference in that resonance frequency calculation: at the headshell/farest from the pivot tonearm.
Other factor that affects specially on the tonearm/cartridge tracking capacity is that moving mass change with the cartridge position.. I don't know if it is well say it but what I mean is that the tonearm and the tonearm pivot works more " comfortable " when " see " the cartridge weight/mass nearest to it.

Regards and enjoy the music.
Raul.

Dear Raul, a very interesting point.

You are right - the effective mass does indeed increase when you move the cartridge away from the pivot/bearing. The position of a given cartridge does have some influence on the resonance frequency. Whether it is enough to really contribute to the sound itself has to be explored. The effective moving mass of a pivot tonearm is also (sometimes very drastic...) affected by the weight of the cartridges body (Koetsu's stone bodies.....) and/or the weight of the headshell (lightweight Orsonic AV-11 vs. FR S/3 for instance - a difference of over 21 grams !!!).

Both these units do "sit" at the very end of the "balance gauge" and thus do contribute very strongly to the effective moving mass.

Very interesting point indeed!

This too is one of thereasons why the torsion resistance of a tonearm is so important - the further away the cartridge is, the higher its influence on the mechanic resonance behaviour of the tonearm.

Raul and Dertonarm,
Does either of you have an opinion on whether or not the advantages of lower theoretical distortion of a 12" arm outweigh the disadvantages of greater moving mass and potential for slight stylus misalignment being amplified more in a longer arm?

I'm curious about the differences between the 9" SME V and the new 12" SME V-12. This topic is discussed by Michael Fremer in the latest Stereophile review of the SME 20/12 and I'd like to read your opinions. Thanks. Peter

Dear Peter,
we have to mate either tonearm with a cartridge with perfectly suitable compliance, - if done so, there will be no trade off in moving mass vs. effective length.
Given an ideal match with the compliance of the cartridge, we can assume almost identical conditions in terms of resonance frequency.
So the geometrical advantages of the 12"-tonearm will prevail.
The sonic advantages will be especially noteable on well recorded opera with comperatively large soundstage.
The sonic presentation of the soundstage will be much more stable and the positions of the various singers and their movements on stage will be more precise.
So - as I see it - there is no trade off between moving mass and geometrical advantage.
I do not want to call again and alone the example of the FR-tonearms (the FR-66 will always beat the FR-64s with any given FR-7 system), so lets go to Ortofon instead:

- do mount a SPU in a 9" Ortofon and in a 12" Ortofon tonearm. Both do have effective moving mass together with the SPU which will result in resonance frequency very close to each other (but it will be lower in the 12" Ortofon). Given exact mount and alignment to the same geometry (Baerwald, Loefgren, Bauer, Stevenson - no matter which, as long as its the same for both), the 12" will prevail in terms of size of soundstage presented, ease of tone and naturalness.
All these features are related to lesser derivation from the zero-error-curve - because the 12" tonearm does come closer to the theoretical ideal tangential.

Dear Peter: Your question IMHO has mre than one answer because there are mre than one factor involve.

If we take from the geometry point of view the 12" tonearm always will has advantage ( in theory ) over any other shorter tonearm. But unfortunately things are not so easy.

Looking to LOMC today cartridges the first " trouble " that we have is that the same cartridge, say a Titan i, will have a different resonance frequency with the SME 9" than with its " big brother ", this fact alone preclude a fair comparison ( and I'm not saying that the Titan is the best match for the tonearm, I take it only like an example. ) because that difference in the resonance frequency has its own " sound signature ".

Other subject that Dertonarm already point out: +++ the further away the cartridge is, the higher its influence on the mechanic resonance behaviour of the tonearm. +++++

and in my experience not only for the tonearm torsion resistance factor but depending on the tonearm build material, a 9" arm wand has a different " sound signature " than a 12" arm wand .

In the last three years that Guillermo and I been in our self tonearm designs we made ( and still do it. ) several and different tests and one of them was to have a shoot-out with the same cartridge, different ( same build material ) length on the arm wands, very near resonance frequencies between them ( due that we use different headshell weights ).
We do it with 9", 10", 11", 12" arm wands and we find that with the 9" is a clear overall advantage ( what we can hear )but betwen 10" and 12" seems to me that exist a " threshold "/land where it is extremly dificult to discern if there is a 12" advantage in the sound reproduction quality due to the stand alone length factor.
Our findings are very interesting because our propietary tonearm build material is almost neutral ( it does not have a " sound " ).

When the build material move away from " neutrality " then the differences are more " obvious ".

We are building a 14" and 16" other ones and we will see what happen, here the challenges are a little different.

I already posted on other thread that when you are in the audio item design ( any ) we learn a lot on the subject because we " live " every design day with the: why's, how's, where's and the like.
I hope to finish our tonearm project in the next three months.

What I learn/learned through the tonearm design help me to understand and learn too on the TT " behavior ", that's why in other thread I insist/push hard on TT build materials, this factor is definitive in tonearms and TTs quality performance more than any one can imagine.

Regards and enjoy the music.
Raul.