Linear Tracking Turntables - Best??

Oilmanmojo  

The ET2 has adjustable effective mass as part of its design. As Analogluvr knows, experienced owners know to set it up for highest vertical inertia.
This is well documented in the Et2 manual (Page 9) and the ET2 thread.

fwiw from this thread's perspective and comments from Atmasphere.

His experiences with the ET2 are documented on AudioGon here.

https://forum.audiogon.com/discussions/are-linear-tracking-arms-better-than-pivoted-arms/post?postid...

Atmasphere
Later I had an ET but after eating a few cantilevers, I ditched it. Obviously I had the wrong cartridges in it; you could sit can watch the cantilever move back and forth as the arm tried to negotiate the LP. If you have ever seen the arm 'wobble' you know what I am talking about.

@Atmasphere

From my personal experiences, No, not wrong cartridges - just set up wrong. In this case it appears from your comments that it was 1) improper set up and 2) severely eccentric records.

Page 47 - ET2 manual.

If you like to play severely eccentric records, ones with run out greater than 1/8th of an inch, then we suggest you use a low mass pivoted arm

From a cartridge end I have gone as high as 50cms/dyne x 10-6 with no issues with proper setup on an ET2.

Air Bearing linear trackers will always have higher horizontal mass. I don't know one audiophile that plays severely eccentric records. I mean Audibly what's the use. Unless you want to carve out the hole a bit and use a center weight. That's getting pretty anal !  but maybe it's a special record. 

Happy Listening.

Atmasphere

All ET 2.0 and 2.5's are designed to work at a certain PSI.  Bruce tailored them to customer specs and he also offered lower and higher pressure models. They need to be run at the PSI as designed.
Now The problem. 

Many owners especially those in high humidity areas not using a water trap, have let moisture carrying minerals and other crap into the manifold allowing the capillaries to get partially clogged. This is when higher psi does indeed help a bit forcing more air through the manifold and the capillaries/partially clogged. Owners wrongly assume it sounds better because of higher PSI.   But its a band aid.  The fix - clean out the holes! .....and use at the designed PSI.

Many buy used ET2's and have never cleaned out the capillaries as shown in the manual.  They have never ever  taken them apart; and they have no idea what PSI they were designed for - like an ebay sale. We have discussed the procedure for how to determine the PSI that Bruce designed them for on the ET2 thread.

So one needs to filter out (pun not intended) and qualify what you read on the internet. The design also has a 19 psi limit -  if set up this way by Bruce in the first place. Like my 2.5. So if you read about someone using i.e  28 psi .......:^)   be leery.

Air Quality vs Air Volume Higher PSI. 
Don't confuse higher psi volume of air over the quality of the air delivery that is being delivered. If the ET 2.0  2.5 is operating properly it is the quality of air delivery from a better pump - not the higher psi that improves its sonics. This is proven by using two pumps, same psi differing in air flow quality only.

The ET2 tonearm more than any that I have owned or am aware of allows, invites mods.The envelope can be pushed as far as you want to go. But, first, you need to figure out how it works.  This takes time and patience and out of the box thinking since it is unique.  

Larryi
The air bearing "slop" issue has to do with not having physical contact between the arm and the structure of the rest of the table (arm base and plinth). Micro vibrations caused by the stylus tracing the groove don't have as effective a path to be dissipated elsewhere so the arm itself tends to shake.

LOL - Larryi - Hilarious stuff.... where do you guys come up with it :^)
You made me spit up some coffee...I guess I could use a new keyboard.
 
Well you made me do some digging on the ET2 thread. How do I remember this stuff, but I can't remember where I put my car keys !  

You may search Dover's post at this time point on the ET2 thread for more detailed info.

Dover's post on the ET2 thread. 03-05-2013 6:29pm

Martin Colloms did in a Hifi News review years ago ( 1985, I think ). He measured the resonances before and after the air bearing and compared them to ascertain how the air bearing dealt with such. Typically you would use an accelerometer placed on either the arm or bearing housing to measure these.
If my memory serves me well the resonance profile remained in tact, in other words even though the resonance is passing through air and rubber, it went through almost unhindered.

Some more research.

SLOP

verb
1.
(of a liquid) spill or flow over the edge of a container, typically as a result of careless handling.
"water slopped over the edge of the sink"
synonyms: spill, flow, overflow, run, slosh, splash
"water slopped over the edge"

2.
feed slops to (an animal, especially a pig).

noun

1.
waste water from a kitchen, bathroom, or chamber pot that has to be emptied by hand.
"sink slops"

2.
NORTH AMERICAN
sentimental language or material.

"country music is not all commercial slop"
*********************************************

Now, if I post the urban slop definition I will most likely be banned from this forum.  

Atmasphere - I bet there are a lot of owners that don’t check that!

Yeah. there are a couple things to check If buying a used ET2 with no history known.

First one needs to determine if it is a 2.0 or 2.5 model. The 2.0 came out during the MM heyday. The 2.5 has a wider diameter lower resonance spindle, more ideal for MC. Bruce isn’t/wasn’t big on labeling; they both say Eminent technology ET 2. An easy way to verify which is which; on the end cap that holds the I Beam/ Weights. If flush with spindle its a 2.5, and if it overlaps, it’s a 2.0. 90% of those that I see for sale are 20+ year old base ET 2.0’s. From reference to the ET2 thread over 2000 ET 2’s were sold.

One then needs to determine if it is a low or high pressure manifold. Bruce inscribed HPM on the actual high pressure manifolds. When it is taken apart to check the capillary holes this will be found. With the Air Bearing, it’s a very straight forward procedure for any DIY person to clean the capillaries. If one can change out the cartridge on your sink faucet you can do this procedure. By doing this you also gain knowledge on how it works. Clean capillaries out with isopropyl as discussed in the manual. Put back together, insert the filter/moisture trap in the line and you never have to worry about the capillaries again.

Then one can check for PSI design and the pumps.

The base original low pressure ET2’s were supplied with Takatsuki 3.5 psi pumps. Go forward 25 years and Ebay ET2’s are still being sold with - guess what...
The same pump ! LOL ....What does that tell you ? Two things actually.

1) Surprisingly the original one I still have one in a cabinet somewhere, still puts out about 3 psi when tested but I’m sure its performance in quality of air delivery is no longer the same.

2) It is easily bettered and the manual discusses how to upgrade it with a better pump. IMO This combo base ET2 with the Tak pump was more of a business case decision to sell the tonearm. The PUMP journey is a wonderful audiophile adventure on its own. My journey lastly years and taught me a lot about hydraulics. The quality of the air delivery accounts for over 50% IMO of the sonics story on a properly set up ET2 tonearm.

All reviews I have ever read on the tonearm, all for the ET 2.0, were glowing ones. But no professional review that I have read, ever demonstrated any of the advanced setup techniques, and knowledge that we discuss on the ET2 thread such as weights positioning, single, double, triple leaf springs to match up with the compliance of the cartridge, and single shot wiring bypassing the factory wiring setup; This was done (factory wire setup) IMO again as a business model, to enable the tonearm to work in a package with other manufacturers turntables. This base factory wiring setup is the main reason that most have problems with setup. The ET2 Air Bearing is way more SSS "sensitive", "slippery", "smoother" than other captured air bearings that I have seen/heard. Wiring setup affects performance directly. If one has problems leveling turntables and tonearms; well then there will be two main problems/challenges with setup. Some people have problems differentiating between the two.