Speakers and Turntables Made With MDF

MDF synergy...............oh dear God help us all. :P

MDF is cheap and dimensionally stable, other than that I don't think it has any magical properties or should I say truly desirable qualities.

I do not go out of my way to avoid it however.

I have done comparable listening tests to various materials under my turntable, preamp and loudspeakers.

In general materials sound like what they look and feel like.

Wood is woody.

Glass is clear but with some glare, so on and so forth.

Composite materials in general suck the life out, this includes MDF, Corian and composite grinding wheels but sometimes you want just a little excess energy sucked out so use in careful measure.

If you think of your sound system as a musical instrument with sympathetic resonances, then material selection is paramount. Brass is by far my favorite material to tune my system with.


How 7 Different Woods Affect Your Acoustic Sound
(from Fender dot com)
You see it all the time when shopping for an acoustic guitar: Sitka spruce top, mahogany back and sides, rosewood bridge, this wood, that wood, another wood. All very impressive, but what does it mean? Most of us aren’t wood experts, so what exactly do different woods have to do with the sound of an acoustic guitar?


A great deal, actually. The woods used to build guitars—acoustic guitars in particular—are called tonewoods, and they have enormous effects on the sound and price of an instrument. Various woods have distinct sound qualities, especially when used for the top of an acoustic guitar, which is the most important wooden tonal element of the instrument.


You’re not going to be tested, but here are the ABCs of tonewoods — various woods and the sound qualities they’re noted for:
 
Thanks kach22i....I wonder why the mega buck speakers and turntables would use MDF? It appears there are much better alternatives.

I am not sure what you define as "mega buck".

A local store here actually carries "mega buck", one piece items +$20,000 and you see a lot of carbon fiber, cast and extruded aluminum, Hi-Tech plastics, composites, lamination of different materials, and exotic hardwoods.

Again if you think $7,000 MDF loudspeaker is mega buck, then what adjective applies to $70,000 speakers?
 
Could you give examples of “mega buck speakers” that use MDF. I need to know who to avoid.

I cant's at the moment. Maybe I shouldn't have included speakers as I'm not sure of the present day materials. I do know in the past MDF was used. However I have a VPI-HRX turntable that is 3 layers of MDF/aluminum/MDF at I believe the MSRP is $15,000.
 
Could you give examples of “mega buck speakers” that use MDF. I need to know who to avoid.
Your MAGICO's qualify as MDF free I believe, so you are safe, lots of aluminum.


MAGICO
Enclosures


No singular material can satisfy all of the properties desirable in a loudspeaker enclosure.


As stiffness increases, moving from MDF to phenolic resin to aluminum, cabinet vibrations are drastically reduced, although a sharpened Q of the resonance results in an audible ring.


By damping the high Q resonance via elaborate constrained layer damping we have eliminated all energy storage and audible resonance from our enclosure.
 
I cant's at the moment. Maybe I shouldn't have included speakers as I'm not sure of the present day materials. I do know in the past MDF was used. However I have a VPI-HRX turntable that is 3 layers of MDF/aluminum/MDF at I believe the MSRP is $15,000.
VPI likes to call their plinth a chassis, and in that model it looks to be (Acrylic-Aluminum-Acrylic) composite layer.

Some of VPI's lower cost models are MDF I believe, it has excellent dampening qualities, too much in some cases and can sound rather dead (a common criticism of VPI).

AVID has a line of turntables all using the same metal cast chassis/plinth, not sure if its aluminum, magnesium or gray metal used in brake rotors. In any case they differ in price mostly in the platter. The bottom of the line is a MDF platter that has gotten some good reviews. Anyway, as you step up in price you go to acrylic platters, aluminum, aluminum with copper and brass and all sorts of laminations to control resonances.

MDF is a one material solution that leans to the dead side but can be sandwiched.
 
VPI likes to call their plinth a chassis, and in that model it looks to be (Acrylic-Aluminum-Acrylic) composite layer.

Some of VPI's lower cost models are MDF I believe, it has excellent dampening qualities, too much in some cases and can sound rather dead (a common criticism of VPI).

AVID has a line of turntables all using the same metal cast chassis/plinth, not sure if its aluminum, magnesium or gray metal used in brake rotors. In any case they differ in price mostly in the platter. The bottom of the line is a MDF platter that has gotten some good reviews. Anyway, as you step up in price you go to acrylic platters, aluminum, aluminum with copper and brass and all sorts of laminations to control resonances.

