Eminent Technology ET-2 Tonearm Owners

Analogluvr
I believe we may be almost neighbours! I tried to email you but it bounced back.

Hi Analogluvr

I'm about an hour north of the GTA; but in summer about 3 hours north. You can reach me at bcpguy(at)bell(dot)net.

Summer activities are coming to a close. Cooler nights and sun coming down much earlier. Its crazy when fall starts the way I just slip into this madness of a hobby without even seeming to miss a beat. For those keeping score the modded Music Reference RM9 amp is still powering the main speakers. No rush to insert the monster Krell to compare. Just enjoying the music when I have been home - like now :^)

Mister Frogman

I always enjoy reading your personal accounts as a musician; especially those words that talk to the interfacing that is needed to make musicians gel together.

Cheers

Hi Pegasus

Pegasus
I use twisted thin Audio Consulting silver wires outside of the arm, fixed via two or three small double sided foam ahesive pads. The wires go in a light curve, with a vertical radius, L/R some cms separated, to 7cm behind the arm tube, in the middle of the travel path.

I assume Ct0517 will tell me that my VTA mechanism has a problem - but it was never overtightened or any thing like that, it has equal spacing around and moderate to low "clamp".

Per my comments to Styrk - Are you setting up the wiring after you have done the initial setup and level of the actual tonearm ? If not your wiring may be affecting the leveling as the air bearing spindle is so sensitive. There would therefore be an effect, even if a small one, on the VTA block alignment if you level with the wiring.

VTA issues - Some of us notice this, other don't and it is based IMO on the stylus and how much detail it churns up. If the cartridge is musical but not overly detailed, one may never need to touch the VTA and not notice anything. Other than that, without seeing it, it is hard to discuss. I would however also inspect the base and 3 leveling screws to ensure there is no movement whatsoever. Maybe things got moved and something came loose with the main bolt. (especially into wood) This last comment is really for other newer ET2 owners. It's obvious to me from your posts your attention to detail is excellent. . Also never seen a 1210 with a wood base. Last option I can think of being a factory defect

Pegasus
Ie. with moderate to low compliance cartridges the counterweight decoupling introduces a new (sonic) compromise instead of solving a problem. But to really hear the advantage of a rigid counterweight, one has to do a bit more fiddling with the ET2 counterweight fixing than just using BluTak to bypass the spring (which I usually did).
For high compliance - I assume - it's ingenious.

This makes sense as the ET2 was introduced when high compliance MM were in their heyday. For moderate to low compliance think of a Double and Triple leaf spring. This was discussed earlier in the thread. Have Bruce send you five loose leaf springs and two I beams. This will allow you to make up one Double and one Triple I Beam. They cost only a few dollars. I use a double leaf spring mainly. I consider using different leaf springs part of an advanced ET2 setup and will let you tune your setup better. NO Professional Reviewers ever got this far with setup. Well I should not say this right ? OK - Point me to a review if it happened and I will acknowledge it.

Pegasus - I would be interested in knowing where you position the lead weights and how many on the I Beam. This would tell me more about your audio preferences than any other aspect of the ET2.

Pegasus
BTW I use a pressurized air bottle (rental system in Switzerland) as air supply at the moment.

????

8^0

Hi Chris (?) the compressed air bottle is a 200 atmospheres 60 liter steel tank. It provides "air DC" (to my arm & head) :-)

Wires: the Audio Consulting wires are twisted single strand 0.15mm silver wires with thin isolation. I dress them carefully (two L/R separated looms in a circle of almost 245 degree with ca. > 15cm diameter) going up from the arm in 90 degree to ca. 4cm above & behind the arm, slowly turning > 200 degree and back to vertically down. I measured the forces applied by the elasticity and weight of a single winding, it's around 0.05 gm. This is audible - if one does not correct for it. But I tune the downforce by ear anyway. The forces are low, and less in the horizontal plane. The end effect is what the arm does: It still skates off very slowly outside the middle 5cm to the inner and outer grooves.
The wiring works actually very well (far better than the original wiring), and I prefer to keep the wires twisted for hum compensation. Some time I used 0.07mm single strand copper wires, the applied slightly less force but sounded IMO worse.

Did you really check for absolute levelness after changing the VTA position, finding *no* change in side balance?
The imprecision is shurely on a very low absolute level, but not low enough in my case. I found out the hard way, by ear that there was a problem.

Dover, thank you for the link to the MIT video. Very interesting, and I was particularly impressed by how their designs are guided by music theory. As I said before, the conceptual parallels between the audio hobby and music making are many.

the compressed air bottle is a 200 atmospheres 60 liter steel tank. It provides "air DC" (to my arm & head) :-)

hah hah - I like your sense of humor Pegasus.

Like wise when needed, I sneak some Arizona like air from my Timeter pump. It is after all located next to the treadmill. (But its on its own circuit - heh - heh)

Did you really check for absolute levelness after changing the VTA position, finding *no* change in side balance?
The imprecision is shurely on a very low absolute level, but not low enough in my case. I found out the hard way, by ear that there was a problem.

Firstly Pegasus if I put myself in your shoes based on this problem, if it is really bothering you there are three options that I can see.

1) As you have sensitive ears, try a properly set up double spring I Beam. As you know especially with heavier stiffer LOMC cartridges, the single leaf spring I beam can be taxed more and induces more horizontal movement with eccentric records. The stiffer double spring does not do as good a job of damping the spindle on eccentric records but is what you should be using with heavier lomc's. The manual does not discuss this. If there was an updated rewrite of it the single, double, triple spring I beams would be a chapter on their own - imo.

To play records on an ET2 with a single leaf spring an eccentric record must not have a runout of more than 1/8 inch (from the manual) . The stiffer double spring would make this number a little less - imo. take note.

2) Send your ET2 to Bruce to check it out. He will tell you if it is within spec/tolerances for the year it was built.

3) Switch cartridges to one that doesn't reveal your particular issue to your ears. This is after all about enjoying the music right ?

I can change VTA anytime and I again do a quick gravity test with the handy
BlueTac Pancake which makes the arm free float. No movement at VTF 0, we are good. That is my test. I have these Blue Tac pancakes for whichever cartridge is on there. you start small, add a little on top till the arm floats like a teeter totter with two same weight people on it. Do you remember the uneasy feeling of being on a Teeter Totter as a child, with someone your same weight; and holding the teeter totter in a balance ? Remember if the other guy jumped off quick and you hit the ground hard ? The gravity test is no different, same principle. But the ET 2 has the ingenious holding cue arm for when you take the Blue Tac weight off the lead weights.

I need to also qualify something and I have mentioned this before here.
My ET 2.5 is a more recent build 4 or 5 years? not sure now - a custom build by Bruce and the manifold/spindle has tighter tolerances than my HP 2.0.
Let me better explain this.
With the air off sliding the spindle in and out of the manifold is much stiffer on the 2.5 than the older 2.0.
My ET 2.0 is also a HPM (High Pressure Manifold) - but it will still play with only 7 or 8 psi. in fact it will play with over 30 psi and no air hissing is heard and the inlet air tube does not blow off. It is a custom build obviously and it was bought used. My newer 2.5 needs 19 psi no questions. So here we have another example of the way Bruce constructed and changed his tonearms differently either by the buyers request or just as time went on. We know for instance that Bruce went to the 2.5 to meet the demand of lower compliance MC's. that has been discussed here before.

So how old is your ET2 ?