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

Michael Fremer has recently reviewed three new turntables designed to be the 'Last Word', 'Cost no Object' STATEMENTS!!!!........Do I recall hearing this claim before??
I love Mikey and have followed (and trusted) him for decades.
He has been the longest and foremost published 'champion' of the superiority of vinyl (uber alles) in the world.
I am thus ecstatic that he has been able to listen and compare these decks in his own room, with his own equipment virtually side-by-side
It's almost a 'given' that he will be the ONLY person on earth given that privilege....

So what Mikey HEARS.....is indisputable

Given his 'character' and desire for accuracy and honesty.....years ago, Mikey started including some 'objective' measurements in his turntable reviews.
These measurements were done utilising the Dr Feikert PlatterSpeed App which has since been discontinued.
As the App only worked with the Mac iOS of many variations ago.....Mikey has kept an old iPhone which can still operate the App.
The PlatterSpeed App had a few technical limitations.....
Foremost amongst these, was its dependence on a 7" record with an embedded 3150 Hz Frequency track to produce a test-tone which the App could process through its algorithm to produce the graphs and all the corresponding numbers.
To stamp hundreds of 7" discs with perfectly 'centred' HOLES is a nigh impossibility.
It's almost impossible to do it with a 12" disc!!!

This means that ALL the figures produced in their Chart Info are dubious and mostly UNREPEATABLE!!!!
I have Chart Infos for the same turntable/arm combination but with the 7" disc moved slightly producing different figures.
I even have Chart Infos produced with the same turntable but different arms ALL with different figures (the arms are in different positions surrounding my TURNTABLE).

So what is my point......?
The GRAPH produced with the PlatterSpeed App is accurate and USEABLE when looking at the 'Green' Lowpass-Filtered Frequency.
If the hole was PERFECTLY centred.....this 'Green' line would be perfectly STRAIGHT......but only if the turntable was maintaining its speed PERFECTLY.
The wobbles in the 'Green' line are due to the hole's eccentricity as well as any speed aberrations.
So the best performing turntables are those with the most constant and even wobbles approaching as closely as possible a STRAIGHT LINE.

Now the SAT Direct Drive Motor is actually the same as Technics developed for their latest SL-1000R except with some bespoke modifications.
It appears that SAT have corrupted what is a very good DD Motor unit....🥴

Mikey says that the OMA-K3 produced the best PlatterApp figures of any turntable he has tested 👏
Does this mean that the OMA-K3 is the most accurate turntable of these three decks.....or maybe of ALL turntables?

Mikey can't (and won't) test and review products from the past which are no longer produced because that's not his job!
But wouldn't it be great if someone WOULD review products from the past against the modern equivalent?
Classic turntables with reputations....gravitas...like the legendary EMT 927 and Micro Seiki SX-5000 and SX-8000.
And what about the NOW lauded Japanese DD Turntables from the '80s...the 'Golden Age' of Analogue?
  • Technics SP-10Mk3
  • Kenwood L-07D
  • Pioneer P3
  • Victor TT-101
  • Yamaha GT-2000
Because we know that Direct Drive is now 'Flavour of the Month' for the new Uber Decks due to their superior speed accuracy....a 'Flavour' that started with the legendary Rockport Sirius III.
But what about Belt-Drive units like my 20 year-old Raven?
So much for science and technology.......

We can do things today that were only dreamt of even 10 years ago
Except learn from history, harvest experience, expertise and craftsmanship......

Here endeth the Sermon for today 🤗


128x128halcro
halcro's avatar
halcro OP
2,664 posts
 
I introduced this Thread by describing the limitations of the PlatterSpeed App that Michael Fremer has been using for years to test turntables.
The GRAPH produced with the PlatterSpeed App is accurate and USEABLE when looking at the 'Green' Lowpass-Filtered Frequency.
If the hole was PERFECTLY centred.....this 'Green' line would be perfectly STRAIGHT......but only if the turntable was maintaining its speed PERFECTLY.
So the best performing turntables are those with the most constant and even wobbles approaching as closely as possible a STRAIGHT LINE.
The yellow RAW Frequency Plot is what is measured from the 3150 Hz Test Tone and makes NO compensation for the record 'hole eccentricity'.
The 'Green' Lowpass-Filtered Frequency uses the PlatterSpeed Algorithm to 'filter' the 'hole-eccentricity' and produce an accurate graphical plot of the turntable's performance.

