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
Hello Raul - Feliz año nuevo and welcome to the thread.
If I may make some comments to your post.

Rauliruegas
One critical subject in the sound generated by any subwoofer is that we at home need enough cubic area for the bass soundwave can be in real way developed, if that cubic area does not exist any one can't " hear "/ feel a 5 hz soundwave. We need " hundred of m. to those very low bass sounwafes really be formed.


Yes, I agree you can't defy physics when it comes to bass especially when someone is making a Subwoofer inside a BOX (enclosure) and placing it in a larger box "the room". One of the latest audiophile darlings.

The Gotham by JL Audio

reproduces 19hz - 200hz (+-) 3db
Dimensions* (H x W x D):
34.13 in. x 21.50 in. x 24.00 in.
867 mm x 546 mm x 610 mm
360 lbs. (163 kg)
$12,000 plus $3500 for the crossover. US dollars.

Now in regards to this ET Rotary Subwoofer - it is thinking "outside of the box" and it is designed to take over where that JL Audio Gotham stops producing below 20hz. It uses that "extra room in a persons house" meaning , the basement, the attic, side room that the rotary woofer gets installed in - the room, space itself becomes the BOX - the infinite baffle ....the sealed enclosure.....

Rauliruegas
Yes the ET unit is something really different of what we normal mortal audiophiles know

So who is the customer for this? This rotary woofer is now being used in theme park attractions, concert venues, professional audio applications and research projects. But I think there are also possible clients for this product right here at Audiogon. Any potential customer for a start would need to have $12,000 US dollars for the Rotary Woofer which is similar to the JL Audio Gotham price. But from there an additional $8k -$12k for the design and installation. So approx $20k - $25K US dollars total which includes crossover and external amp. And of course this person (client) has a house with the space available for the installation of the Rotary Woofer to create this infinite baffle.

For this, the person gets to hear and feel "the 11hz hertz fundamental frequency from a helicopter rotor, the low frequency rumble of wind, the space of a concert hall or infrasonic information contained in an explosion." taken from the website.

Well this client is not me.
But let us just imagine; this "guy" male customer (no woman would do such a thing right? ) but .......imagine this guys wife, spouse, better half coming home to see the inside walls of their beloved home doing this.

http://www.rotarywoofer.com/africa%20photos/Africa%20Video%20Snapshots/Kombi%20Roof.gif

the above is from the Africa segment linked earlier. I got a good laugh - the video shows outside the van containing the Rotary Woofer working inside the van to attract the Elephants.

And from that link's description.

"With the rotary woofer playing a thunderstorm recording, the elephants all stopped eating and turned toward the camper van."


Cheers

My 21 year old son sent me a couple links today. I think inspired by his girlfriend.....     
I started laughing when I opened them up and I thought for a moment, maybe there is some hope for him ?

had to post.

http://imcedb.com/images/1/12/Indecent_stereo.png


http://imcedb.com/images/1/1c/Indecent_turntable.png


Indecent Proposal - Robert Redford - TNT turntable and ET 2.0

My son always liked my old TNT - told me it looked like a tarantula spider.
Black is beautiful.

When Bruce told me he was going to be making parts in aluminum I thought for a second maybe he was about to add some bling to the ET 2 tonearm in the form of shiny aluminum. But he stayed true to his low key self with the blacked out aluminum mounting plate.    

ET 2 owners - notice the correct placement of weights for bass in the first link..

Anyone know what the cartridge is in the second link.....a Benz ?


Happy Listening
Dear ct0517: Yes, I remember the first time that I saw that very good picture and was my wife who took my attention about.

Obviously that tha beautiful house is a house where the owner likes music and know what this means in a home audio system ( I'm talking not of RR but the real owner. ).

IMHO, the ET tonearm is today an icon/sign in the audio history.

Regards and enjoy the music,
R.
Hi All
I have just finished testing a precision pressure regulator in the air supply for the arm.
I replaced a Norgren B07-201-A1KG reg with a Norgren 11-818-101
Findings in my rig...,

Was there an improvement? Yes. Things were a little clearer, more three dimensional and impactful.
A big change? No, but worthwhile.
All comparative testing was done when the compressor had cycled off, drawing air from the reservoir only.
The old reg has a built in filter/water seperator the new reg doesn't, so a seperate filter/ seperator was also installed before the new reg. So technically two things were changed.
Did this have an impact on the results?
Maybe 
Whatever, the new configuration is staying firmly in place.
The bleed off needle valves before and after the reg, that I posted some time ago, were retained and their beneficial impact confirmed.
It shows all over again that the arm is very sensitive to the quality of the air supply. 

