Eminent Technology ET-2 Tonearm Owners

Hello Pegasus

Two posts that imo generate very good thought. I need to first say that ever since this ET2 thread started I get a special feeling in my gut whenever a long term ET2 owner posts in this thread for the first time. Especially when it is his first post on audiogon. Remember how this thread started - "Where are you guys ?" IMO - anyone that has owned ET2(.5) for a significant period of time, has been through a huge RE:LEARNING process with their records and how to play them, especially if your main tonearm before was a pivot arm. So welcome to this thread which I now see is about to touch 1/2 million views soon. Who knew ?

When you say

The main signal is cut laterally, one can safely assume that if there are very low frequencies on an LP it is cut *laterally*. The main disturbance laterallyis off-center records (0.55 Hz).
The off-phase info is cut vertically. The off-phae low frequency part is not doing anything helpful in normal rooms, so usually the LF signal below ca. 100Hz is blended to mono.

The normal warp & rumble zone is usually quoted between 2 to 5Hz - it leads basically to vertical accelerations. If one assumes that there are no important signals to be traced below 20 Hz or even below 50Hz (because the big excursions involved in low freq. creates problems for the cutting head *and* the cartridge. And because even in big listening rooms it is difficult to reproduce phase differences in LF) one places the optimal *vertical* resonance frequency between 5 and 20, or more radically even below 5 and 50Hz.
-> Vertical optimum is around SQR(5x20)=10 Hz or even SQR(5x50)=21 Hz
(so long so good, so often heard).

Horizontally there is a main disturbance at 0.55Hz (33.333rpm/60"), maybe 0.75 Hz (45rpm/60"). But there is a good reason to extend extraction of musical information like ELF reverb etc. down to at least 5Hz - if possible. Cutting and manufacturing LPs has several modes of creating vertical disturbances but only one or two horizontal issues: Off-center records (which actually could and should be corrected) and horizontal bumps on the cutting lathe - rare (but I have one such record in thousands of LPs).
So there is a moderate, but constant excitation/acceleration on 0.55Hz (basically correctable) and a useful extended LF range down to 5Hz which leads
to an
-> optimal horizontal res. frequency of SQR(0.75 * 5) = 2 Hz

It is my understanding that bass below 100 hz is mono as well. Your comments make me curious whether you have been involved in the lp engineering/mastering side at all ?

Do you still own the ET1 ?

The decoupled counterweight of the ET 2 gives simply more freedom with problematic pairings of cartridge, arm and off-center records. Maybe, when it is not necessary, blocking the decoupling could have advantages sound-wise.

A profound thought that IMO can only come from a long time owner with direct experiences. Indeed the ET2(.5) can accept all cartridges I have thrown at them so far, From extreme high compliance Sonus Blue Gold to the XV1 although the 2.5 by design is happier with heavier MC's. The problem is learning how to use the counterweight/springs does take time and patience. I am past the swapping of cartridges stage and have now settled in and just love listening to my music.

BTW in my experience it is extremely important to have both the platter and arm *extremely* well levelled in the horizontal plane. Side-forces on the cartridge cantilever lead to plummy bass. Probably because a variable pull with varying tracking friction on a laterally deplaced cantilever gives dynamically varying side forces - which might energize the horizontal resonance. It sure is very audible. In my setup it is important to check regularly, floating the arm with two equal blobs of Blue-Tak on both sides of the arm, one at the backside of the arm, the other on the counterweight.

Agree, in fact Bruce should have shipped ET2 (.5) all out with a pack of Blue-Tak.

For me it is the audio wonder tweak. It holds, it dampens, it can even clean your stylus....

Cheers

CT0517 - For me it is the audio wonder tweak. It holds, it dampens, it can even clean your stylus....

Blue-Tak audiophile tip # 115.

Put a very small touch of Blue-Tak on your "audiophile" screwdriver tip. You know the one with the Cocobolo handle that is used to put the cartridges on and take them off. Presto ! you will never lose another screw in the carpet. Your wife will never hear you utter the words " Damn ! I just lost one of the screws, and now only have one like that one left ..they were a special one of kind pair buy from xxxx ".

To this very day I am too scared to vacuum in the immediate vicinity of my analog rig for fear of hearing tinkle, tinkle, tinkle, tinkle, in the vacuum cleaner dirt holder. Screws from years past.

I think there is a couple ET2 leaf springs down there too :^(

all the leafs are brown... the fall is coming.. :-)
Yes Blue-Tak is something to have around, and I use it (I'm swiss :-) on my jewelers screw driver - when I remember...

No, I wasn't in LP mastering / cutting, but I have a profound interest on the electronic & physics side of that hobby. I make recordings of concerts at our place, and did some recordings already in the 70's with a semi-pro JVC portable cassette-deck from my brother.
And I did a few Magnepan modifications for customers, and made new low-diffraction panels, and calculated all new crossovers for MG3 and MG 3.3s.

I had to trade in the ET1 for the ET2, so I don't own it anymore, contrary to the ET 2 it was slightly crude in set-up and detail solutions - but it worked very well.

