@ cats squirrel: I’d be interested in your views on materials for platter mats. Ones made of copper or gun metal seem to be very well liked. Here is a quote from the website of the manufacturer of one of the most respected ones:
“Weighing 2.2 Kg and 5mm thick, . . . . . . . The additional mass does increase the kinetic energy stored by the platter while affording very effective damping of the unwanted resonance that many alloy platters can contribute to the sound of vinyl replay. The Gunmetal also provides a more appropriate impedance match allowing energy imparted into the vinyl by the stylus to be dissipated harmlessly.”
I would have thought that metal would not be particularly good at damping resonances. Also, what do you think of the impedance match comment?
Would a platter made of panzerholz be better, assuming you could get it machined appropriately?
“Weighing 2.2 Kg and 5mm thick, . . . . . . . The additional mass does increase the kinetic energy stored by the platter while affording very effective damping of the unwanted resonance that many alloy platters can contribute to the sound of vinyl replay. The Gunmetal also provides a more appropriate impedance match allowing energy imparted into the vinyl by the stylus to be dissipated harmlessly.”
I would have thought that metal would not be particularly good at damping resonances. Also, what do you think of the impedance match comment?
Would a platter made of panzerholz be better, assuming you could get it machined appropriately?
Hi Hugh,
there seems to be a lot of noise, so you need to increase the accelerometer input signal level. You should get just a few cycles of the fundamental. [Ironically, it is much more difficult to measure the damping factor of a material which has a high damping factor, because there are far fewer peaks!]
The Panzerholz should sound 'dead', maybe it's not Panzerholz!
Fc is a consequence of thickness, Fc is proportional to the thickness squared! One should be aware of the consequences of thick panels/plates, but not use it to aim at. Another problem with critical frequency is that above it, the radiation of sound is asymptotic towards 100%. So you will hear it, depending on damping, of course.
I think you mean 'over done the attenuation? Yes, you have
Panzerholz has a DF of about 0.6 at lower frequencies, rising to 0.9 at higher frequencies.
The 'Newplast'® is the one I recommended, as it has about twice the DF of 'Pasticine'® But the amount needed is quite large, as mechanical impedances have to be matched.
HTH
The type material is not dependent on type of drive, but the results you get maybe.
Cats Squirrel,
Thanks for all of that!
I'm pretty sure it's Panzerholz, but I wonder if there's variations in the amount of resin. Some parts don't look as dark as others.
I do have a bag of Newplast. I'll compare it sometime to Ductseal and Green glue.
Hugh
Hi,
the use of a metal platter mat goes against everything I have experienced and all the scientific papers I have read! Metals (ALL commonly used metals) have just less than the square root of damping ability. My cynical side would say that as the audiophile has paid megabucks for his/her copper disc, then, of course, it's better than sliced bread!!
It can be proved quite easily that vinyl records can pickup audio sounds from the loudspeaker very easily, which is then captured by the stylus, eventually amplifier and relayed to the loudspeaker/s. If the sound is loud enough, feedback will prevail, if not, the vibrations of the record will still interfere with the fidelity of reproduction.
What is needed is a platter mat made of a damping material which has a very similar mechanical impedance to the vinyl record, so that vibrations can b transferred to the mat, where they will be damped. But the mat must have a very different mechanical impedance to the platter, which must be damped itself, so that noises/vibrations from the platter are not conveyed to the platter mat/vinyl disc. [A puck or weight can be useful, here.
Although a vinyl disc and gunmetal disc can be made to have the same mechanical impedance, the thickness of the gunmetal disc would have to be around 480 microns thin to quantitatively transfer the vibrations from the vinyl record to damp it, which it can't, as it has very little damping ability.
In this example, sound damping seems to be in the mind of the manufacturer/purchaser.
Last edited:
OK Hugh, but you bring up a very important point. Most materials (man-made, but even natural stuff as well) is seldom 'perfect' when it comes to homogeneity, even materials which are supposed to be isotropic. I have been told that even natural wood from the same tree trunk can vary quite a bit.
Also, remember that what you hear is only part of the vibrations, mostly above Fc, but some below as well. Also, it depends on what you hit the test material with!
Last edited:
Re: "Also, it depends on what you hit the test material with!"....
