Field coil dava cartridge

@intactaudio 

Since you are one of the few here who interested in science and empirical measurement here is an interesting comment from Bruce Thigpen, designer of the ET2 linear tracker, whom has a degree in physics and audio engineering -

   The untold parameter of a pivoted tonearm: To minimize tracking
error, pivoted tonearms were lengthened with a bend in the wand, or by
mounting the stylus at an angle in the headshell. The frictional force
of the stylus in the groove wants to straighten out the bend or crawl up
the records inner groove wall. When using anti skating with a pivoted
tonearm to prevent inner groove wear, regardless of mass, pivoted
tonearms bend the stylus with an opposite side load force of between .1
and .2 grams per gram of tracking force, the tonearm shaft is being
twisted outward (as viewed from above) with this static load which goes
through the stylus suspension, but the percentage of creep on the inner
wall of the record groove actually varies with the passage loudness or %
groove modulation. So you are constantly bending the stylus while only
marginally solving the problem.

     With the ET-2 the side loads to accelerate the tonearm at .55hz
(33/13 RPM) are less than half of those values for an eccentricity of
.0312 inches (1/32 inch) and are a linear function of record
eccentricity. The cartridge cantilever suspension sees much lower loads.

     So as you add mass, this side load value of the ET-2 goes up
linearly, but is always less than using any pivoted tonearm with anti
skating.

    I hope this helps  - brucet

@mikelavigne 

You should read Bruce Thigpens comments above - as it relates to your CS Port linear tracking arm. Also I would recommend reading the ET2 manual on Bruces site - it has excellent information and testing data on linear trackers.

@mikelavigne 

constant minor side load is not as big a deal as sudden heavy side load.

True

linear trackers do also require precise set-up or they can put much more stress on the stylus at the point of initial contact with the groove....getting arm started; than a pivoted arm which swings free. 

Thats not necessarily correct - depends on inertia, not mass, and bear in mind a 12gm cartridge at the end of a 12" arm has significantly more inertia than the same cartridge at the end of a 7" linear arm. The effective mass and inertia on my FR64S are significantly higher than my ET2 for example. I find the ET2 linear tracker easier to set up accurately in fact - parallax error is much less likely on a linear tracker with an appropriate jig- than with a pivoted arm. Overhang is set with a very finely scribed line - much finer than a "hole" or thick dot on a typical protractor.

i also switched from the Rockport to the pivoted Durand Talea back in the day and overall preferred it at the time. now i own three pivoted arms (2--10.5" and 1-12") and they do their job in an exemplary manor too. more than one way to skin the cat and it’s all a matter of execution, not dogma. 

Yes I agree - I used to be a top end distributor at the peak of analogue - there is no perfect arm, linear tracker, gimbal, unipivot, knife edge - they all have pros and cons. I keep multiple arms of all types in rotation. More important is the quality and execution of the actual design and the synergy with cartridge.

Arm/cartridge synergy is a lost art now, as most brick and mortar shops simply don't carry the stock for customers to assess various combinations of cartridge and arm - in fact most sell top end cartridges or arms to order now - no opportunity for audition - sad fact.

@dover , It is difficult to achieve with three eyes. Bruce Thigpen needs more study in the area of suspension and mass loading. The groove loading at the horizontal resonance frequency of any air bearing arm is horrendous and clearly audible as a pitch irregularity which may well be why Mike Lavigne seems to prefer pivoted arms. I have to agree that negating skating entirely is the biggest advantage of straight arms. I think the best approach to that problem would be the Reed 5T or the Schroder LT. I also have to admit that the magnetic antiskating systems of some arms is superior to other methods. 

@intactaudio , @rauliruegas  is absolutely right. Our ears are very sensitive to amplitude changes but could never pick up a change in distortion of 0.1%. Humans are entirely incapable quantifying what they hear. More than likely whatever they think looks better, sounds better. 12" arm are just another form of penis envy. They come from an era when radio stations played 16" records and should have died with it.