Nude Turntable Project


I could not fit the whole story in this Forum so have had to add it to my System Page.
I am attempting to hear if a 'naked' DD turntable can sound as good as Raul claims.
Please click the link below to read the story.
NUDE TT81
128x128halcro
Halcro.

We are both blessed with having music rooms that have concrete floors sitting on mother earth.

My definition of a plinth is likely a little wider than yours. To me it is.. "the structure that maintains accurate dimensional stability between the record surface and the tonearm". I am sure that you will agree that dimensional stability in this area is critical. I have also called this structure a "loop" in an earlier post.

By that definition your very nicely built stainless steel motor support, the shelf(or floor) and the equally nice arm pod are all parts of the plinth.

It would be reasonable to expect a change in the sound, if you were to change the stainless steel support for say a large diameter cardboard tube. Likewise we could expect a change in sound if the arm pod was made from say balsa wood. I suspect that your choice of these materials was based on experience and sound logic.
Since substitution of different materials would likely alter the performance, it can be inferred that your "plinth" does have a sound.
Aigenga,
In the TT101 Service Manual it explicitly states that the bearing needs no service, which would include periodic lubrication. Bill Thalmann also strongly advised against trying to "lubricate" it. You may fairly respond, and I would agree, that Victor probably did not envision a 30-year lifespan for the product. Therefore, at this point in history, some attention to the bearing may be merited. What did you see when you first accessed the bearing? What was the condition of the lubricant, the bearing, the thrust plate? I am just curious; I don't think what you did was necessarily "wrong" in any way. What lubricant did you use when you serviced your bearing? Thanks.

Halcro,
I think what you have now is a "plinth" by my own definition. Many if not most of the best belt-drive turntables are built with solid, heavy bases that do not afford an open deck surrounding the plane subjacent to the platter; I always thought that was a good idea, as is yours. If I had it to do over, I might have fashioned my own slate and wood plinths in a more minimalist way, but I am not about to do it over. By the way, my Lenco most of all benefits from its dense slate plinth. Why re-open the argument?
Lewm, the fluid was brown and had particulates in it. The bearing looked fine, the plate is soft white plastic so was dented by the bearing but otherwise fine. I do not recommend opening the bearing up unless you have detected a problem. I thought I had made that point in my narrative. But it isn't a real issue if you do it right, and it also enabled me to put rubber/steel grommets between the motor and the frame. All for education and hobby-fun.
Gary
I am all for "education and hobby fun", dagnabbit!

The Denon DP80 bearing is also supposed to be "forever", so I've done nothing to the bearing in my DP80, as well. The fact that your bearing fluid was brown indicates it probably was a good idea to change it. However, I personally would be leery of over- or under-tightening that slot-head screw that forms the seal at the bottom of the bearing well (in the TT101). Anyway, you got away with it. The thrust plate might be teflon, probably not "soft plastic".

Did you mean to imply that you needed to access the innards of the bearing in order to install rubber/steel grommets between the motor and the frame? I am not sure why, if so.
I cleaned out my bearing as well. For no particular reason other than that Gary made it sound easy--and it was, sort of. My oil was also brown and unsightly. I used Mobil 1 20w-50 motorcycle oil as replacement. One thing to note for those considering doing this is that the screw used to access the bearing is also used to raise and lower the platter. As I found out, the platter needs to be at a particular level to avoid scraping and/or locking. It's not trivial to find the correct level and it's a serious pain to handle the unit and flipping it right side up to check whether one has found the sweet spot.

So: I pantsed a la Halcro my Victor a couple of week's back. Before I did so, I listened intently to 3 album sides and then subsequently compared the differences. I changed nothing else. Like Ecir38, I had suspected that the differences Halcro found were due to his new supporting system and not so much to the absence of the metal cover.

I'm here to report that my suspicions, at least as they pertain to my Victor, are wholly unfounded. With respect to all 3 album sides I used the changes were the same: the character of the instruments including voice became more nuanced (microdynamics?) and impactful (in terms of scale but not loudness, if that makes sense) than they were. I can better hear the music as a whole. For example, the first movement of Mahler's 9th can sound like a convoluted mess if the musical 'line' is lost. After the pantsing, I could better follow along because certain passages that were relatively obscure suddenly came to life and became 'ready to hand'. Unfortunately for me, my system still cannot reproduce the double bassess accurately--but that's another issue. Ry Cooder's guitar work in 'Into the Purple Valley' has never been as nuanced and transparent. And Paul Desmond's sax in Brubeck's 'Gone with the Wind' has never sounded so right. I am pointing out only the most dramatic cases; there are many more subtle ones.

One other difference to note is that everything seems quieter. I don't mean the noise floor has dropped, but rather that I seem to want to turn the volume up nowadays. I think the desire is connected to the decrease in distortions (trademark, Raul) that I was subjected to prior.

One potential caveat: I recently changed my headshell leads to Oyaide silver. I had them in during the initial unpantsed audition, but they might not have been fully burned in (if you believe in that sort of thing). I personally don't believe the differences I heard can be accounted for by the leads.

fyi: the copper looking thing underneath the victor is a Texas Instruments Shield. I had planned to use it underneath my platter mat but it refused to lay flat--that and I don't currently use anything but a piece of pigskin. Yet another benefit of listening to Halcro.