Yes, agreed. I like that hammer you suggested. What I found was that when I hit harder, there's more harmonics and the decay takes longer. So, soft taps are better.
This last round of tests was 1/4" steel bearing balls rolled down a 20" incline (so as to get a series of uniform pulses not dependent on my Hammer skills). I did find that a 5" run was a little cleaner, but this lets the noise dominate more.
More fine tuning to come.
By the way, when you said the pulse should decay in a few cycles, did you mean 100mm x 100mm pieces? Or does that comment also apply to a full sized plinth?
Hugh
Yes, agreed. I like that hammer you suggested. What I found was that when I hit harder, there's more harmonics and the decay takes longer. So, soft taps are better.
This last round of tests was 1/4" steel bearing balls rolled down a 20" incline (so as to get a series of uniform pulses not dependent on my Hammer skills). I did find that a 5" run was a little cleaner, but this lets the noise dominate more.
More fine tuning to come.
By the way, when you said the pulse should decay in a few cycles, did you mean 100mm x 100mm pieces? Or does that comment also apply to a full sized plinth?
Hugh
The type material is not dependent on type of drive, but the results you get maybe.
Hi,
You mean that perhaps with DD or Idler is more effective than to a Belt drive floating type?.
Tks n rgds
Adelmo
decay rate, for a particular material, should be independent of size of test piece. Something which may make a difference is how the test piece is mounted, and what is at the boundaries (edges). Common boundary conditions include clamped (C), free (F) and simply support (SS), although others exist. For plinth duty, either C or SS are common. Each edge is considered, so that a panel (plate) may be only one of these, or a combination of two or all three. The results for C and SS will be very similar, FF will not.
Different turntable types may need different approaches, and audiophiles/music lovers may prefer different degrees of damping. Certainly one design fits all is not being suggested. I prefer very low colouration, so high damping for me, with idler drive turntables.
I have been trying out various Platter Mat Materials for a very long time.
The acquirement of Materials has evolved over time.
As the set up of my TT's evolved the owned Platter Mat Materials were revisited, to be used as a inteface within the new assembly of support materials.
It is of interest that one that is not so liked in one configuration or on a Drive can become more attractive for the role, as the environment changes.
The following is a recent report put on the Group Buy Thread on a Material I purchased recently and was comparing it to materials I believe work best on my DD TT, in my listening room.
______________________________________________________________
I would like to report a Update on the Usage of the 3mm and 5mm Forex Foam Platter Mats on my TT.
I don't know if the Slight Changes in the content of the report are a result of my New Phonostage becoming fully settled, or the MC Cartridge now Approaching about 300+ Hours of usage.
Or it could be the Honeymoon Period is over for the 3mm.
Recently I revisited a Comparison Exercise I had been carrying out with Platter Mats, using the Forex 3mm, Tenuto Gun Metal and AT-600 Ceramic.
The Sony Liquid Filled Rubber referred to in a previous post does not work so well on the used TT.
The 3mm is now Deemed as OK, and It offers the antithesis of the Tenuto
in terms of presentation, it allows the Perception of weight underpinning the Music and this is attractive, escpecially for the Blues Music I listen to.
The 3mm Forex as the comparisons continued were showing a smearing and loss of fine detail clarity when compared to the other two Platter Mat materials.
The 3mm was being used lesser as the weeks went on.
A few weeks ago I was putting the 3mm Forex back into the Supplied Tranportation Package and the 5mm was contained in the Package.
The 5mm had been completely overlooked since I gave one away as a Gift to another TT owner.
I have been following a Thread about adaptions to a Platter that is the same TT as my one in use, and the reports were that as the Acetal was produced in increased Thickness the Audible Improvements was more Noticeable.
I set off comparing the 3mm and 5mm and the improvement of the 5mm was instant, the clarity of the details was more reminding as the other Two Materials when in use.
The Weight and Authority underpinning the music remained.
The 3mm was removed and no longer used.
The Comaprisons started with the Three Materials, using a variety of longterm owned, recently cleaned, very well known LP's.
Across the Three Materials at this stage I am at a loss to pick a overall Best.
The Tenuto creates a Clarity and Lightness that is ethereal.
