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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
frogman
7,559 posts
 
Re "escaping air". Even with the HP bearing/manifold there will be air escaping from the ends of the bearing. In my case you hear it only when the arm is at either end of its "trajectory"; and certainly cannot be heard when music is playing. IOW, you hear the air when it escapes and then has either the rear end cap or front elbow to make contact with. In general, the sound of a small amount of air escaping is normal, subtle, and should not be surprising. Chris is correct about the issue of pressure at the pump vs that at the arm, but the Medo 0910 is conservatively rated and actually outputs closer to 30 psi, so achieving 17-19 at the arm should not be difficult. Dave, you will be very pleased with the HP manifold and Medo; it is not a subtle difference. Keep us posted.
dgarretson
2,618 posts
 
Air escaping from the bearing can cause subtler damage by modulating the arm wand and stylus. This may be a necessary evil in any air bearing design... Doubtless the effect can be mitigated by reducing air gap tolerance or with arm wand damping. I suspect that the Kumza Airline has a particularly close gap, as it is designed for higher pressure 60 psi operation. At CES I asked F. Kumza about this. He replied that as the technology is well proven in industrial instruments in microscopic applications, it should be good enough for audio.

Trans-Fi/Ladegaard is the only air tonearm that I know of that doesn't use a captured air bearing. Air escapes freely all around the bearing. With this design the lowest possible air pressure that floats the bearing(about 1 psi)sounds best. A different approach.
frogman
7,559 posts
 
****Doubtless the effect can be mitigated by reducing air gap tolerance****

That is precisely what the HP bearing/manifold does. Point well taken, however. I will say that after using the regular non-HP bearing with the "higher" pressure Wisa for a few years (before getting the HP) I experienced no damage traceable to this issue.

Re the "different approach":

The Forsell (which still sits in its boxes waiting) uses the low pressure/non-captured bearing approach. Will report when I get around to setting it up.
ct0517's avatar
ct0517 OP
2,041 posts
 
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
ct0517's avatar
ct0517 OP
2,041 posts
 
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
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