Question about acrylic vs. glass turntable platters

[JBColeman]

Hello--

I've got a Music Hall MMF-5 turntable, and I'm looking for opinions on
the advisability of buying an acrylic platter to replace the included
glass one. Would this give me a sonic upgrade? Is it worth the
investment? Thanks in advance--

JB Coleman

[Jenn]

In article . com>,
"JBColeman" > wrote:

> Hello--
>
> I've got a Music Hall MMF-5 turntable, and I'm looking for opinions on
> the advisability of buying an acrylic platter to replace the included
> glass one. Would this give me a sonic upgrade? Is it worth the
> investment? Thanks in advance--
>
> JB Coleman

Impossible to say without listening to each, IMO. I've had TTs with
each kind of platter and they both sounded great. In the case of glass,
I used it with a soft rubber mat (Oracle) and it was great. The Music
Hall has a felt mat, right? Sorry, I don't know how that sounds. The
whole system must work together, so you really must hear both on the TT
to decide.

[JBColeman]

Hello--

Yes, the MMF-5 comes with a felt mat. The glass produces a slightly
"hard" sort of sound, though, not unlike a metal platter. I was just
wondering if, in general, acrylic is less resonant than glass (as you
can tell, I've never heard a turntable with an acrylic platter). I'll
take up your suggestion about the rubber mat. Thanks,

JB Coleman

Jenn wrote:
> In article . com>,
> "JBColeman" > wrote:
>
> > Hello--
> >
> > I've got a Music Hall MMF-5 turntable, and I'm looking for opinions on
> > the advisability of buying an acrylic platter to replace the included
> > glass one. Would this give me a sonic upgrade? Is it worth the
> > investment? Thanks in advance--
> >
> > JB Coleman
>
> Impossible to say without listening to each, IMO. I've had TTs with
> each kind of platter and they both sounded great. In the case of glass,
> I used it with a soft rubber mat (Oracle) and it was great. The Music
> Hall has a felt mat, right? Sorry, I don't know how that sounds. The
> whole system must work together, so you really must hear both on the TT
> to decide.

[GregS]

In article om>, "JBColeman" > wrote:
>Hello--
>
>Yes, the MMF-5 comes with a felt mat. The glass produces a slightly
>"hard" sort of sound, though, not unlike a metal platter. I was just
>wondering if, in general, acrylic is less resonant than glass (as you
>can tell, I've never heard a turntable with an acrylic platter). I'll
>take up your suggestion about the rubber mat. Thanks,

Some say its best to match materials so sound can flow from one to another.
I guess you do need damping in conjunction with other materials.
You are using a record clamp, right?

greg


>
>Jenn wrote:
>> In article . com>,
>> "JBColeman" > wrote:
>>
>> > Hello--
>> >
>> > I've got a Music Hall MMF-5 turntable, and I'm looking for opinions on
>> > the advisability of buying an acrylic platter to replace the included
>> > glass one. Would this give me a sonic upgrade? Is it worth the
>> > investment? Thanks in advance--
>> >
>> > JB Coleman
>>
>> Impossible to say without listening to each, IMO. I've had TTs with
>> each kind of platter and they both sounded great. In the case of glass,
>> I used it with a soft rubber mat (Oracle) and it was great. The Music
>> Hall has a felt mat, right? Sorry, I don't know how that sounds. The
>> whole system must work together, so you really must hear both on the TT
>> to decide.
>

[Jenn]

In article om>,
"JBColeman" > wrote:

> Hello--
>
> Yes, the MMF-5 comes with a felt mat. The glass produces a slightly
> "hard" sort of sound, though, not unlike a metal platter. I was just
> wondering if, in general, acrylic is less resonant than glass (as you
> can tell, I've never heard a turntable with an acrylic platter).

I believe that it is, but I can't say for sure. I CAN tell you that the
acrylic platter on my TT (Clearaudio) seems very dead; much more so than
the metal one on my old TT.

> I'll
> take up your suggestion about the rubber mat.

The ones that seems to work best on glass platters are of the "gooey"
variety, i.e. PlatterMatter, etc.

> Thanks,
>
> JB Coleman
>
> Jenn wrote:
> > In article . com>,
> > "JBColeman" > wrote:
> >
> > > Hello--
> > >
> > > I've got a Music Hall MMF-5 turntable, and I'm looking for opinions on
> > > the advisability of buying an acrylic platter to replace the included
> > > glass one. Would this give me a sonic upgrade? Is it worth the
> > > investment? Thanks in advance--
> > >
> > > JB Coleman
> >
> > Impossible to say without listening to each, IMO. I've had TTs with
> > each kind of platter and they both sounded great. In the case of glass,
> > I used it with a soft rubber mat (Oracle) and it was great. The Music
> > Hall has a felt mat, right? Sorry, I don't know how that sounds. The
> > whole system must work together, so you really must hear both on the TT
> > to decide.