The AT-600 is close to the Tenuto but has a few extra Kilos on board to add a little Authority.
The 5mm Forex adds an extra dimension to the Authority and the Music is perceived as very present.
I cannot in any way find a way to say that the Attack , Dynamics, Decay and Micro Dynamics are compromised by any material in a more noticeable manner than another.
I am over the moon that for the very fair price asked for the Forex Mats in the Group Buy, that this has been the outcome discovered with the 5mm Thickness Mat, when finally being put to a Trial.
_____________________________________________________________
To put the above report into a little more context.
The 5mm Forex Foam Mat works better on the DD TT, than any Rubber Mats I have compared, and a Cork / Rubber compound.
The Gifted 5mm Forex Foam Mat, transformed the Belt Drive TT it was used on.
The TT owner was so glad to have been introduced to it, and the gift.
With the same TT Owner on another TT on a different occasion, when TT Footers and Mats were being compared, my Tenuto sounded the worst interface of the Mats being exchanged.
Another friend who is very keen for the Tenuto as the Sole Mat,
was pleasantly surprised by the impression the AT-600 made on their TT.
I do not know of a Science to the usage of Platter Mats, that makes one material seem the best option, using different materials in different environments can have a very noticeable effects for the better or worse.
The acquirement of Materials has evolved over time.
As the set up of my TT's evolved the owned Platter Mat Materials were revisited, to be used as a inteface within the new assembly of support materials.
It is of interest that one that is not so liked in one configuration or on a Drive can become more attractive for the role, as the environment changes.
The following is a recent report put on the Group Buy Thread on a Material I purchased recently and was comparing it to materials I believe work best on my DD TT, in my listening room.
______________________________________________________________
I would like to report a Update on the Usage of the 3mm and 5mm Forex Foam Platter Mats on my TT.
I don't know if the Slight Changes in the content of the report are a result of my New Phonostage becoming fully settled, or the MC Cartridge now Approaching about 300+ Hours of usage.
Or it could be the Honeymoon Period is over for the 3mm.
Recently I revisited a Comparison Exercise I had been carrying out with Platter Mats, using the Forex 3mm, Tenuto Gun Metal and AT-600 Ceramic.
The Sony Liquid Filled Rubber referred to in a previous post does not work so well on the used TT.
The 3mm is now Deemed as OK, and It offers the antithesis of the Tenuto
in terms of presentation, it allows the Perception of weight underpinning the Music and this is attractive, escpecially for the Blues Music I listen to.
The 3mm Forex as the comparisons continued were showing a smearing and loss of fine detail clarity when compared to the other two Platter Mat materials.
The 3mm was being used lesser as the weeks went on.
A few weeks ago I was putting the 3mm Forex back into the Supplied Tranportation Package and the 5mm was contained in the Package.
The 5mm had been completely overlooked since I gave one away as a Gift to another TT owner.
I have been following a Thread about adaptions to a Platter that is the same TT as my one in use, and the reports were that as the Acetal was produced in increased Thickness the Audible Improvements was more Noticeable.
I set off comparing the 3mm and 5mm and the improvement of the 5mm was instant, the clarity of the details was more reminding as the other Two Materials when in use.
The Weight and Authority underpinning the music remained.
The 3mm was removed and no longer used.
The Comaprisons started with the Three Materials, using a variety of longterm owned, recently cleaned, very well known LP's.
Across the Three Materials at this stage I am at a loss to pick a overall Best.
The Tenuto creates a Clarity and Lightness that is ethereal.
The AT-600 is close to the Tenuto but has a few extra Kilos on board to add a little Authority.
The 5mm Forex adds an extra dimension to the Authority and the Music is perceived as very present.
I cannot in any way find a way to say that the Attack , Dynamics, Decay and Micro Dynamics are compromised by any material in a more noticeable manner than another.
I am over the moon that for the very fair price asked for the Forex Mats in the Group Buy, that this has been the outcome discovered with the 5mm Thickness Mat, when finally being put to a Trial.
_____________________________________________________________
To put the above report into a little more context.
The 5mm Forex Foam Mat works better on the DD TT, than any Rubber Mats I have compared, and a Cork / Rubber compound.
