Tables That Feature Bearing Friction

Dear Kirkus, yes, I have put some money in that project back then, but I got paid back and in the end I did not loose any money on that project.
As I usually do like to link philosophy with my audio discurses, I must however admit - not today . I am not in the mood - I am afraid. Most likely it will brighten up again tomorrow... ;-).
So rather plain and straight speak now.
So far my odessey in audio has been - on the large scale - cost neutral. I rather wanted to illustrate my point that all too often we do give in too easy. All the money I did put in that project in the early 90ies did not come easy. As I certainly always had to work for my money I wasn't too tempted to throw it away. I did put lots of work into that project - much more than money.
I wasn't on a field campain just to bring as many troops as possible on the battlefield as to crush the enemy by simply overwhelming him by sheer number and brute force.
From the plain dimensions this may look as just another gigantic egomatic turntable where weight and money were the driving forces and the brain was replaced by the big wallet.
Certainly not so.
Cost was an object indeed.
Sadly enough - I do not have money to burn.
Not back then - not now.
Being self-employed means you work everyday and on your own (your own risk too....).
I am certainly much more on a budget regarding my audio passion compared to several other Audiogoners.
Thats why I designed my own turntable, amplifiers and speakers.
Because I am on a budget AND because I did not find what I was looking for.
There was much more research put into that project than my mere words and the picture can tell.
It may however give some reason why I am not too impressed by the "state of the art" turntables of today.
Maybe I just want to say:
I know what I am talking about ............ nothing else.

BTW Raul, one sample of the turntable was in Mexico City from 1993 to 1998. The owner was (and still is...) the former director of BMW Mexico. I sat up the table in your impressive city.

P.S.: agreed on the ET2 - it was just mentioned to clarify the point why the TT had several individual adjustable air supplies for the many different designs in airborne tonearms around in the early 90ies - all having different needs.

I wasn't on a field campain just to bring as many troops as possible on the battlefield as to crush the enemy by simply overwhelming him by sheer number and brute force.
From the plain dimensions this may look as just another gigantic egomatic turntable where weight and money were the driving forces and the brain was replaced by the big wallet.

I didn't mean to insinuate that these were at all your motivations, my apologies if it came across that way. I was simply trying to give a little counterpoint to the general discussion, and make the point that the consideration of cost isn't necessarily anathema to the pursuit of perfection.

Lewm did bring up the string . . . I'd appreciate it if you could explain some of the dynamics involved here, as I don't have much experience with thread-drive turntables. While the mid-1980s Micros and such are designs I've always admired and enjoyed listening to . . . I've always been a bit mystified as to how such a thing as the alignment of the pulleys, the tautness of the string, etc. (which strike me as critical parameters) were left up to the end-user to get right, when there was obviously so much effort into removing variability from so many other aspects of the mechanical design. Also seems really inconsistent with regards to temperature, and wear/stretching of the string itself. Are these significant factors, and does it ever bug you that maybe with sub-optimum setup and maintainance, your designs over the course of the years may not be delivering the performance you designed them to have?

Dear Kirkus, I know that these were not your motivations - I just wanted to set some points clear as the turntable sure looks like a "mammoth" in the picture and thus the above mentioned suspect might easily arise. But - thank you.

As for the string - just briefly and preliminary, as I have to leave the computer soon:

The basic idea / principle is to have a homogenous mass put into constant rotation and then let the inertia do the job. The string in its kind of "slip-coupling" (which is kind of tricky to set-up and needs a calbrated spring gauge to ensure the perfect "non-grip") does have only one job (after bringing the platter on constant speed once):

- prevent the platter from getting slower.

All I can say - and this time I just plain ask you to take my words for granted - is: it works extremely well. We made long period measurements in MTU in 1992 and the derivation from 33 1/3 was (short-period as well as long-period derivation measurements) as close to zero as possible (measurements were taken with laser beam and calibrated circular stroboscope foil).
And - yes, the measurements were made while stylus was in the groove.
This is a huge inertia (the platter is 326 mm in total diameter - 108 lbs) in motion.
Once in motion on the desired speed, there are no derivations. The air resistance, the bearing friction (...the stylus drag..) these are all constants and thus the rotation stays constant.
It however takes about 2:35 minutes to reach constant speed........
The string just have to be dyneema or kevlar derivate and the coupling has to be precise.
But it works marvelous and watching it work, you get a certain "feel" of "completeness" and "natural move".
Audio phrases......

Time to get off.
Good night for now.

Dear Dertonarm: Thank you about your system, very nice. No public comments from me other that : yes, for me is of some help to understand ( between other things ) part of your whole audio " thinking/mind ".

Regards and enjoy te music.
Raul.

we can not achieve perfection - we can only try. The long string is no compromise at all. Yes, the string has no stretch at all (a special kevlar derivate). The point is not control of the platter rotation. The point was to prevent the platter from loosing any speed. Control is futile.

Some months ago I tried different belts after reading the article from Conti (BASIS Audio) about it. I bought a few from different Manufacturers and made some test runs with the Micro Seiki 5000 (Belts from Raven, Basis, DaVinci, Amazon, Kuzma, Roksan, Transrotor, Seiki original....and even various ) Strings.....
The result made me curious, because there were big differences in sonic presentation (smeared Details, dull bass, different depth of soundstage etc.)
Even with string was different among themselves (slip, grip, noise etc.)
This was a very interesting experience for me. Some belts are really lousy, I was dissapointed, there are much discussions about more motors, or powerful motors...after all, I am smiling about that.
The goal should be to find the few, who do it right. I mean, really doing right.
No talking about that (most "manufacturers" today prefer doing this).
When one or he other reader want an upgrade, before selling the whole Turntable, try this first.
Could be interesting :)

Belt Test 1

Belt Test 2

String Test 1