Eminent Technology ET-2 Tonearm Owners

I have used an ET-2 since they first came out. It is now mounted on a TNT of early vintage (MK I, II??) which still has the spring suspension. I am about to convert it to the paddle ball suspension as soon as I can find some paddle balls and make up a few parts.

I recently plumbed it into my shop compressor so my tone arm is now driven by a 5hp compressor with a 50 gallon tank. I am running about 15psi but keep seeing 19psi as the sweet spot but I can't tell any difference. What is magical about 19psi?

On weight placement: whether you want the weights close to the arm tube or far away depends on the cartridge compliance. Bruce has a pretty good write up in the manual which is available on the ET website.

In fact, the best bass response and stability that I have achieved is with the weights about as far from the spindle as the cartridge is (in the opposite direction, of course).
More to come

Hi Frogman

Are we to take your words literally ? The cartridge is about 7 inches from the spindle ? Have you come up with ET 3.0, a longer I beam that I have only been thinking about, or are you talking about removing enough lead and having your weights positioned at number 6 on the I beam ?

Hi Apbiii - you said

“I am running about 15psi but keep seeing 19psi as the sweet spot but I can't tell any difference. What is magical about 19psi?”

Why 19 PSI ?

In discussions with Bruce above 20psi the normal hose will blow off and another hose type would need to be affixed to the nozzle. This is a conservative number from Bruce. I have used 24 and it did not blow off. But the bottleneck is not the hose – its the ET2 spindle itself - with more than 20 psi coming out of the manifold holes, the ET2 spindle itself starts to resonate/vibrate. When this happens music information is lost – described maybe as “air”, “space” and harmonics. Others can chime in with better words maybe ?

So 19psi is used as a number to indicate a threshold give or take a couple PSI. All our system /rooms are different. We will all therefore get varying results. Also the bigger factor IMO is the type of pump /air supply you are using, how clean, dry and stable your air delivery is and most important the condition of your actual tonearm manifold and air ports. I went from the original pump, to a MEDO AC110, to a shop compressor/surge tank, to the Medical pump I now use. Is your pump located in an area that has a similar temperature / humidity as the room your ET arm is in ? This is crucial IMO. Some owners I have talked to have kept these pumps in the garage - during winter or summer with 98 per cent humidity outside.

I have designed my setup so that a second ET2 regulator/filter is on the wall next to the ET2 arm.

Portable ET Regulator

The device normally rests in its holder which can be seen in the picture. I can and have taken this second regulator off the holder and kept it in my lap as the music is playing. I then turn the black valve both ways to instantly increase and decrease the air flow to the arm and listen to the effects.

There are also reports as Apbiii says where others have seen and read about these PSI numbers. In the past I have emailed with Arthur Salvatore and his members have confirmed 19 psi. With Arthur you can read about it at highendaudio.com and do a search on the ET2 arm.

At Audiogon – here are a couple of links that pertain to Dertonarm's ET2 testing.

ET2 PSI Link 1

ET2 PSI Link 2

Daniel if you see this please chime in as well with your extensive experience. We are all sponges here.

The truly great thing about this ET2 tonearm and this thread IMO is that all the opinions and recommendations that we are about to hear about can be experimented with very easily by each of us in our own systems. Whether we are talking about lowering or raising the PSI, or adding or removing lead weights and or changing their postioning. We are all talking apples to apples. I have this pent up feeling like I am at a place here where all of us are going to truly benefit immensely from discussions. New and experienced ET2 owners.

None of us are smarter than the whole of us here ?

Unless Frogman or someone else has come up with ET 3.0 ?

Cheers

Thanks Ct, I seem to remember reading in past about the hose/ coupling limitation. I have read the comments and discussion on Salvatore's site and found them interesting.

I scanned the threads you linked and did not find anything about ET-2 or pressure. Perhaps I didn't look close enough.

I don't have my setup plumbed in a way that allows me to adjust it from the listening position but I should probably do that. From what I can tell so far I think at 19psi things seem to go a little dead but there seems to be a nice spot where things open up a bit at about 16psi.

I agree that filtration is an important part of the system and while my compressor is located a bit far away in a different environment I probably have more dedicated to filtration and drying than most as I also use the compressor for spraying finish so I have more traps and driers than most. I also have a regulator at the compressor for the turntable line and another filter and regulator at the turntable. The regulator at the turntable is a low pressure large diaphragm unit which may help a bit. I do not have a surge tank at the table however.

Also here in SoCal there is probably less difference between the indoor and outdoor environment than in many parts of the world.

HAVE A LOOK AT THIS

Hi Apbiii – I would much rather be where you are in S. Cal. – it is 3 degrees Celsius here right now about 37 degrees F. :^(

In those previous links see Detonearm’s comments in the threads. In the second link is the turntable with air supply that was running an Air Tangent and ET2.

A picture is worth a thousand words. If there is anyone anywhere that has a picture of their setup they want to share but can't post for whatever reason - please send me an email. I have no problem creating a special ET2 section in my virtual system page so others can see your setup. I will keep it anonymous.

Cheers