Cheers 




RichardKrebs
It shows all over again that the arm is very sensitive to the quality of the air supply.


Richard - obvious agreement from me. I got sidetracked for a number of years (elapsed time) in my Audiophile phase PUMP journeys. 
Where does one stop ? It can be addicting. I did learn a lot about how different pump technologies work though.

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I think it is worth noting for newer readers, a couple important thread quotes from Bruce on Air Supply and Setting Manifold PSI Values.  

1) Air Supply (Quality - PSI and Mositure/Dirt)  

Bruce Thigpen
More than air pressure, the air supply will change the sound of the tonearm. if it is bad, allowing pressure pulsations to enter the manifold. Increasing pressure slightly and a big enough surge tank are the best things that could be added to the tonearm in terms of performance.

The key words to me from Bruce is increase pressure slightly, and it implies one knows what PSI your ET2 manifold was built for. If someone buys an ET2 on the used market we have discussed here how to find out the PSI/Bar it was designed for. As a guideline if a regular manifold - 3 psi. If a High Pressure manifold 8-10 psi unless it was a Custom Build. Once consistent PSI is achieved (think pulsations), the big other factor is moisture and dirt.

What helped me understand how important this moisture and dirt were, was to think about air brush painting and what happens if dirt/moisture get in the air line for the person doing the spraying.  Now I don't air brush myself but there are many air brush painting forums to get an understanding.  

For me personally. 
My Timeter pump is designed for keeping people/patients comfortable. It therefore has controls that allow me to vary the moisture being sent out as it has an integral drying system. The pump is affected by humidity and going from very dry winter air, to humid spring/summer air forces me to make pump adjustments to the level of drying.

I have found in my room on a few occasions during the season change from winter to spring (going dry to humid)  I could have been listening to digital for a while, then switched to vinyl, the system itself is warmed up;  at times the vinyl sounded wrong. Almost how reproduced music in a room can sound with cold solid state gear if you know what I mean. When the music sounds like this, it makes me think of wires and the gear. Not the music at all. 

Going to the pump I notice the dryness level needle has dropped some so I need to crank up the dryness factor a bit on the pump. So the PSI was just fine but there was some moisture in the air line - it affected the sound. And this is moisture "vapor" that is hard to be trapped by filters. Again the air brush forums help to get an understanding of this. Our audio expectation is nice music we enjoy. Their expectation is the finish on their painted product. Its all visual. For those running with tanks of compressed air - don't forget to drain the water in the tank before using (bringing the tank to its PSI level). My Timeter Aridyne pump is tankless.

The fact of the matter is if you live in a hot, humid place (I wish I was there now) you will have more challenges with air supply than the guy in a drier, colder environment.  So many environmental factors can affect the sound that are never discussed on Audiophile forums. 

2) Setting the Manifold PSI on ET 2.0 and 2.5 for specific customer requirements.

In the past customers have had Bruce design the manifold PSI for their pump's specific requirements. This is discussed on the Eminent Technology website when one is looking to buy the tonearm, as the pump system is not supplied with tonearm when you purchase it.

Bruce Thigpen

The pressure drop across the set screws define the restoring force and part of the stiffness of the air bearing.

The tolerance between the Manifold Inner Diameter and the Spindle Outer Diameter determines the lifting pressure as a function of flow rate through the set screw. Without a restoring force or pressure drop across the set screw, the bearing will lock up, so you always need a higher air pressure in the manifold housing as compared to the pressure at the surface of the spindle.

The high pressure manifolds have a slightly tighter tolerance between the spindle and manifold, they also use a set screw with more plating to restrict the air flow around the threads to create the increased pressure drop (the difference between the pressure in the manifold housing and the pressure at the surface of the spindle).

It does not hurt to slide the spindle in the manifold bore without air, the resistance you feel may be the surface finish roughness on the hard coat anodizing as well as tolerance.

I hope this helps, thank you very much.

-brucet


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Fnding the ET2 Yellow Sticky Thread Posts.

Here's the ET2 thread Yellow Sticky for the setting of manifold PSI values

https://forum.audiogon.com/discussions/eminent-technology-et-2-tonearm-owners/post?highlight=et2%2By...

The new Audiogon system allows one to find the Yellow Sticky Posts on this ET2 thread easily now.

Just enter Yellow Sticky in the forums search field.