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
Hi Doron,
I hope you haven't bought a 'bad' TT-101 😱⁉️
They are sooo complicated electronically...that it's easy to do 👀❓
Three years ago I bought my first TT-101 from Foxtan in HongKong and it arrived with the 'Power' switch permanently engaged....the 'Brake' function inoperative...the motor noisy at both speeds and shutting down after 20 seconds of play at both speeds 😵😱👎⁉️
Apart from that....cosmetically it was perfect 😎....
My current TT-101 took another year for Tommy at TopClass (also in HongKong) to find 😊
So if all the main circuitry functions correctly on yours....and you can solve the scraping issues via Banquo's suggestions.....you may be 'cooking with gas' 😜❓
My fingers are crossed for you..✌️
Regards
Hello Harold,
The Oracle Delphi Mk II:
I agree with you that the new revisions of the Oracle do not bring something special to the table (pun intended:-)). The heavier platter with the o-rings on the circumference and the nylon screws to support the journal bearing does not really do anything. I especially dislike the acrylic mat which sounds hard and lean to my ears and think that the groove isolator is a much better choice.
The Oracle suspension is probably the best on the planet. You can hit with your fist on the acrylic base while it is playing and the needle would not skip.
Unlike designs like the Avid, Linn or Thorens, the springs are suspended rather than compressed, which helps getting a piston like action rather than wobble like most sprung designs. Sound wise, it is a king of micro dynamics, like the Quad ESL of the turntable world.
It retrieves air between instruments, textures and spatial information like no other.
The two main weaknesses of the design, in my opinion, are:
1. Speed stability - the oracle motor and belt were somewhat iffy in my mind. Even the turbo power supply and newer motors do not really overcome the weakness in maintaining speed stability and avoiding cartridge drag in transient.
2. The suspension is very effective at filtering noise which translates to pitch black backgrounds but it is also a source for energy drain which robs macro dynamics. Mass loaded TT always sound more impact-full and muscular compared to the Oracle, given the same arm and cartridge.
Thanks, Halcro!

Its cooking all right. Seems to work fine once the bearing/spindle was lifted a touch. Dead quiet and knock on wood, everything seems to function correctly.
Next is to re-drill the motor cavity in my console/plinth to allow for the deeper cavity that the TT-101 requires (we originally drilled it for the shallower TT-71).

I will share my experience of the differences in sound of these two motors.

Cheers and thanks again for the invaluable help,

Doron
Doron: I especially dislike the acrylic mat which sounds hard and lean to my ears and think that the groove isolator is a much better choice.

Totally agree. My first Delphi, Mk IV had that hard mat and with that stiff (clumsy to be honest) suspension it simply sounded awful (after a cheap Thorens !). So my first experience with Oracles was a disaster. Very well, thought I in frustration and bought a brand new GOLDMUND Studio. It was slightly better in sound quality but due to its floating and thus flimsy suspension it was just another disappointment, despite of its excellent direct drive and very heavy mass. But I wouldn´t give up with those extraordinarily designed Oracles and I changed the Studio to a beautiful looking heavier black acrylic based secondhand Delphi Mk III with gorgeous gold plated brass spring towers and with the original platter with the GROOVE ISOLATION mat. Unfortunately the adjustment stems for the spring towers were a bit out of place so the subchassis didn´t quite fit the stems so the suspension was impossible to finetune :/ Then I changed the Mk III to a secondhand Mk II... and bingo ! Along the way I lost a minor fortune but got a very nice sounding TT. Heh, young and foolish was I but it proved to a happy ending.
And I agree also in everything else you say about.

This is what I mean by a finetuned suspension:
https://www.youtube.com/watch?v=Ql9Gq6ir7hA

Sorry guys, this is totally off-topic but I just couldn´t resist (grin).
Fleib, I fear we are still on different pages. I am talking about how to mount an RS-A1. To do so, you aim it at the spindle and let the stylus fall about 21mm short of reaching the spindle. It is my belief that thus you will obtain tangency somewhere near the middle of the playing surface, or wherever you prefer by adjusting the stylus underhang (i.e., the stylus hits the label a little closer than 21mm from the spindle or a little farther away, whatever suits you). If you look again at the diagram in Hiho's reference, see the arc that is shown as a dotted line. See that achieving tangency at point B will require you to adjust underhang such that the stylus falls on that dotted line arc some distance from the spindle, which I take to be about 21mm, from my memory of the RS-A1 instruction manual.

Doren, For caps in the circuit, I would not stray from the original values given in the parts manual available on Vinyl Engine. Voltage rating can be higher than original but not lower. For caps in the PS, you may wish to use slightly higher values of capacitance, but there is no need for it. Yes, replace all. Any one of them can fail any time, after 30 years. Digikey and Mouser are good sources for Panasonic, Nichicon, and other top quality brands. For only a few bucks you can buy them all.