Eminent Technology ET-2 Tonearm Owners



Where are you? What mods have you done ?

I have been using these ET2's for over 9 years now.
I am still figuring them out and learning from them. They can be modified in so many ways. Bruce Thigpen laid down the GENIUS behind this tonearm over 20 years ago. Some of you have owned them for over 20 years !

Tell us your secrets.

New owners – what questions do you have ?

We may even be able to coax Bruce to post here. :^)

There are so many modifications that can be done.

Dressing of the wire with this arm is critical to get optimum sonics along with proper counterweight setup.

Let me start it off.

Please tell us what you have found to be the best wire for the ET-2 tonearm ? One that is pliable/doesn’t crink or curl. Whats the best way of dressing it so it doesn’t impact the arm. Through the spindle - Over the manifold - Below manifold ? What have you come up with ?
ct0517
Thanks for the captivating infos!
- Although I agree on the idea of eliminating turbulence - isn't damping it not also introducing an additional flow resistance which will upset the  "balance" of implicite air flow resistances from air feed via calibrated air beaing openings to bearings air film? Personally I'd be very (self-) critical when changing this, I like to be double on the safe side about changing such crucial areas (at least with my limited understanding of air bearings).
In fact I'd contact Bruce about his thoughts regarding keeping the correct pressure on the distributed points/air openings when introducing additional flow resistance.

- raising the arm bearing: I meant lifting the back of the arm, and correcting with a 20 degree wood wedge between arm and cartridge (the wedge pointing to the front of the arm),

Pegasus

My techno-intuitive thought on this is:
- The lower the resonance of the i-beam, the wider the frequency range over which the bearing/cartridge resonance can be controlled by it.
- the higher the resonance, the closer together both resonances and the more resonant interaction instead of control.

Does Bruce have the model? Or should I ask my more MATLAB-experienced son?

Pegasus
The model for the original I Beam was in part influenced by business priorities. We know this. This limitation is no longer there.  

Why don't you send your theory and questions to Bruce direct and let us know what he says ?

brucet (at) eminent-tech (dot) com

I am interested in your, John and others impressions of Bruce' Long I Beam.

Harry and I seem to be in sync.
Also, still am interested in seeing pictures of your dual path wiring setup.

Cheers Chris

@pegasus 
I agree, there is likely to be a small reduction in air pressure entering the  capillaries due deltaP across the wool and filter paper. Easily sorted by increasing the input pressure slightly.  The arm can be operated with and without the wool/paper to test its efficacy.
Much has been written in this thread  about the need for a stable air supply. It seems that the ET is very sensitive to any perturbations in the air stream. This design is simply taking this trait and seeking to ameliorate it further. Look inside the manifold at the small hole which connects the air supply to the manifold cavity. Air entering thru this hole jets across the small gap and hits the sleeve then circulates around the boundary between the manifold ID and the sleeve OD. This design change is an effort to deliver smooth air to all of the capillaries. It may not be of benefit, but I intend to find out.

Cheers 
Bruce's second run, long I-Beam delivered yesterday.  Much better fit for the weight clamp.  Sounding good. 
Cheers

Gentlemen,
I recently picked up a Van den Hul MC One Special.  Specs say static compliance is 28 micron/mN.  I don't have a clue what this means in terms of high, low or medium compliance.  Can some of you with a better engineering/physics background than I tell me which of Bruce's arm wands would be best suited to this cartridge.
Thanks,
Harry