Are linear tracking arms better than pivoted arms?

"Air bearings don't work" is quite a generalization. While I have only compared my Trans-Fi Pro to Graham 1.5tc & SME IV, I have no doubt that the Pro handily surpasses both of these pivot arms. To AtmaSphere's point, the Pro operates by design on low air pressure. A high-pressure bearing may propagate increased turbulence and vibration. This theoretical disadvantage may in turn off-set any theoretical advantage in tracking. Of course it is all about execution.

The Trans-Fi also allows shortening of arm wand length down to 1". While one can debate the theoretical advantage of a short wand, IME the audible improvement is easily detected down to the last 1/4" of adjustment. While a short wand may be considered an ancillary feature of a linear design, this feature is of great sonic significance and is obviously unavailable in a pivot arm.

It may be interesting to factor in an arm's versatility with respect to navigating anomalous off-center and warped records. However at SOTA the question is always about the best of all possible worlds. It is therefore reasonable to ask which design is better assuming a physically "perfect" record? In any case for this crowd a second pivot arm like a 4-wheel drive vehicle is probably within reach to handle the occasional blizzard. A relatively small percentage of my LPs are flawed w/r to warpage or eccentricity. Assuming a decent biscuit, I am won over by the relatively superior tangency of the linear arm and the low-resonance achievable with a very short wand as available in certain linear designs. With a low-resonance short wand(as distinguished from degree of rigidity) all bets are off. Could anyone who has used a 1"-2" wand comment on their experience?

Frogman, Your experience with ET2 surpassing SME V mirrors mine with Trans-Fi Pro vs. SME IV. As regards stylus deflection, when a linear air arm is used with a high-compliance cartridge, rather than shoot for perfect level I position the manifold so as to eliminate bias in stylus deflection during play as viewed through a magnifier. It might be that in this position the manifold is actually at a miniscule downward tilt toward the spindle, allowing gravity to work in ones favor and relieve torque on the stylus.

Agree with Samujohn and would extend his point by suggesting that ease of use and repeatability of results is an important consideration. In this regard (some) linear arms are a piece of cake relative to pivot arms. Perhaps any arm over $5K should come with a boxed homunculus to set it up.

I suppose a linear tonearm with a very short wand will have lower effective vertical mass than any pivot arm. Such a linear arm may place less stress on cartridge suspension relative to a pivot arm. The horizontal mass of a linear arm will always be greater than a pivot arm. However the friction/stiction of an air bearing is less than a pivot. This advantage might at least partial off-set the disadvantage of relatively greater horizontal mass.

Can anyone comment on these linked variables of vertical mass, horizontal mass, and friction as they collectively bear on cartridge wear, or for that matter, on sonic performance? Is there a threshold of low horizontal mass on an air bearing arm, beneath which stylus wear becomes an irrelevancy? For example, Trans-Fi has horizontal mass on order of 85gm.

So many variables and so little time.

Nilthepill, interesting points. In the horizontal a linear air bearing design has the advantage of zero static or dynamic friction. Moreover, assuming good eccentricity of LP, within certain limits the higher lateral mass of a linear arm could actually be an advantage, insofar as an inertial mass with constant momentum toward spindle would tend to reduce centripital force required to advance stylus.

Dertonearm, if I understand you consider a short arm to be the Achille's heel. I can only offer anecdotally that the shorter I adjust my tonearm the better it sounds. I can think of no explanation other than that improved resonance control of shorter arm is of greater importance than maintaining absolute VTA. Designers of top pivot arms obviously give much thought to controlling vibration with particularly elegant arm tube compositions. But it is remarkable how many long pivot arms appear to be casually designed in this respect.(Based on appearance I would include Thales in this second group. I would also include any arm with a detachable headshell.) But all things being equal regarding arm tube composition, a short arm should win at least with respect to vibration control.

Taken from another angle, is it conceivable that micro-variations in VTA(which long pivot arms also suffer albeit to a lesser extent), are any more detrimental than out-of-tangency tracking errors with pivot arms?

Finally, what pivot arm approaches a linear arm in clean portrayal of inner grooves?

Too bad the thread returns to generalizations & celebration of received wisdom. Mechanics is a system of complex variables. While the idea of an absolutely rigid bearing is comforting, in actual use the performance of a long lever arm is the sum of many forces including its own rigidity & resonant behavior independent of the bearing. In this regard a short arm surpasses a long one. As regards the low effective vertical mass and long travel of a short linear arm, anyone who has set up a suspension for motocross knows that a properly set up long-travel suspension is consistent with stability in tracking bumps. While yaw in some air bearing designs may cause errors in tangency, solutions to the problem are not inconceivable. For example in Ladegaard/Trans-Fi design, the mating surface of the slider is a wing of large 14 sq. in. surface area, whose long parallelism with air manifold enforces minimal yaw--together with minimal turbulence attendant with low air pressure.

This is not to suggest that this arm is the last word in design. Doubtless each type has strengths and weaknesses of theory and operation. Perhaps it is more interesting to consider the strengths and weaknesses of specific implementations than of abstractions. For example, a P2 may be nice, but I believe there are around six mating solder/mechanical joints in signal path through arm wand. Sacrebleu!

My minor revelation about the relativity in so much of this occured at a 2CH show while eaves-dropping on elevator conversation between four print magazine reviewers. They were exhanging preferences about various rooms. Each one had a different preference, none of which jibed with my own perceptions. One reviewer who liked the sound of what I considered a particularly mediocre and expensive room, had a published review the following month of that room's manufacturer. To thine self be true, particularly at today's prices.