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.
halcro
Throw away those specs. The real units don't meet them. They are pure craziness. they are about as good as amplifier specs of the day.
Wow! I am overwhelmed. But nowhere in your many quotations do I see the words "eddy current", so is it fair to guess that you agree with me? Also, and I have no dog in this fight, nor is it a fight, I had been led to believe from my own internet reading that the TT81 differs from the TT101 principally in the fact that it does not employ a "bidirectional" servo (Victor's parlance). But I always could be wrong. I believe I got that idea from Vintage Knob. (Where else?) The main reason I targeted the TT101 when I needed another tt like I need another... (name anything useless to have two of), was that coreless motor. I think it is key to what I like about the L07D, wanted to know whether that is a general property of coreless motors or some other magic of the L07D.

The earlier Denons with induction motors: did they employ servo feedback as well? It is hard to imagine how that would work well. Did DP6000 use induction motor?
I have more than five times the expense invested in my TT-101 over the TT-81....and would love to say that the performance difference is worth the cost....?
Unfortunately (or fortunately)...that is not the case and I can honestly say that I can hear no differences between them.

Thanks for the honesty, Halcro; in the same situation, I probably couldn't bear to write those same sentences.

...according to the JVC flyer that timeltel linked to, there is no "significant difference" between the ql8 and the ql10, except the digital counter. So, you may be on to something in your comparative assessment?

It does seem odd though to cram all the added circuitry of the 101 just for the sake of the readout. And to expect people to pay nearly $1k more for it in 1977. That was the going entry fee for digital, I guess.
Lewm: "The earlier Denons with induction motors: did they employ servo feedback as well? It is hard to imagine how that would work well. Did DP6000 use induction motor?"

The one I'm know for sure uses induction motor was a DP-755, an old table without quartz lock that I used to own and saw the gut myself. In the Amp8 website there's no picture of the DP-6000 motor but there's a similar looking DP-3000 that uses an induction motor. I believe all the 4 digit series tables have induction motor and they all use a tapehead reader for servo. The later 2 digit series such as DP-75, DP-80, etc... went back to motor with magnet but retained the tapehead servo system.

Halcro: "HiHo, Your interest in the Victor motors seem to have been ignited by your experiences with the TT-71.....is that correct?"

Long story. I can say it is one of the tables that got me interested in JVC products and DD genre again. Technics SP10Mk2 was my table for the longest time, over 10 years before the DD revival. Always got laughed at by my audiophile friends for not using an "audiophile approved" table a la Linn. But I ignored the noise. Then there was a period I didn't work so I had all the free time to experiment. For whatever reason I didn't use the SP10 and started exploring belt drive and got into the Empire 208, still an excellent table. I just missed the conciseness of the DD and low noise so I decided to give DD another try. I bought a bunch of DD tables for experiment, TT71 was one of them, also included models from brands like Pioneer, Denon, Kenwood, Sony, Technics, JVC, etc... Up to that point I hadn't encountered any table with coreless motor and then one day I got to listen to a dirt cheap Pioneer PL-300 and it had a smooth quality that reminds me of belt drive so I gutted it out and discovered it had a coreless motor. Ever since I started looking for tables with coreless motor and they always have that smoothness I crave for. There are some non coreless exceptions, of course, such as Sony PS-8750 and Denon DP-60. You can call this smooth quality euphony or distortion or whatever. All I know it has a sound I enjoy -- neutral or not, I couldn't care less. It was then I relistened to the Technics models, SP10Mk2, SP25, SP15, SL12000mk2, SLM3, SLM2, etc.... none satisfied me. (Although the sleeper in Technics is really the SP15.) When I started with the SP10mk2 -- college days? -- I was deeply into punk rock and the bass dynamic and tightness is perfect for that musical genre. Playing The Clash's "Police and Thieves"was great way to show off the Technics. But as my musical taste expanded, it no longer could satisfy me in other music, that often criticized sterile sound is true for me. Technics does not represent the best of DD tables, there are many options. It's unfortunate many people dismissed the DD genre just because they didn't like the Technics without thinking there are at least half dozen worthy brands out there.You just have to be open-minded about it. So, that's the gist of it.

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Some of the quoted specs Timeltel provided were from Pioneer P3 and P10 and had nothing to do with JVC. Wrong links!

It appears the prose was written using Google Translate program with very awkward phrases.

Happy Listening,
Lewm,
The speed problems on my TT-101 were not caused by the Power Switch.
The Power Switch began playing up (not turning OFF) about 6 months ago....and that's when I discovered the benefits of leaving the Victor 'powered up' 24/7.
Surprisingly....when I began doing that (out of necessity).....the switch began working again but switching it OFF.....produced the fault again.
That's when I wrote about the benefits of 24/7 Power for solid state DD turntables.
My Tech replaced the switch which is activated by a gear drive which advances one click at every press of the POWER switch......however in doing so....a small glitch appeared whereby when the power switch is activated now.....the platter starts spinning immediately whereas previously one needed to press either the 33 or 45 to start the platter.
As I now keep the unit powered 'ON' 24/7....this is not an issue for me.
Another glitch since the repair is the brake function which you mentioned.
Previously when the 'STOP' button was pressed...the platter instantly stopped due to the reverse current in the drive circuit....and then reverse spun for a second before stopping. This reverse spin was due to my removal of the stock heavy rubber platter mat which I have substituted with the lightweight Victor pigskin.
Now however, when the 'STOP' button is pressed.....the platter instantly stops but reverse spins for a few seconds longer than it previously did.
I don't know whether to have this and the Power Switch issue looked into at the end of my 3 month Warranty period?

The reason I finally had to take the TT-101 to the Tech was that the digital speed read-out began indicating widely varying speeds at both 33.33 and 45 rpm.
Since the caps and soldering replacement.....this appears to be solved.