If we didn't have the GREEN Frequency Plot that PlatterApp gives us......we wouldn't need PlatterApp at all!!! 🤪
We could ALL just do a Plot of the RAW Frequency response of a random 3150 Hz Test Tone 🤗 

Having been embarrassed by the results of the OMA-K3 compared to the 40 year-old Victor TT-101.....Richard Krebs (the designer of the "most powerful turntable motor on earth") now wants an AUDIT of the 'votes cast' and disqualify those votes shown to be unfavourable to HIS candidate and count only the single vote he believes will allow his turntable to win 😂

The following Plots are done with my 40 year-old Victor TT-81 DD Turntable (bought for $500) with the Test-Disc fixed in one location and the three differently positioned tonearms playing the Test-Tone.

TT-81 with WE-8000/ST 
TT-81 with FR-64S 
TT-81 with DV-507/II  

Note the almost STRAIGHT line of the 'Green' Plot for the WE-8000/ST.
The OMA-K3 can't get close.....

Now the fundamental revelation of these three Plots, is that whilst the YELLOW 'Raw Frequency Plot' varies wildly for all three arms.....the GREEN 'Low-Pass Filtered Plot' remains relatively stable and consequently USABLE!!!! 👏

Richard Krebs however, prefers to make his 'scientific' judgements from ONE meaningless RAW Plot.......🤯
halcro's avatar
halcro OP
2,664 posts
 
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?
I can't see a clean, constant-amplitude sine wave for the OMA-K3...?
A clean sine wave, symmetrically centred around 3150hz with a constant amplitude for each cycle. As we can see, advances in technology have clearly improved the situation.
 I'm looking for that clean sine-wave but I just can't see it for the OMA-K3?
Please help me here.....🙏
dover
2,262 posts
 

@halcro


It’s all smoke and mirrors and fanciful postulation from the uneducated. It is not possible to measure wow & flutter using a test record.

If you use a rotary function generator to measure the turntable performance directly off the platter, the results will be more accurate than any test record.

For an explanation from someone who actually has a degree in physics and acoustical engineering - Bruce Thigpen of Eminent Technology.

Here is Bruces explanation from his Eminent Technology website.

Bruce has many patents and inventions including his unique air bearing tonearm, rotary subwoofer, vacuum platter as implenmented by SOTA, and many others.


Bruce Thigpen -

Reviewers have incorrectly attributed wow and flutter to the turntable. Since the advent of the belt drive turntable, wow and flutter has been purely a function of tonearm geometry, the phono cartridge compliance with the elastomeric damping, and surface irregularities in the LP. In our own lab we have measured many high quality turntables using a rotary function generator directly connected to the platters of the turntables.

The measured results are usually an order of magnitude better than the results using a tonearm and test record (conventional wow and flutter method). Further proof exists if you take two tonearms, one straight line and one pivoted and mount them both on the same turntable. The straight line tonearm will give a wow and flutter reading with the same cartridge/test record of about 2/3 to 1⁄2that of the pivoted arm (.03% < .07% to .05%). This is because the straight line tonearm has a geometry advantage and lateral motion does not result in stylus longitudinal motion along the groove of the record.

Another proof is to take two different cartridges, one high compliance and one low compliance, and take measurements with both using the same turntable and tonearm. The reading of wow and flutter will be different. All wow and flutter readings are higher than the rotational consistency of the turntable.


halcro's avatar
halcro OP
2,664 posts
 
@dover 
It’s all smoke and mirrors and fanciful postulation from the uneducated.
👍
I've heard nothing but positive reports about Bruce Thigpen and especially his ET 2.5 Airbearing Tonearm.
For years I've dreamt about installing his ingenious TRW-17 attic-mounted subwoofer 🤔

Thanks for posting that interesting article from him.
Maybe that's the reason each different tonearm produces a different result on the same turntable....?
dover
2,262 posts
 
@halcro

Maybe that’s the reason each different tonearm produces a different result on the same turntable....?

Very much so. I have had a lot of arms, including the ET2 on my Final Audio VTT1 TT over the years, with the same group of cartridges.

Here is a gem from JCarr on coherency -

jcarr358 posts
09-15-2021 5:23am


While cartridges are important, their tracking ability, tonal balance, naturalness, dynamics, pitch definition etc. all can be hugely affected by the choice of tonearm (and phono stage, and setup).
Musical timing in my view is not only affected by TT speed stability, but also arm/cartridge/phono considerations. From my own ears, Bruce’s assertions with regard to his linear tracker and wow and flutter are on the money.
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