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

For those who have a JVC TT-101 should check out this YouTube video.

DIY thread drive turntable

Looks like someone turned the TT-101 into a belt drive motor! Using string or thread that has no compliance, it retains the accuracy of the direct drive system with the isolation of belt drive.

Halcro, you should use the TT-101 to drive your TW Raven. :-)

I have used a Technics DD table that has pitch control driving a passive platter before and it worked!

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Thanks for the Link Hiho...😍
Very interesting.....and nice music as well...🎢
I have seen that done before...as well as two Micro Seiki turntables running in line....using the one motor and a flywheel arrangement..πŸ‘€
I studied this arrangement shown in the video for a long time.....whilst being somewhat troubled 😧 without knowing exactly why......⁉️
(Answer to the puzzle at the bottom of the page...😊)

This video demonstrates clearly how much 'thinking' some Japanese (and European) audiophiles put into the theory and philosophy of the turntable question...πŸ”ŽπŸŽΌπŸ”πŸ’‘πŸ˜
I love his obvious 'Copernican' view of the turntable surrounded by massive armpods 😘....and the 20" straight tonearm is fabulous...πŸ˜œπŸ‘
He obviously prefers the ability to eliminate skating forces (no off-set angle on the headshell)....for the slightly increased distortion of 'tracking error'...⁉️
I wish I could see how he runs the thread from the heavy stainless steel platter mat on the Victor DD turntable πŸ‘€β“That is one massive 'pulley motor' 😎
Notice also his full horn speaker system....πŸ”πŸ”š....obviously being powered by SET valve amps (although we don't see them 😰).

Answer to puzzle
The advantage of the very best DD turntables over belt-drives IMO....is their ability to cope with 'stylus drag' due to their torque and correction circuitries.
With the quartz-controlled motor attached to the platter and in close proximity to the stylus....any slowing of the speed due to 'stylus drag' is instantaneously corrected AT THE SOURCE..πŸ‘
When the stylus is separated from the correction circuitry by a thread a metre or more away.......the 'stylus drag' has a 'delayed' input which simply puts the quartz control 'out of sync'....😰

Halcro, I understand your concern and it is a valid one. When I used a DD table to drive a passive platter, I had to use the speed control and that required defeating the quartz lock feature to be at variable pitch since the two platters are not identical size. I confirmed the speed using a KAB strobe and it was rock solid. Of course you can always use the Sutherland Timeline if possible. I also did a experiment of using two identical direct drive tables one driving the other, one to one ratio, and able to retain the quart lock. And the sound is better than direct drive alone. But I ran out of table space! :)

I think using noncompliant material lessen the problem. I'm sure using a stretchy belt will throw off the speed in a weird way but, hey, we might like the sound! :)

Anyway, it's worthy experiment if you already have all the components and time. It's reversible. You have nothing to lose. The reason I did that was just so sick seeing expensive belt drive turntables using cheap flimsy motors and all that money was poured into the fancy platter for blinks.

Happy listening!

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Would love to see photos or videos of some of your experiments Hiho....πŸ˜‰
You're a 'thinker' and 'doer'.....and we need more of those...πŸ‘

Kind regards....

Thank you for the kind words, Halcro. As a person with limited means, I'm more of a daydreamer than a "thinker." As for the "doer" part, I've been really lazy lately so I am more of a slacker. There you go, I'm a daydreaming slacker bum! :)

I didn't document much when I was experimenting so I don't have much to show. Here's one picture of using the guts of two Pioneer PLL-1000 tables, one driving the other via VHS tape. I even stuck a Lenco idler wheel in between at one point. Each has their own sonic signature. The tape drive version sounded the most balance. But when I switched to a JVC table I almost couldn't hear the difference. The idler drive one always sounded different, more robust and juicy. Nothing too scientific but it was all fun. :)

PS, This forum is more about validating one's (or invalidating other's) purchase decisions, almost like a consumer guide. It's a different platform from other DIY forums I frequent. I do enjoy out of the box thinking so this thread is quite nice. :)

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