aluminum platter vs Acrylic not what I thought


I recently got to hear a VPI scout with an aluminum platter and various platter mats.  I am having a hard time trying to understand where the fascination with aluminum is coming from.  The acrylic sounds far better.  Its not even close to my ears.  Is it that some people just never heard the scout with the acrylic platter?  I would strongly encourage anyone who is looking for a used scout with an acrylic platter to really take a good look at it.  It sounds much more like real music and for what these used scouts are going for, they are an incredible value.  Maybe its just system/cartridge synergy.  I actually thing the scout with the acrylic platter sounds just as good if not better and quieter than the classic with the aluminum platter.  The scout sounds more like an older Aries than the Classic does.  The advantage of the classic is the longer arm but I mean for many people, I am not sure you can do much better table than the scout with the acrylic platter for anywhere near to what they go for used and I would say they you could look at tables costing much more and still not get the music satisfaction in many ways that the scout accomplishes.  They just seem to portray the musical experience in a way that sounds right.  Aries and scoutmasters with acrylic have to sound killer.  The only platter that is as good that VPI made are there lead and hybrid metal aluminum/acrylic platter tables.  I think VPI is going in the wrong direction with aluminum.  To me the disadvantages far outweigh the benefits.  Others may disagree but if you find scout w/acrylic for a good deal, I would be all over it.  Sometimes you just don't know what ya have so I will probably hang on to mine for a while.
tzh21y
FWIW the original VPI platter was aluminum with a lead insert. When that was replaced on the same turntable with acrylic, also with a lead insert, the review in the (then honest) Absolute Sound said that the original aluminum was clearly awful and that the table really came alive with the acrylic/lead platter. I can personally vouch for the improvement. So acrylic/lead platters became the mainstay of VPI through the early TNT days. The original TNT platter is a great platter and I still use one on my much modified TNT. Lead, by the way, is a perfect substance for that use, not only heavy, but acoustically dead. Try ringing a bell made out of lead!

Eventually, said to be due to environmental concerns, VPI replaced the lead inserts with various metals under the acrylic. Later there were also acrylic platters with no metal. And then the return of the Super Platter: acrylic and steel. Some of the more expensive tables in audio still use an acrylic, or other close plastic material, for the platter.

When VPI went back to aluminum, I was kind of shocked given the history. Back to the future. From all I have been able to gather this was clearly a move simply to lower the cost of production. Apparently high quality acrylic was getting more expensive, and aluminum is cheap and easier to fabricate into platters. As in the original aluminum days, users are scrambling for platter mats of all kinds. And they should.

I have experienced the difference and would never change my platter for the aluminum one.

So bottom line, the OP has a point.
We tried different mats and even though they did make a difference, not always better, it just seemed that some frequencies were still affected by what must be the aluminum.  We both came to the conclusion that the Aluminum platter is just not giving us the benefits we hoped for.  Just could not get away from the overly energized platter.  Too much energy.    I guess what I am saying is the Acrylic platter VPIs are really good.  Considering what you can get them for it is a steal.  I have heard the lead and acrylic mix platters that melm spoke about and he is right, no question, no doubt. 
Yogiboy, I would agree, lead was very good indeed.  Dead as hell in a good way.
I've been having great success with a 10" vinyl record as a platter mat on my 401. It's such a quick, cheap test. You might be surprised.

Atmasphere said:
A correct platter pad will have the same hardness as vinyl so that any vibration from the LP can be absorbed.

Aluminum and any metal for that matter is far too hard.

Acrylic is too, but obviously less so than metal. IME, the harder the material, the more issues with high frequencies.

To expand on Ralph’s comments, you’re trying to absorb and transmit spurious vibrations away from the stylus tracking the groove so they don’t reflect back into the cantilever/motor assembly of the cartridge. The key to this lies in matching the speed of sound of the two materials (platter surface and record).

Our plain-Jane, PVC platter did this extremely well (the “V” in PVC stands for vinyl), but the market was fascinated with flame polished acrylic. The PVC was as much of a technical success as it was a commercial flop. And so it goes …

Now, you can work with aluminum but it gets tricky. In an after-market context, you can try playing with mats, but it will be a long, bumpy road (or … you might get lucky on the first try).

The key in working with materials that don't interface well with records (from a vibration transmission perspective) is to do this in stages - starting with an ideal platter surface, and working through intermediate material transitions,. 

This is how we approached our composite (Gavia and Stelvio) platters.

Lew said:
For what it’s worth, I have not liked acrylic mats or platters in the past, but probably that’s just me. The only platter per se that meets your criterion pretty well, Ralph, is one of the several options offered by Thom Mackris on his Galibier turntables. It may be made of Delrin, but I cannot recall.

Top to bottom, the platters are carbon fiber, PVC (for the Gavia Platter) / Brass (Stelvio Platter - 14 Lbs. worth of it), and aluminum, along with damping chambers in the aluminum.

… Thom @ Galibier Design