My main messages about the arm (which I always loved) are as follows:
- If the bass is off, it's probably the set-up (side level or maybe a too softly springed counterweight stud).
- If I only touch the VTA adjustment a bit on *my* ET2 - the side-leveling is severely off. If it's not, I was lucky. To check is better than to believe...
- The "critical theory" against air bearing arms, and specially the ET2, stands IMO on very shaky feet, as I tried to show above. If there is a structural problem it might be the slight elasticity in some of the joints.
- subchassis turntables have two main problems with an air bearing arm:
- the lever mechanism of the shifting mass offsets the subchassis (-> increases sideforces)
- The needle drag problem, ie. the varying friction with tracking, potentially sets up rotational forces in the subchassis, with every arm. This leads to a slight instability in the subchassis and pitch uncertainties. But it also kicks air bearing arms in a different, very undesirable and quite audible way: Side-ways. (Much more audible than a radial tonearm, where the kick goes much more along the stable axis needle to arm bearing).
So one gets both problems - the bass instability and the pitch instability.
But it's still feasible and it can sound very good.
- In my book of experiences, every screw that creates a touch more grip than needed to keep a joint or a connection from gliding, introduces quite severe grades of transistor-feedback sound. I understand this as a necessary minimal torque, but every further bit of torque is like tuning the screw up, in the sense of a steel string. Tune these down & out, and they ceae to resonate. It is less storage of resonant energy. So my ET 2.5 runs with minimal torque on all screw connections. It sounds less artificial and more integrated to my ears.

My ET 2.5 sits now on a partially spring suspended Technics SL1210 with some modification on the electronics. With a very old, original AT OC7, which sounds very, very good here. I know, it shouldn't :-)

****So my ET 2.5 runs with minimal torque on all screw connections. It sounds less artificial and more integrated to my ears.****

Hah! Precisely my observation. Very good exchange, Chris and Pegasus; thank you.

Hi Frogman - as Pegasus said the leaves are turning, some brilliant colors. It marks the transition soon from summer cottaging up north to some serious music listening coming up to help me get through the winter.

Pegasus - From your last post you must have quite the space to be able to hold concerts. I miss my daughters daily piano solos while she is away most of the year at school. When you mention customers and repair, modifications to Magnepan, do you have an electronics business of some type?

Many good points - the "minimal torque" a key one that was discussed here early on and Frogman indeed stressed it initially. If I may share some experiences with this "minimal torque" and it directly relates to your comment;

If I only touch the VTA adjustment a bit on *my* ET2 - the side-leveling is severely off. If it's not, I was lucky. To check is better than to believe...

The coffee has not kicked in yet so pls excuse any rambling. If I really start going you know the coffee is starting to work.

My first ET2 over 10 years ago now that came on a VPI HW19 MKIV.

From my other tonearms in the past including Technics, SME, VPI's, Dynavector, FR64s, etc... they all come/came with a flat surface mount. They are relying on the partner table to be level. This is not good. Turntables are crude devices. Many plinths/armboards not level with the turning platter. The cartridge is always the end victim. The ET2(.5) as we know have a genius grommet 3 spike mount. They could be mounted on the Leaning Tower of Pisa if need be. However the spikes WILL dig in over time if the surface is not hard, which causes the Pillar of the arm to go out of level. I have seen people mount them directly on hardwood. Not good. The VPI tables came with an aluminum plate to prevent marring of acrylic. Never great IMO to add layers but there was no choice and business (selling the tables/tonearm combo at the time) meant it had to be done. The spikes can be shaved down to allow for removal of the plate and naked mounting on the acrylic. ET2's mounted naked on a hard surface are much better sounding to me. Multiple layering of armboard materials - UGH ! And then some put layers on their platters too...

sorry to ramble; ok that first table VPI HW19 MKIV / ET2 I got, the previous owner could not get the ET2 to work. Long story short it was set up bad and the pump was down 1/2 psi - could not complete the last grooves of a record. I got another pump, which allowed for whole lps to be played; the sound in its as is condition still trumped the VPI JMW 12 inch arm at the time. I used it for a while then decided to take it apart. I discovered the two vertical bolts that level the arm on the VTA pillar were tightened down so much by (previous owner/s and my short use to that time) that they had put two bolt indents in the base below. Imagine the stress put on by the bolts. This was truly the opposite of minimal torquing.

These Two Vertical Leveling bolts are an operational dilemma with the ET2. Owners set them up initially and everything seems fine. Then over time with cartridge changes, bumping or moving the table, room seasonal structural changes to wood beams, etc ... things go out of level a bit and the vertical bolts need small adjustments over time. Owners give the vertical bolts a touch of a turn here and there not realizing the bolts are already putting pressure down. They go away on holidays. Come back... more listening. There is no way one can remember how much torque is on those bolts. A little more adjusting here and there. This ends up stressing the plate below, and could deform it. You will never get the patented VTA to work ! So this is a mistake not in initial setup, but from an ongoing operation. A possible outcome if not observed and it is not covered in the manual. One person I know did not realize how much force he had placed on the plate below and he ended up actually cracking it.

How I solved this problem was easy (like some things in our lives) Simple awareness and a habit change. If a level adjustment is needed, take 30 seconds and undo the torque on each vertical bolt; then re-apply this "minimal torque" as required on each bolt, as if setting them for the first time. This takes 2 minutes total time to do. This is very important and has worked well for me.

If you have mounted the ET2 spikes on wood direct - you will never get the table/Et2 and the VTA to work properly as the spikes will dig in over time causing a shift with the different tensions used to get level initially. My two ET2(.5) are mounted naked on a solid brass billet pod with the SP10MKII, and on the Aluminum solid billet pod on the La Platine Granito Verdier (Mr. JC Verdier- RIP)

Both are bolted down to the plinths below. The VTA works the pillar stays level. Metal ET2 spikes on a metal armboard.

IMO - success with any analog rig regardless of the cost point comes from the setup and paying special attention to the details. One more detail - The one ET2 (.5) threaded mounting hole is filled with oil prior to inserting the bolt. If you are using a wood armboard do not put oil in it.