Eminent Technology ET-2 Tonearm Owners
Not seeing the forest for the trees. Sometimes the obvious is not so obvious. Both of my ET2 arms are currently mounted on pedestals/pods where the braided wires come down vertically at least 6 inches before they touch the plinth. I had experimented with the newer Cardas wire and it was causing some frustration in me this past year as I moved the arms around many times between pods, pedestals and full plinths. That Cardas wire just seemed to twist and curl, go into loops when braided and was not user friendly. Well from pictures and suggestions here I unbraided about 8 inches of the wire into separate strands starting where it exits the arm tube. Much better results. With each strand separated it no longer twists and curls into loops -it can be tugged at with little effect on the arm, when it is raised and balanced with the extra blue tac on the couhterweights making it delicate. Just passing this on. Cheers |
Hi Frogman, For direct couple counterweight, I am thinking of fabricating something similar to the Walker http://www.6moons.com/audioreviews/walker4/vtf%20and%20center%20gravity.jpg I think it is probably important to keep the total weight of this counterweight assemble close to that of the original design. Cheers! |
How much weight can the ET-2, ET-2.5 designs carry on the I Beam ? I hope that this will help to clear up ALOT of questions with some of you. It did for me. The high pressure manifolds are not all the same. The ET 2 and ET 2.5 high pressure manifolds were built based on customer specifications for the pumps they were planning on using. So there are different versions. The higher pressure versions of these will handle more PSI and will also handle more weight. How much weight ? On January 3rd - I posted this information from Bruce regarding adding more weight. Chris Adding weight in this direction causes an asymmetric load on the air bearing so there will be a point where the bearing may bottom at the end of play position. The other thing to consider is the suspension system of the turntable, you are adding moving mass, this weight moving laterally may cause the suspension to deflect and change the state of level of the tonearm. Increasing the horizontal inertia can cause increased rumble. As long as you understand these potential problems it does not hurt to experiment and have fun. Thanks brucet In Support of this. Here is an email trail from “today” to help as well. Understand that the ET-2 Design and the existing ET2.0 manual is based on the original design running at 3 – 3.5 psi from years ago On 1/17/2012 7:35 AM, wrote: Hi Bruce The ET-2 is provided with counterweights for 15 grams. The use of less weight with lighter cartridges as the manual discusses is preferred - and the goal is to keep the weight at the end of the IBeam (higher number). The manual says we can add more weights up to 20 grams. Is the 20 gram a threshold number where after that, the weight affects the arm in a negative way? What did your studies show will happen to the arm with more weight than 20 gms? Thank u. Chris -------------------------------- Chris, Use the minimum amount of weight far back on the beam meaning beyond scale number 4. The only limitation is air bearing binding at the extremes of travel due to the asymmetric load. If your air bearing will carry the load you can put any amount of weight on it. I hope this helps. brucet ---------------------------------- Thx Bruce - in your opinion does a higher air pressure 20 psi coming out of the manifold allow for more weight to be placed on the I Beam than say 6 psi. Does the higher 20 PSI support the air bearing better for more weight than say 6 PSI or does it have nothing to do with it. Chris ----------------------------------- Chris, Yes, higher pressure should allow you to carry more weight. – brucet REVELATION PART OF IT I then called Bruce. I found out that all these ET 2.5’s manifolds are designed based on the pumps that were to be used with them by the customers ordering them. They will not all do 20 psi at the arm. If you bought a new ET 2.5 the manifold has been built for the pump you are using or told Bruce you were going to use. If you bought it used what was the previous pressure the owner was using? If you don’t know there is an easy answer – bump up the pressure and listen to what happens. When does it hit the brick wall? It sounds like for some here it is 15 psi – 17 psi. For others 20 psi is not an issue and maybe beyond. My ET 2.5 manifold was designed for 20 + psi. How do I know? I had Bruce do the update from a ET 2.0 last year and told him I was running 20 psi on it and above. It still works at 10 and 15 psi but I can also go to 20 psi + with no issues and I now intend to try 25 -30 PSI with a different hose and see what happens. I hope this clears up questions. BTW – If it is not obvious from the Jan 3rd post Bruce does not know how much weight a high pressure spindle designed for 20 psi can carry. He did tell me definitely more than 20 gms. Too many factors involved including the turntable – like if is suspended, and other considerations …. This is why he says experiment and have fun. Cheers I hate these long posts - sorry for any errors. |
Ct0517, good info. What I would like to know is how to inspect a manifold to determine what pressure it's set up for. I would guess that things like the spindle/manifold clearances and capillary size would need to be measured. Did Bruce mention how to determine this? Maybe he could let us know the specs that he built the to for different pressures. |