[Sander deWaal]

Jenn > said:

>In article om>,
> "JBColeman" > wrote:


>> Yes, the MMF-5 comes with a felt mat. The glass produces a slightly
>> "hard" sort of sound, though, not unlike a metal platter. I was just
>> wondering if, in general, acrylic is less resonant than glass (as you
>> can tell, I've never heard a turntable with an acrylic platter).


>I believe that it is, but I can't say for sure. I CAN tell you that the
>acrylic platter on my TT (Clearaudio) seems very dead; much more so than
>the metal one on my old TT.


I once used an acryllic mat.
It was the best sounding mat I've ever had in combination with my
turntable and arm/cart combo, but I replaced it with a combination of
felt/cork, because of the fact that dust and particles were forced
into the grooves of my records.

The acryllic mat doesn't as much absorb resonances in the LP itself,
but it transduces them into the platter mass.
Arm/cart resonance (should be somewhere around 10 Hz) are attenuated
that way, better than absorbed with rubber or even felt.

However, the cork/felt homebrew combo does this almost as well,
depending on the damping of your arm.

My turntable has a suspended subchassis though, with a resonance
frequency of a few Hz at most (outside the range of the arm
resonance!).
It may turn out that on turntables without a subchassis, and
pronounced arm resonance, the acryllic mat will be much better.


Tuning a turntable is all about resonances, and the careful
damping/draining of them.
Remember that vibrations that you can't even detect, can be of the
order of magnitude of the stylus movement, so good vibration
management is of the highest priority.

So, just try, and don't be afraid to make something yourself.
A cork mat can be made for less than $5.........and you can experiment
with the thickness of the layer and the combination with felt or
velvet.

--

- Never argue with idiots, they drag you down their level and beat you with experience. -

[Kalman Rubinson]

On Tue, 11 Apr 2006 23:22:08 +0200, Sander deWaal >
wrote:
>The acryllic mat doesn't as much absorb resonances in the LP itself,
>but it transduces them into the platter mass.

I know you don't mean this. I suspect you mean that it transfers the
energy to the platter mass. If it transduced it into the platter
mass, your platter would increase in mass continuously. ;-)

Kal

[JBColeman]

Thanks for your feedback--I might give the acrylic platter a try.
Thanks again,

JB Coleman

[Arny Krueger]

"JBColeman" > wrote in message
oups.com
> Hello--
>
> I've got a Music Hall MMF-5 turntable, and I'm looking
> for opinions on the advisability of buying an acrylic
> platter to replace the included glass one. Would this
> give me a sonic upgrade? Is it worth the investment?

Glass has a lot more weight for a given volume than plastic.

Does the plastic platter weigh as much as the glass one? If it does, then it
is probably thicker and will upset cartridge alignment, possibly in ways
that can't be compensated for. If it doesn't, then the reduced mass will
reduce the desired flywheel effect and change the tuning of the suspension.

Your best bet to improve damping is to get a mat that is made of a "dead"
material like Sorbothane.

[Sander deWaal]

Kalman Rubinson > said:

>On Tue, 11 Apr 2006 23:22:08 +0200, Sander deWaal >
>wrote:
>>The acryllic mat doesn't as much absorb resonances in the LP itself,
>>but it transduces them into the platter mass.
>
>I know you don't mean this. I suspect you mean that it transfers the
>energy to the platter mass. If it transduced it into the platter
>mass, your platter would increase in mass continuously. ;-)


Yup, poor choice of words, it was late and I was tired.

--

- Never argue with idiots, they drag you down their level and beat you with experience. -

[Sander deWaal]

"Arny Krueger" > said:


>> I've got a Music Hall MMF-5 turntable, and I'm looking
>> for opinions on the advisability of buying an acrylic
>> platter to replace the included glass one. Would this
>> give me a sonic upgrade? Is it worth the investment?


>Glass has a lot more weight for a given volume than plastic.

>Does the plastic platter weigh as much as the glass one? If it does, then it
>is probably thicker and will upset cartridge alignment, possibly in ways
>that can't be compensated for. If it doesn't, then the reduced mass will
>reduce the desired flywheel effect and change the tuning of the suspension.



That's indeed something to keep in mind.
My acrylic mat was about 5 mm thick, and replaced the stock rubber mat
that was on the platter.
The slight increase in VTA was easily corrected by lifting the arm
just a tad.


>Your best bet to improve damping is to get a mat that is made of a "dead"
>material like Sorbothane.


That's worth a try as well.

--

- Never argue with idiots, they drag you down their level and beat you with experience. -