Eminent Technology ET-2 Tonearm Owners

Hi Chris,

Merry Christmas my friend!

I am a bit confused by the last statement above. If the cartridge’s generator is misaligned, I can easily see why listening will give a better result than setting azimuth using visual alignment tools, mirrors, etc. that use the cantilever orientation (or even worse the cartridge body) to try to roughly approximate true azimuth alignment. But, given the same misaligned generator scenario, why would using a test instrument (say a Fozgometer or an oscilloscope) that reads each channel’s signal output independently and also the output signal balance between both channels give an improper result?

Best to you Chris,
Dave

Hi Dave.

why would using a test instrument (say a Fozgometer or an oscilloscope) that reads each channel’s signal output independently and also the output signal balance between both channels give an improper result?

Sorry for any confusion.
It is my understanding that "some" good carts yielding very high levels of separation, are not necessarily Symetric. They are Asymetric. If you try to use an electrical device in this type of scenario to balance the channels, you will not set up the cart as it was intended to be setup from the factory. It will be an "improper result".

I got this information years ago in talking with Peter at Soundsmith who has retipped for me in the past (two - carts I had bought used), and one of my own - that I beheaded. *^(

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Now Mike just happens to be using a Soundsmith cart and a Lyra Delos.

Mostly I’ve been swapping between two full arm looms (cartridge, arm wand, wiring), one with a Lyra Delos and one with a Soundsmith Zephyr MIMC.

Assuming two full ET2 arm looms implies to me that Mike is pulling the Gooseneck bolt.... to exchange armtubes ...thus leaving Azimuth settings intact for each cartridge.

Mike pls correct me if I am wrong.

Now what if.......

the Lyra has balanced channel db levels (by design) ........and the Soundsmith Cart....... not (by design) They would need different azimuth settings.
I am not saying that Mike’s Soundsmith cart is one of these Asymetric Carts but what if.........

I set the cart visually level, then fine tweak Azimuth by ear, match it up with Digital. If one chooses at this point, test out the channel separation with an electrical device. If there is an imbalance, contact the Cart manufacturer and ask if this ok. That’s what I would do.

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This got me curious so I did some digging. Here is a video from Peter at Soundsmith. Watch at the 3:30 mark.

Azimuth

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And to throw another can of worms out there.
SRA is a moving target and it depends on your records and the plant they were made at. European standards differ from American plants. Angles differ by plant. Every time they put on a new cutting stylus (every 10 hours ?) it is never put in the same way as before. Think about it.

In response to Chris - Yes I am disconnecting the tonearm at the gooseneck, so in theory I'm preserving Azimuth and the tracking line when I swap looms. I still have to reset tonearm height to get VTA right, but I rely on the runout gage readings to get back to the right height.  And of course I have to reset VTF.  I'm going to switch the Lyra Delos back into my carbon fiber tonearm tonight and see if I can hit the sweet spot.  My technique is to use a small van den hull bubble level that sits on top of the cartridge as a reference and make small adjustments and listen. Arguably the least fun part of dialing in the sound.  When I hit that SRA/VTF/Azimuth window, and it's small, the reproduction takes on a whole new character.  I especially notice it when a vocalist has backup harmony singers or is being double tracked.  I listen to those background vocals and when things are right, those vocals are entirely distinct and you can often follow their breathing patterns etc., just as if they were lead vocals.  Having said that,  I'm seriously thinking about getting a measuring device like the Fozgometer to get in the ballpark, but I'm going by ear tonight and will try to keep good notes. As Peter Lederman points out, the issue is that if the cartridge has very good channel separation, one channel may be 30db and the other 34db, those are both great numbers that would be compromised by matching output. The consensus from my reading is that the goal when setting azimuth is to minimize crosstalk. 

Hi Chris & Dave! Funnyly, I watched through all the cartridge setup videos, and the long "testicles" video about cartridges inner qualities & problems the last three days. There is a lot of common assumptions and concepts about cartridge setup, and I have / had a bit of my own. Listening through Ledermanns videos is very inspiring and like a wave of clean fresh air into the brain. He is a f... genius.

Regarding azimuth I always wondered what to strive for when cartridge / cantilever combos of very expensive cartridges can be visibly off by three or more degrees - otherwise it wouldn't be visible. 
So the cantilever/stylus can be twisted in the body, and we can assume that it's probably difficult to get repeatable precision in production below 1 degree azimuth angle.
The second question then arises: How exact is the mounting of the stylus in reference to the moving coil armature, or (around the cantilever axis rotationally) non-symmetric moving iron or magnet structures?All this results in the question: Does the coil/generator needs to be aligned exactly with the groove, or is it the stylus?Ledermann gives a clear and IMO decisive answer. The left/right tracing lines / points should optimally be on equal height – specially with line contact styli there is not much tolerance. Optimizing crosstalk often ends in tracing the upper edge of one groove / channel and getting (sometimes a lot of ) additionnal distortion.
Optimizing channel separation symmetry (as a one parameter measurement) yields in that sense wrong results.
I used to align my cartridges with mono recordings, or mono signals. I had the cartridge mono-strapped with switched +/- connections on one channel. The problem with this setup is that  signal level differences between L and R result in less clear cancelling which gives a rather broad minimum. But interestingly in off-phase mono one can still hear the distortion more clearly. Maybe one should minimize *the distortion* in that setup. I got good results when keeping an ear on the distortion. Ie. minimizing the distortion and then in the minimum /optimal zone slightly adjust azimuth angle for minimal cross-talk.
Effectively one listens to the vertical signal in that setup (as in the Fozgometers reading) – with distortion appearing in the lateral signal because of suboptimal tracing in one channel, highlighted by the opff-phase setup.
I assume the Fozgometer has an optimized way to ignore the channel level differences and thus attainig a clearer null. But IMO doing adjustment by eye only on a meter eliminates the important audible changes. Ie. eliminating an important sonic parameter, the distortion, eliminates any remaining audible hint to tracing distortions due to stylus position.
Both the Fozgometer and the Feickert system align the generator vs. the recording instead of the stylus, and therefore they are misleading (to put it in diplomatic words). And they measure only one parameter instead of the more multi-dimensional listening process. 

IMO Peter Ledermanns talks are a must hear&see for any analogue/vinyl lover.