Vintage DD turntables. Are we living dangerously?


I have just acquired a 32 year old JVC/Victor TT-101 DD turntable after having its lesser brother, the TT-81 for the last year.
TT-101
This is one of the great DD designs made at a time when the giant Japanese electronics companies like Technics, Denon, JVC/Victor and Pioneer could pour millions of dollars into 'flagship' models to 'enhance' their lower range models which often sold in the millions.
Because of their complexity however.......if they malfunction.....parts are 'unobtanium'....and they often cannot be repaired.
128x128halcro
Dover has comprehension problems (as well as others) with both my statements and those of Markus who designed the Feickert software.
The spikes in the generated sinewave are NOT "speed corrections generated by turntable error correction".
They are simply part of the software program to compensate for non-centricity of the test record and the effect it has on the steady-state 3150Hz test tone.
The previous software plot ( which I included) does not include these spikes.
How anyone can interpret it otherwise is beyond belief. Markus is amused....
Why don't you contact him yourself Dover to explain your interpretations...?
Halcro,
I don't know what test record you're using, but this software, app, or whatever, is giving an erroneous impression. The TT101 has W/F 0.02% WRMS, and speed deviation of zero w/up to 120g VTF.

That W/F is at the limit of conventional testing ability. With a DIN 45 465 test disc w/locked groove and centering, you can test to 0.06% unweighted wow, if you have the program.

Below is a link to Kevin (KAB) talking about positional updating tables vs. linear frequency generators. It's not what we're discussing, but might give some perspective:
http://www.kabusa.com/myth2.htm

Regards,
Fleib,

You bring up a good point. There is no piece of equipment that can measure W&F of true absolute '0'. So at some point in this discussion, it is going to have to be accepted that the TT-101 is probably at that threshold of being
non-existent in this regard of 'measurable' W&F
A good point guys...
I recall on another Forum where someone used the Feikert Speed App to measure a CD player (a theoretically perfect 3150Hz sine wave) yet it produced a frequency response chart very much the same as the TT-101 albeit with slightly smaller ripples.
Whilst we are talking up the benefits of SOME vintage DD decks in relation to speed consistency and low wow and flutter.....it is not to say that surprisingly good results can't be obtained from certain belt-drive turntables.
Here is the Frequency Plot for my Raven AC-2 which is almost as good as that for the Victor and is better than that of even the VPI Direct...😱
Compared to other belt-drive models like the Wilson-Benesch and George Warren that I showed previously, it shows that 'smarts' and 'implementation' is everything in the world of analogue.
It also explains why I can happily listen to either of my turntables...😍
The main differences between a really good belt-drive and a really good direct drive is in the micro and macro handling-ability of 'stylus drag'.
With the Victors, the Frequency Charts (and Timeline tests) are the same whether an arm (or two or three) is tracking the record or not.
With the belt-drive however, the speed is different between tracking a record and not.
Now this may seem initially like no big deal...?
Just adjust the speed to be accurate when tracking a record....
But the 3150Hz test tone produces a steady state undemanding mid-frequency sine-wave.
The music embedded within vinyl grooves is an ever-changing torture test of low to high frequencies totally unlike the steady test tone.
If the belt-drive deck changes speed with the cartridge in the groove....it is also changing speed (at the micro level) with every change in frequency and amplitude within the groove.
The fact that most of us are not audibly aware (or bothered) by such an occurrence is highlighted by our abilities to be unperturbed by the Wilson Benesch.
But there is just something elusive to the experience of great speed-consistent analogue reproduction when you get used to it..😋