3 New UBER Decks - Is this Turntable's SwanSong? 🦢

@gordon:crap maybe it was the early 90’s,everything but the last 10 years is pretty much a blurred image..
Best of my memory is that he & Julian Hirsch had a big brew ha ha about M.F.’s apparent flip of camps from digital to vinyl..

...tell me when and where to send the flowers....there's only so far one can take the 'system', as 'magical' as it can be.  JMHO....

@antinn, great example of a proper review. Now if all tonearm reviews were done that way we might be able to draw some meaningful comparisons. My only complaint is that the V15 was too compliant for the Tri Planar. My own experience with damping brushes was frustrating at best. 5 Hz is too low in everyone's book. No wonder bass performance suffered. Not sure how they crammed a Tri Planar on a Sota. Donna insists it does not work without significant modification but maybe that is just the more current versions.

I am going to agree with audioman85, dover for the most part, clearthinker and rauliruegas. 

I am not so sure that vinyl is here to stay. Most of us older audiophiles have large record collections which makes owning a turntable mandatory.
The people around at the time record sales exploded are now older, their kids are on their own and they have much more money to burn. While it is true that some young people are getting into vinyl, far more are getting into digital. I won't be around to see the outcome consequently I really do not care. If I did not have any records I doubt I would buy a turntable on the other hand people who point at all the problems with vinyl reproduction have obviously not heard a top notch turntable with a modern stylus profile set up correctly playing a clean record. It always amazes me how good this can sound.

IMHO the Nak TX-100 was overkill in the extreme. Typical Nakamichi. Shifting the center of the platter is going to alter it's balance which in time will do a number on it's main bearing. Many of us laughed at it. Off center records are a problem and can be quite audible. My solution was quite simple. I returned the record as defective, and kept returning them until I got a copy that was decent. 

I'm waiting for the TECHDAS AIRFORCE ZERO MK II to come out. Then I'll buy!

Re speed stability.
As has been noted, the numbers produced by the platter speed app vary from test to test. This depends upon how the tester placed the record on the spindle, there is a small amount of clearance, so the record can appear to have different amounts of eccentricity each time it is placed on the platter. Also it depends upon when the test is started relative to the point at which the arm is swinging in and out due to the eccentricity. There will be a different reading if the test started when the arm was at mid swing compared to if it was at the inner or outer extreme. You can see the impact of this on the green trace at the start of the plots. Some show an uptick or downtick at the zero second mark due to the arm being at or near full excursion, (AF0, XD1, AC-2, 1000R, K3), where one is neutral with the arm’s swing more or less at its mid point (TT-101).This biases the low pass numbers in favour of the TT-101. The length of time the test runs also impacts on the final outcome. Then there is the low pass filter that is applied to the raw data, this designed to remove the impact of the records eccentricity. It is somewhat a blunt instrument in that it also removes key data about the platters micro speed stability within each revolution.
It is possible to do multiple tests and pick the best or worst numbers to highlight whatever point you are trying to make.  A reasonable conclusion is that beyond a certain point, the numbers produced are of interest but are not particularly robust data.

But what is pretty consistent and robust from test to test is the yellow trace. (amplitude aside as mentioned above due to record/spindle positioning) The platter speed app is interesting in that it first plots the CARTRIDGE OUTPUT as a function of frequency with respect to time.
In a perfect world where the signal generator sent a constant 3150hz to a perfect cutting lathe, we stamped a perfectly concentric record and played it back on a perfectly speed stable TT, we would see the yellow trace as a straight line at 3150hz
But of course, this is impossible and one of the major deviations from perfection is that the record spindle hole is not in the centre. So if all other parameters were still perfect and we considered a non concentric record, we would see the cartridge output a clean sine wave, symmetrically centred about 3150hz with a constant amplitude per cycle.  IOW, a TT producing a yellow trace that is a badly distorted sine wave is NOT speed stable, although its speed could average 33.333.  I hope that this is self evident.
The program then puts this raw trace thru a low pass filter to remove the effect of eccentricity, we now have the green trace. But what the low pass filter does is filter distortion as well. This distortion is a graphical representation of rapid speed changes. It is no longer visible and what we are left with is a smoothed average which is used to compute the low pass filtered numbers.

A far more accurate and useful metric of the speed accuracy of a TT is to simply look at the raw yellow trace, ignoring the numbers. How close is it to the ideal symmetrical, clean, constant amplitude, sine wave?  Some of the TTs mentioned in this thread, plot significant deviation from this ideal with quite rapid and frequent speed changes.
Remember that the yellow trace is the cartridge output plotted as frequency with respect to time, any distortion of the sine wave is a change in frequency, thus a change in speed. These speed changes would be superimposed on any music that was being played. With this in mind, I invite you to look again at all of the speed plots

.
On top of this conundrum, the platter speed app does not load the system dynamically since the 3150hz tone is of constant amplitude.  This is a whole different set of  equally important measurements. We do not listen to constant amplitude, single frequency tones.

BTW two of the TT plots posted have a low frequency oscillation with a period of approximately 9 seconds. A low frequency oscillation with a multi second period like this is not uncommon and is very difficult to eliminate.

Cheers,