Eminent Technology ET-2 Tonearm Owners



Where are you? What mods have you done ?

I have been using these ET2's for over 9 years now.
I am still figuring them out and learning from them. They can be modified in so many ways. Bruce Thigpen laid down the GENIUS behind this tonearm over 20 years ago. Some of you have owned them for over 20 years !

Tell us your secrets.

New owners – what questions do you have ?

We may even be able to coax Bruce to post here. :^)

There are so many modifications that can be done.

Dressing of the wire with this arm is critical to get optimum sonics along with proper counterweight setup.

Let me start it off.

Please tell us what you have found to be the best wire for the ET-2 tonearm ? One that is pliable/doesn’t crink or curl. Whats the best way of dressing it so it doesn’t impact the arm. Through the spindle - Over the manifold - Below manifold ? What have you come up with ?
128x128ct0517
After a week in Australia for F1 racing, I checked this thread.

Surprised I was, that it continues: high horizontal/lateral mass wrecks cartridges (words to that effect), or at least Richardkrebs arm setup does (words to that effect).

It catalysed me, finally, to read Michael Fremer’s review of the Kuzma Air Line Tonearm.

I figured as Franc Kuzma uses significantly MORE horizontal mass than Richardkrebs with his low compliance cartridge, Mr Dover would implicitly conclude Kuzma doesn’t know what he’s about, selling a defective design.

Well, revelation: Michael Fremer says (after initial academic objections to the design)

“Ultra-black backgrounds; enormous, airy, startlingly stable soundstages; palpable images perfectly placed and sized; ear-popping harmonic, dynamic, and transient complexity—I could blather on about the Air Line's convincingly natural performance and brilliant overall balance.
I'd rather just get to the point: In every playback parameter I was able to delineate, the Kuzma Air Line's presentation was staggeringly better than that of any other arm I've auditioned—with the exception of the one included with the $70,000 Rockport System III Sirius.”

“With the addition of a damping trough, the Air Line could very well be the finest tonearm ever built.”

Mr Kuzma replies to MF

"A question of damping..."
A system will resonate only when disturbing forces appear at the resonance frequency. If there are no disturbing forces, then there are no problems. However, if a system is overdamped, then instead of one resonance, two smaller resonances occur, one below and one above the previous resonance, which can create further problems. There is, in fact, a level of effective damping on the Air Line tonearm. The cantilever suspension, and the air supply tube add damping. Our choice was for either too little or adequate damping; we chose the latter.

"Eccentric LPs and any deviation from absolute horizontality will create...problems..."
Horizontal disturbances of an eccentrically spinning record occur only at 0.55Hz or 0.75Hz (33rpm or 45rpm). This is well out of the Air Line tonearm's resonance in the horizontal plane, which is between 2 and 5Hz and does not cause problems tracking virtually all LPs. Plus, if one has a defective disc so poorly pressed or off-center that it might cause such problems, it is perhaps most prudent to simply not play it.”
(Sorry guys if these comments are already part of the thread).

After such a classy weekend I cann’t energise myself to provide a series of theoretically derived, professorial quotes.

It is self evident Franc Kuzma is the real deal, producing superlative product with inherent sonic performance at the far end of world class designs.

Suffice to say Franc Kuzma can be trusted to confidently illuminate the subject.

The same cannot be said of Mr Dover’s bombastic contentions.
Thekong.

Just for clarity. Will you be adding the fixed counter weight to the ET2.5 or the ET2?

You mentioned the ET2 in your latest post.

thanks
Hi Richard,

I will be using the ET2.5 in my test. My ET started out as a 2, which I later added the 2.5 bearing from Bruce.

I was asking whether replacing the lead counterweight with something else (brass/bronze ?), while still using the decoupled I-beam / leaf springs, would cause a big difference in the sound.
Thekong
Thanks for that

The advantage of lead is of course its high specific gravity, it is dense and self damps quite well.
Don't know the effect of other materials there.

This could be a new line of exploration. I look forward to your findings.
Thanks
Richardkrebs/John47

Quote from ET2 Manual – Bruce Thigpen

P29

It is desirable in most cases ( low to medium compliance cartridges 5x10 dynes/cm – 20x10 dynes/cm ) to use the minimum number of weights, far out on the cantilever stem. This decreases the horizontal inertia of the tonearm while increasing its vertical inertia.

This is the exact opposite of what Richardkrebs continues to advocate. Richardkrebs is advocating increasing the horizontal inertia for low compliance cartridges – the opposite of what Thigpen recommends.

Re the comments on the Kuzma

There is a lack of comprehension of what is claimed with the Kuzma.
Frank Kuzma is quoted as follows
Horizontal disturbances of an eccentrically spinning record occur only at 0.55Hz or 0.75Hz (33rpm or 45rpm). This is well out of the Air Line tonearm's resonance in the horizontal plane, which is between 2 and 5Hz and does not cause problems tracking virtually all LPs.
That is all he is saying.
Kuzma does NOT say the cartridge does not see this resonance, it simply means that it does not cause problems tracking. This is because if the resonance of 0.55hz were within the tonearm resonance range the two resonances could at worst sum and “double up” which could cause tracking problems.

I quote Bruce Thigpen
the cartridge will "see" .55Hz mounted in any tonearm, more so in one with higher horizontal inertia

I don't think Kuzma means the stylus does not deflect at all at .55Hz, that would defy physics

Note that Thigpen says that the 0.55hz is seen “more so” with higher horizontal inertia. I would suggest this is one of the contributing reasons for Thigpen recommending a lower horizontal mass for low compliance cartridges.

You continue to ignore Bruce Thigpens' recommendations based on the laws of physics and his extensive testing, because it would appear you do not grasp the physics and engineering principles involved. Unless you understand those principles then you are unable to understand what underpins Thigpens' and Kuzmas' comments and designs, and are speculating at best.