VPI acrylic vs. aluminum

What people miss by saying acrylic or aluminum platter (depending on the era) is the latest platters are offered with an inverted bearing that has a substantial impact on it's own. By just referring to either of these platters without including whether or not it's an inverted or non-inverted bearing is missing part of the equation, IMO.

I've have personal experience with a Mk.III platter/non-inverted bearing (TNT 3.5) on my highly modded HW-19 MkIV and in blew away my TNTII platter/ non-inverted bearing combo. (quieter, more bass expression/ impact, more musically involving).

My Classic 3 Sig. SE has the new platter/inverted bearing. A comparison between these two tables is not fair. I will say that one noticeable improvement on the metal platter is there is no static charge and the presentation is much quieter.

melm, I do have an advantage of actually owning/hearing both types. According to you previous post, you've never been willing to give up your old combo for anything that came later.

FWIW: (When I did my above comparision, I didn't use the beefier bearing that came with the 3.5 platter. They are both interchangeable with regards to being able to use both platters). So the platter WAS the difference I heard!

The non-inverted bearing is subject to more things being in absolute alignment, and also that alignment needs to be accurate on much more "bearing shaft surface area". Additionally, there is the superlative machining of the Classic platter and the fact that it is self leveling.

The static charge on any acrylic latter is evident when removing an lp from an acrylic platter. It is not a factor in this regard on a metal platter.

You seem to make a lot of final conclusions without the benefit of actually hearing/experiencing them for yourself.

To be clear, maybe when I said "the presentation is much quieter", I should have said the presentation has a quieter background.

If my re-stating your previous point to make my opposing point seems like a personal attack, I apologize.

It may be true that your particular platter/TT/non-inverted bearing works best for you and your tastes. I have no reason to contest this.

The fact that a non-inverted bearing is more expensive to produce, (on that one merit), surely doesn't mean that it is superior in every application. I've found through the years with many things, simplicity in design and execution is more often than not, superior in most ways. In a non-inverted bearing, the more surface area of the bearing shaft = more surface area contact which causes friction/vibration/resonance.

The Classic platter... in addition to being self-leveling, is also self-centering.

Happy Listening.

I can only speak to my experience with the platters that work with non-inverted bearings where the platter sits on top of the bearing supported be three set-screws where the spindle has rubber o-ring/s to off-set (some) of the play that is inherent in this design.

I use a square or something that I know is square (sometimes a business card works if checked for square, or you could invest in a dial indicator) to set on the plinth close to the platter as it spins. I've always seen the need to adjust the platter on the bearing by sliding it slightly in one direction in order to get close to no wobble or "out-of round" as possible. (With the Classic platter/bearing design, the only way for it to be off-center would be for a machining error, otherwise, there is no play there). (I find it hard to believe that anyone who's ever checked this, hasn't experienced the same thing.) This is why when I say the Classic platter is "self-centering" it makes a big difference. The only other possible measurement left to deal with is the precision of the machining of the run-out tolerances for the platter to run true, therefore have correct, consistent speed leading to more musical satisfaction. I believe, according to VPI, the Classic platter has closer machining tolerances that most older platter designs. (This is why I care.)

When one obtains more expensive, more closely machined devices... this is where a lot of the improvement in sound quality originates and separates good sounding components from great sounding components. (Another reason why I care.)

One more point: in anything mechanical, in the case of this forum post, (turntable, tonearms, cartidges,) machining tolerances are extremely important in overall end musical satisfaction. Take some cartridge lines for instance, the only difference in some models are the closer tolerances that were found after the manufacturing/machining process was completed for a specific model, and only, after final testing of these parts, found to be much better sounding, therefore the manufacturer creates a new model that sounds better/costs the end user more (costs the manufacturer no more) from the batch of original cartridge parts for one specific model.

melm: With all due respect, I've read through this discussion a few times. Even though I've tried to explain my personal experiences with these differing platters/bearings, you have, (without as much personal experience, as you stated), have again & again asked questions that show that lack of experience or thoughtfull reasoning that should be considered here. The questions you've continued to ask, show this. It seems you have either an unwillingness to accept others' personal experience without careful thought or the fact that ongoing improvements in mechanical design/machining tolerances, just may be an improvement to your listening experience. For these reasons, I will not post here again.

I only hope the OP has gained some insight here.

I hope you all have a good day.