New Mag-Lev Turntable

When the base of the arm and the surface of the platter are not rigidly coupled, the result is that any motion in which both are not a party will be interpreted by the pickup as a coloration. One example could be a loss of bass.

In a turntable ideally there will be no slop in the bearing of the platter or the bearings of the arm so that this rigid coupling can occur. In that way if the platter has motion other than rotation, the arm is moving in the same plane and so cannot pick up whatever that motion (noise) is about. Quite simply, any turntable that breaks this rule for whatever reason will be incapable of state of the art performance.

I wonder if an isolation device under a cutting machine would be of benefit?  

Yes. And the industry made isolation platforms for lathes going way back to the old days (1940s and 1950s). In addition, the lathe we use is mounted on a special table that has adjustable pointed feet. We audiophiles were several decades late getting to the party!

Rigid
- unable to bend or be forced out of shape; not flexible.
- not able to be changed or adapted.

Yes- that is how I was using that. In addition, I expect the plinth to otherwise be as dead as possible.

Its important to understand that no plinth will be 100% rigid and dead but you do the best you can.

@Atmasphere - fwiw I enjoy reading your posts on amplifiers / preamps, but do find your posts on analog playback don’t follow my experiences sometimes. Like here. Could this be because you sell Empire turntables and have a business relationship with Triplanar ? Well thats cool;
but all you have to do in your own room is start the 15 IPS tape and then 10 seconds later start the record. Toggle between the two adjusting for the fact one is high level and one is low level. The turntable set up is very tweakable so one can learn its limits quickly this way and adjust.  Have you compared this way in your own personal room ?
Because of the eminently tweakable nature of turntables, I never set up a room with vinyl first. Digital and Tape 15 IPS has excellent, consistent bass. Once that is setup I bring in the vinyl artillery. Its that easy.

I use master tapes as a reference, and have LPs and CDs made from the master tapes. Having been there when the recording was made is an enormous help in establishing a reference! (Atma-Sphere LP 3-001 also issued on CD being one I refer to a lot)

I do sell the model 208 turntable which is heavily based on the Empire, however the ability to market this machine is really limited due to the fact that its entirely dependent on our ability to find the original machines. The 208 is also not a big seller; I base my comments more on how any LP mastering lathe is designed where its very obvious in spades that this rigid coupling concept I espouse is well-known and striven-for by the lathe producers.

Now you might argue that what applies to the lathe does not apply to playback but its pretty easy to see why that idea would be mistaken. In a nutshell, ideally you reverse the process during playback. The addition of an extra plane or planes of vibration during playback on its face sounds like its not a good idea and this is borne out in practice. At every point when we improved the plinth in the turntable by making it more rigid and more dead the closer it got to sounding like the master tape.

Regarding Triplanar: my 'business relationship' with them is limited to shows. I own several of their arms because they have proven over the years to do the best job of playing the LPs I mentioned earlier. To that end specifically: tracking is effortless, the bass is obviously better (in the recording the biggest bass drum in the state of Minnesota was employed on my insistence; it was 6' in diameter and is played both loudly and very quietly; many systems fail to bring it out properly); the mids and highs have the best definition and sound the closest to the tape of any arm I've heard.

You know, what doesn't make a lot of sense to me at all with Audiophilia, is that we have some "well heeled" Audiophiles searching for that sound; spending thousands on gear. And as we are in the analog forum here, this means - multiple turntables, tonearms, even more cartridges. Yet, they do not take a small portion of that budget, and buy a good reel to reel with one days worth of 15 IPS master tape dubs to use as a reference point . Seems like an obvious way to start at Ground Zero with a good Analog Audio Reference .... and go from there. Let it guide your journey. What better way?  Just makes sense to me.

+1.

I think a set of really good mics are a good investment too (I bought a set of Neumann U67s in 1984). The ability to use that tape machine with good mics really helps in establishing a good reference. These days I also run a small recording studio. We have Studer, Ampex, Sony, Otari and Tascam tape machines, as well as a Scully lathe with a Westerex 3d cutter head.

Hit the platter and it wobbles side to side while the arm remains static. How in the world is that suppose to track without distortion and possibly skipping. Now, if they levitated the arm on a beam connected to the same plain as the platter, e.g., Rega, and it could move in accordance to the same micro and macro vibrations I might consider it.

S'what I'm say'n!

But... when you dampen you can also lose extension.

If you are really experiencing this then the damping is not working as you surmise. Its impossible to overdamp for vibration if the damping is indeed working correctly!