Eminent Technology ET-2 Tonearm Owners

Dover/Richard/Frogman and others trying the magnets.

Another short listening session today then I had to head out for the evening. My impressions are mixed now. Not sure what to think. I really feel with myself, when tweaking like this what I can hear can depend alot on my mood going in, and how the day went. This is why multiple sessions are required for me over time. I have added more magnet slivers (4) to each side. Will have a few more listening sessions this week.

Richard/Dover

I used to enjoy “shagging” fly balls during practice playing baseball when I was younger.
Cheers

I reached out to Bruce to get his opinion about the shims idea for the manifold. Look forward to his response and will post back what he says.
Cheers

I have finished testing Dover's mag configuration on my modified ET2, along with individual mags independantly at either end. This has been the most extensive test I have done with magnets, spanning 3 nights of listening. The results were consistent and largely the same for all mag configurations. Differences being the degree of change. I used both weak fridge magnets and what I believe to be strong neo magnets.
Test records were..
Corelli, Harmonia Mundi 7014, track 1
Oscar Peterson Trio, We get requests, Analogue productions V/V6-8606 track, You look good to me.
Saint-Saens, Respighi, Proprius 7857, track 3

The descriptions here are all referenced to no magnents, being the control example. All changes noted were minor but repeatable over the three nights and were present with both magnet strenghts.

With the magnets in this is what I heard....

Corelli. The harpsichord notes lost some of their attach. The spaces between the individual instruments of the orchestra was reduced with the sound stage being compressed laterally and front to back. The piece begins with a series of very short movements, each stopping abruptly allowing the sound to decay naturally into the hall. The tail of this decay was shortened.

Oscar Peterson. This track begins with a bowed bass followed by the piano and drums, it steadily builds to become quite loud by track end. The effect is dramatic. The bowed bass had less bite. Less slip stick of the bow on the strings. Ray Browns usual muttering as he plays is less apparent. Less space between instruments and smaller sound stage. The build up to the final notes was diminished.

Saint-Saens. The singer uses vibrato to good effect adding interest to this piece. This vibrato was rounded, smearing her voice. An aside is the airconditioning that can be heard on this track. It rumbles along beneath her voice. With the mags in place this becomes more of a low frequency hum. Sound stage and hall cues were diminished.

With all iterations, there was a fog added, this covered up low level detail. There was also a slight feeling of unease, a tension which by the third night had become annoying.

The greatest negative change was with the 4 strong magnets, becoming less of a problem as I reduced strength and number.

All of these differences were slight, but it is the litle bits that make this hobby of ours interesting.

For those of you who may be interested in adding mass. I would bring your attention to Morch's latest arm which uses massive weights to increase horizontal mass. On their web site it does not say what these weights are made out of, but brass or stainless steel would be reasonable asumptions. Extra weight like this would dwarf the 30 or so grams I have added to my ET.

An appology. Some of you have contacted me via my Technics upgrade web page krebsupgrade.com While I can see the mail, I cannot at this time open them or send replies. I will get it fixed asap.

Richardkrebs,

I have finished testing Dover's mag configuration on my modified ET2

For the record you have NOT tested my ( Dover's ) configuration at all.

You have only tested magnetic dampening in the context of your own reconfigured version of the ET2. Your added lead mass has pushed the operating parameters of your ET2 outside of the original design.

Your ET2 is set up completely differently to mine in that :
You have rigidly coupled the counterweight to the arm.
You have added lead mass to your bearing tube.
You have added lead mass to the headshell.
You have increased the horizontal mass significantly over the standard arm.

The configuration I use is:
Decoupled counterweight in the horizontal mode ( spring bypassed )
Lightened tonearm
Minimal magnetic dampening

The level of actual magnetic dampening I use is as follows :
Shure V15VMR - 1 cupboard door magnet under the bearing tube at counterweight end
Koetsu Black - 1 cupboard door magnet as above
Madrigal Carnegie Model One - 1 cupboard door magnet as above
Denon 103 Garrott ( Aluminium/Boron hybrid cantilever/Weinz Parabolic diamond ) - none

Yet again, and you seem to do this with monotonous regularity, you misrepresent statements and arguments in order to justify your own point of view.

For those of you who may be interested in adding mass. I would bring your attention to Morch's latest arm which uses massive weights to increase horizontal mass. On their web site it does not say what these weights are made out of, but brass or stainless steel would be reasonable asumptions. Extra weight like this would dwarf the 30 or so grams I have added to my ET.

Your argument is wrong. The Morch arm is a pivoted tonearm. The ET2 is an airbearing tangential arm. The Morch applies its mass at the rotational pivot point. You have added lead mass to your ET2 at 3 points - the headshell, the bearing tube and the counterweight.

One needs to understand the physics as it applies to Linear Dynamics versus Rotational Dynamics. The added mass under these different conditions will have quantitatively different outcomes. You don't appear to have considered this at all.

Furthermore, the Morch website confirms my earlier statement that added mass, magnetic dampening and fluid dampening are not the same yet you contend that they are. Morch state on their website that mass increases inertia and has no dampening properties as I explained to you earlier. Morch use silicon fluid to dampen the motion in addition the added mass weights, again, which only increase inertia.
Your earlier contention that added lead mass is the same as fluid or magnetic dampening is incorrect.

Again I caution readers that adding lead mass in the manner advocated by Richardkrebs could potentially lead to cartridge and record damage when playing most records which are eccentric.

Why ? Because the added lead mass is loading up the cantilever.

Dover please re read my opening sentence.

"I have finished testing Dover's mag configuration on my modified ET2"

This clearly states that my ET is modified as anyone reading this thread recently would know. My testing was done in that context. That fact is obvious. The Dover Mag dampening test was as you proposed to Chris and that he asked me to try. I also took the opportunity to revisit earlier versions with strong and weak magnets independantly each end.

I have not said that mass, mag dampening and fluid dampening are the same other than that they all resist motion and that this resistance increass with frequency.

The Morch adds what appears to be considerable mass at a radius out from the pivot point. In so doing they have made a flywheel. Lateral movement of the cantilever mounted on a pivoted arm tries to rotate the arm about this pivot point. This added mass, flywheel, serves to resist this rotation tending to keep the cartridge still, a desirable trait. As viewed by the cantilever this is no different to me adding mass in the linear plane to the ET. Adding too much mass would result in unwanted cantilever movement due to record hole out of center problems. We agree on this, as you say it would load up the cantilever, but Morch with their flywheel do not appear to have reached that point nor have I with my arm.