Vintage DD turntables. Are we living dangerously?

10-13-15: Halcro
And let's gets real.....no-one is going to reinvent a new DD turntable which can be built in a 'garage'.
HW did it with a cogless super motor that still can't match the performance of the 30 year old Victors and can't be made for less than $30,000.

Henry, are you saying the motor can't match the Victor or the overall performance, or both? I'm curious about the basis of this statement.
Regards,

Regards Fleib,
Here is the Feikert Speed App for the VPI Direct as published by Fremer in Stereophile and
here is the corresponding one for my TT-101.
Now all the Raw Frequency and Lowpass-Filtered Frequency figures are near identical for both turntables yet look at the General Mean Frequency comparison figures.....
The VPI Direct is 4.5 Hz above the 3150Hz Test Tone Frequency whilst the TT-101 is spot on.
Oh I know 4.5 Hz is tiny and probably irrelevant in the scheme of things BUT.....the VPI is using the most expensive and sophisticated motor for this application currently available and has 35 years of computer advanced technology to draw on yet can't match the accuracy of the 35-40 year design work of the Japanese Victor engineers...😡
But these Charts are not the most revealing part of the Feikert Speed App.
Here is the real time analogue print-out of the actual sinewave produced by the VPI Direct whilst tracking the 3150 Hz Test Tone. Ignoring the fact that it is well above the 3150 Hz frequency line.....observe the continually varying pitch of the mean frequency (a straight line is theoretically perfect) as it drops and raises tone. THIS is the real analogue graphic of the true speed-constancy performance of the test turntable.
Here is the Frequency Chart of my TT-101 and here is the long-term frequency chart of my TT-101.
Now tell me what you see and how the world of audio technology has improved over the last half century.....❓😎

Well, that is interesting. Maybe it's harder to correct speed inconsistencies of a 20 lb. platter? I don't think electronics has ever been VPI's long suit and this technology hasn't changed in the last 35 years. Harry is an old plinth builder, ironically for JVC.

You wouldn't by any chance have those charts for the TT81 and 71?
Regards,

I don't have charts for the other Victors yet but here is a video of the TT-81 under the Timeline with three arms going on and off and showing no deviation of the laser on the wall mark.
Based on this evidence and the fact that the TT-81 employs the identical forward and backward speed monitoring of the TT-101....I believe the Feikert figures would be similar.

Hi Henry,
According to VintageKnob, the TT81 does not have the double bidirectional servo. The 101 has a second quartz locked servo outside of the drive to compare phase. Looking at absolute speed, it doesn't seem to make much difference?

I think there's something to be said for a 20.lb platter on a DD. Can't say I've heard the VPI Direct, but I wouldn't dismiss it on that basis.
On the other hand, $30K would buy a bunch of Victors.
Regards,