The Gifted 5mm Forex Foam Mat, transformed the Belt Drive TT it was used on.
The TT owner was so glad to have been introduced to it, and the gift.
With the same TT Owner on another TT on a different occasion, when TT Footers and Mats were being compared, my Tenuto sounded the worst interface of the Mats being exchanged.
Another friend who is very keen for the Tenuto as the Sole Mat,
was pleasantly surprised by the impression the AT-600 made on their TT.
I do not know of a Science to the usage of Platter Mats, that makes one material seem the best option, using different materials in different environments can have a very noticeable effects for the better or worse.
Looks like some good materials in your post. It will keep me Googling for a while.
I have a couple of test records with frequency sweeps. I've wondered whether any of the Mats I've tried would show differences on those sweeps. Resolving to try it one day.
I'm not claiming it's better than what you've listed, but a buddy suggested a 2mm leather Mat to me. My fav so far. I like it on a glass Rega platter and an old Heybrook Aluminum platter.
Hugh
Hi Hugh
Each Individual has a unique preference for what they perceive as satisfying their requirement.
When the use of Materials for Plinths, Sub Plinths, Tonearm Bases , Footers,
and Platter Mats is being worked around.
My experiences in making the use of various materials available to others, has shown that the variances in the SQ will produce a variety of perceptions of the delivery where a Group are not unaminous in their assessments.
The demonstrations are not long, so the changes being perceived are noticeable between the Materials.
Some will prefer one material over another.
I do not personally know of a one Material is best for all outcome, when the Materials are being selected.
I use 20mm Thickness MU25 Plywood as a Plinth.
I chose to stay with MU25 for a extensive period because a Person I communicate with who has a quantity of Plinths produced for their own trials and Customers, has rejected P'holz after trials as their choice of Materials.
Additionally I am able to Listen to P'holz Plinths in anoother System, with the same TT and Tonearm and very similar Cartridge as mine.
I am always impressed by the TT and very much enjoy the Social Side of the experience.
I am not able to determine how much of a difference is being heard with the P'holz Plinth.
It is now getting closer to the Time when I produce the Plinth Material in Permali (1400Kg Cu Mtr)
This will then offer a good opportunity to determine how a Densified Birch Plywood compares to a Beech Plywood MU25 (750Kg Cu Mtr) that has received a compression that is increased, when compared to a commonly produced Birch Plywood (650Kg per Cu Mtr).
Each Individual has a unique preference for what they perceive as satisfying their requirement.
When the use of Materials for Plinths, Sub Plinths, Tonearm Bases , Footers,
and Platter Mats is being worked around.
My experiences in making the use of various materials available to others, has shown that the variances in the SQ will produce a variety of perceptions of the delivery where a Group are not unaminous in their assessments.
The demonstrations are not long, so the changes being perceived are noticeable between the Materials.
Some will prefer one material over another.
I do not personally know of a one Material is best for all outcome, when the Materials are being selected.
I use 20mm Thickness MU25 Plywood as a Plinth.
I chose to stay with MU25 for a extensive period because a Person I communicate with who has a quantity of Plinths produced for their own trials and Customers, has rejected P'holz after trials as their choice of Materials.
Additionally I am able to Listen to P'holz Plinths in anoother System, with the same TT and Tonearm and very similar Cartridge as mine.
I am always impressed by the TT and very much enjoy the Social Side of the experience.
I am not able to determine how much of a difference is being heard with the P'holz Plinth.
It is now getting closer to the Time when I produce the Plinth Material in Permali (1400Kg Cu Mtr)
This will then offer a good opportunity to determine how a Densified Birch Plywood compares to a Beech Plywood MU25 (750Kg Cu Mtr) that has received a compression that is increased, when compared to a commonly produced Birch Plywood (650Kg per Cu Mtr).
Studley,
One thing to be cautious about - Panzerholz is quite stiff. The panels tend to have some curvature, especially the thinner ones (8mm).
I cut a 19"x2" x 3/4" (20mm) piece down to 16mm thick. The remaining 2mm piece did not stay straight. Lots of stress in those layers I guess.
I'm thinking about making a platter later. Most likley I'll have to fasten smaller pieces together to get it flat.
Hugh