Eminent Technology ET-2 Tonearm Owners

Dgarretson - With this design the lowest possible air pressure that floats the bearing(about 1 psi)sounds best.

DG - I am curious - is the 1 psi the recommended manufacturer psi? How high a PSI have you experimented with and how were the sonics affected on the Transfi arm ?

thanks

Is there significant air coming from the manifold where the spindle enters and exits? You will feel the air coming out with your finger near both ends.

NONE DETECTABLE AT ~3PSI BUT DEFINITELY FEEL AIR ESCAPING AT EITHER END OF THE BEARING HOUSING AT 7+psi - MORE AS AIR PRESSURE IS INCREASED, BUT NO "KICKBACK" OF ARM AT END OF TRAVEL AS OTHERS HAVE REPORTED.

Dave - 7 psi is over twice what the stock ET2 design calls for. So your arm is indeed working well - imo.

Bruce offers two upgrade options unless things have changed.

You send him your stock ET2 manifold and spindle and he can do one of two things.

upgrades it to 1) an ET2 HP manifold model or 2) ET 2.5 with the bigger spindle.

Something to consider - he can also make the air plug inlet point up or down.

As Frogman, I look forward to your impressions of the HP manifold whether as a ET2 or ET2.5 HP model.

Cheers Chris

Chris, the manufacturer recommends lowering air pressure of Trans-Fi to the point that the needle skips backward a groove, then slightly increase pressure to restore tracking. The air pressure at this threshold depends on the weight of the selected wand and counterweights. One owner with a very light wand and counterweight set-up reports running below .25 psi. I'm currently using a heavier custom wand with dual front and rear counterweights and a CF sled that together "float" at around 1.25 psi.

Similar to what I gather is the case for ET, with the stylus resting on a stationary record, a rumbling through the speakers increases slightly with rising air pressure. This effect is never at a detectable level with music playing. However, at pressures approaching the threshold of mistracking the bass comes up and musical presence improves.

To clarify, I mean to say that at LOW pressures approaching the threshold of mistracking, the bass comes up and musical presence improves.

Been thinking about the "air escaping" issue. Seems to me that what has not been made clear enough is that there will be air escaping no matter what the pressure is. While it is obviously true that an air bearing will be optimized for a specific pressure range beyond which some of the mentioned issues concerning resonance may occur, we also know that dealing with resonance is a tricky issue and a bit of a black art which involves the rest of the system (specific cartridge and its resonance characteristics, and even things like how much torque one uses to tighten the adjustment bolts on the arm). Clearly, there will be a point when too much, or too little pressure, will be simply too much/little, but I believe that there is a fairly wide range beyond the "design ideal" which is "system" dependent and which, as always, is determined by what simply sounds best.

Someone explain to me how in a "captured air" bearing design air will NOT escape regardless of the pressure delivered to it. I think that when we talk about being able to hear it, it is simply that, the point at which it becomes audible; not that there is no air escaping prior to that point.