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 ?
128x128ct0517

I used to think that there is little that could really be learned and understood about an individual’s true sense of integrity and mettle from “conversations” on an Internet forum.  I mostly still feel that way; but, there are, in fact, times when those things become very obvious in spite of the vagueness of the medium.  
 

(Btw, love Bruce’s ET2 T-shirt 😊)

 

Dear frogman. I assume that you are thinking about my post about

’’callling names’’ which I try to explain with logical means as

confusion between NAMES and PREDICATES or between NAMES

and ADJCTIVES which TURN names which say nothing about its

bearer in something else. But can we call expresion ’’traitor’’ as ’’calling names’’

which I try to explain as an LOGICAL ERROR . Aka that NAMES

LACK predicative function. However adjectives which are modify

names can HURT. Inquisition was based on religious dogmas.

Removal from our post can be seen in the same way. Cartainly

so without any reasonable ARGUMENT. Calling names is not

about argumens but more like ’’straw man’’ . Making caricature

of your opponent and ’’kill him’’. Or accusing your opponent with

some ’’wrong doing’’. I am not aware to have done something wrong

to Chris. He should think about his reasons ’’against his origine’’.

@lewm 

 I am wondering why mounting a large weight close to the pivot point makes any difference as far as overcoming the air pressure and collapsing the air suspension , 

Because the air bearing carries the mass of the arm/cartridge/counterweight in total - If you have a larger counterweight that increases the total moving mass to above what the bearing has been designed for then it could collapse.

@nandric 
From what I have read and understood, the removal of the post has only to do with eliminating the bot-trigger word "me.t..." to save the discussion thread being flooded with spam. Using this abbreviation is "logical" and understandable in verbal communication but it triggers the spam button on web-based discussion platforms.
Removal of that post had IMO nothing to do with something personal against you.

 

@ct0517 & @lewm 
Using the same counterweight spring, to half the lever, ie. the distance of the counterweight from the pivot axis and to double the weight increases the resonance frequency of the counterweight-spring system (by SQR(2) methinks).
Ie. bass pulse / group delay aspects come into play too. With the decoupling the resonance system is more complex than without (nifty 4th order instead of 2nd order).

Increasing the weight of the assembly / counterweight increases the "weight stress" *and* the "leverage stress" on the air bearing. Optimally, in mid travel of the arm, the center of gravity of the whole arm should be centered in middle of the air bearing. (Something eg. the Kuzma, Air Tangent and adanalog arms are by design). A short i-beam / short lever severely shifts the center of gravity toward the end of the bearing and increases the leverage stress. Ie. the bearing works less stable.

@lewm

Lewm

I normally don’t contribute to this thread, because I do not own and have never owned an ET2 or 2.5. However, I concede that it is probably a great tonearm. But when you speak of Newton, keep in mind that the net force exerted by a small weight at the end of a long lever That is required to balance a cartridge at a specific VTF will be the same as the force generated when you use a larger weight mounted closer to the pivot or fulcrum. Therefore I am wondering why mounting a large weight close to the pivot point makes any difference as far as overcoming the air pressure and collapsing the air suspension , Assuming the same VTF is thereby achieved in both cases.

Lewm

Setting VTF on a pivot arm is two dimensional. With the ET 2, the mass is adjustable so you could call it a three dimensional setup. Did you know that the counterweights are decoupled by a spring, and that the cartridge itself only sees the vertical mass and not the horizontal mass ? The word "stressed" is a better word than "collapse" Many years ago I never did collapse it with extra DIY weights, but if I added even more weight who knows. The experiment was over before that.

Page 9 of the ET2 manual on design. Adjustable Effective Mass

The effective mass of the tonearm is adjustable, both vertically and horizontally. The arm has low-medium mass vertically and medium to high mass horizontally. Four counterweights allow the vertical / horizontal mass to be changed. For example; if the user decreases the amount of counterweights used, and moved this position back (higher scale number) the horizontal inertia of the tonearm would go down and the vertical inertia would go up.

You can download the ET2 manual here

http://www.eminent-tech.com/techsuppt.htm

If you read the first 10 pages of the manual and the tech section, I believe you will get a good understanding of the tonearm.