MDF is a one material solution that leans to the dead side but can be sandwiched.

Thanks kach22i for the detailed explanation. It appears I should have done a bit more research before my post. :blush:
 
Thanks kach22i for the detailed explanation. It appears I should have done a bit more research before my post. :blush:
People that already know everything can be boring, I found my way here to teach and learn.

That is hard to do when everyone is a real and actual expert.

I only pretend to be.:D

EDIT:


MDF can be part of a speaker system or TT, I do not want to imply otherwise - just use with caution and be aware of it's properties, both good (if utilized) and bad (if ignored).

Examples:

https://www.audiocircle.com/index.php?topic=109265.0
Speaker Design: The VR5 Anniversary Mark 2’s use a four-layer triple chambered hybrid transmission line cabinet. The innermost layer is ½ inch marble, then a special acoustic damping adhesive layer bonded to thick high-density MDF and beautifully finished with an African Hazelwood veneer.

[h=1]Von Schweikert Audio VR5 Anniversary MK2 ORIGINAL NOT UPGRADED MINT [Expired]
https://www.audiogon.com/listings/full-range-von-schweikert-audio-vr5-anniversary-mk2-original-not-upgraded-mint-2015-12-18-speakers-l4l-8a3
Cabinet and Bracing: A two-inch thick front baffle provides exceptional vibration control and image solidity, while MDF interlocking braces provide rigidity and freedom from boxy colorations.
[/h]
 
MDF synergy...............oh dear God help us all. :P

MDF is cheap and dimensionally stable, other than that I don't think it has any magical properties or should I say truly desirable qualities.

I do not go out of my way to avoid it however.

I have done comparable listening tests to various materials under my turntable, preamp and loudspeakers.

In general materials sound like what they look and feel like.

Wood is woody.

Glass is clear but with some glare, so on and so forth.

Composite materials in general suck the life out, this includes MDF, Corian and composite grinding wheels but sometimes you want just a little excess energy sucked out so use in careful measure.

If you think of your sound system as a musical instrument with sympathetic resonances, then material selection is paramount. Brass is by far my favorite material to tune my system with.


How 7 Different Woods Affect Your Acoustic Sound
(from Fender dot com)

If materials sound the way they look , Does your observation change when you cant visually see what material is being used ... :)
 
If materials sound the way they look , Does your observation change when you cant visually see what material is being used ... :)
I was surprised the other day when a very hi-end turntable I've heard was discovered to have a top coat of glass or glass composite as a final top layer of a platter over Dural aluminum.

Certainly there are layered affects I have not experimented with, and certain materials I just did not consider.

For instance 40 mm braced Hpl.


One of the more interesting platters I've read about is made from an unexpected material.

From the comments section:
https://www.analogplanet.com/conten...ible-turntable—motor-city-metal-machine-magic
default_user_85x85.jpg


Cast iron base Submitted by schiele on Sun, 2012-07-01 14:48


No doubt one of the reasons the Anvil performs so well for its price is the designer's selection of inexpensive gray iron for the base. Gray iron is actually a composite of iron and graphite flakes. The impedance mismatch between these two materials dissipates vibration very effectively. Gray iron's damping capacity is literally hundreds of times better than steel or aluminum. Traditionally the material of choice for exhaust manifolds and brake rotors because of its ability to suppress NVH ( noise vibration and harshness) it has lost market share in recent years due to its weight. It is still the best material for precision machine tool bases. It is puzzling that no company before Anvil has been knowledgeable enough to recognize the suitability of this material for turntables.

As you can see in the link below Gray Iron is far superior to aluminum in dampening.

http://www.atlasfdry.com/grayiron-damping.htm
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If anyone has a chart they find comparing commonly used materials in the making of turntables and loudspeakers regarding Mechanical Properties - Damping Capacity, please post it.

I would like to see how some plastics (acrylic + carbon fiber) and MDF stand up to the metals in the chart I've already posted.

I'm finding stuff, but not in the same units of measure.

I would also like to see where Brass/Bronze and Stainless Steel rank, and also glass/tempered + glass/laminated.


EDIT:

Found this PDF on Silicon Bronze Alloys for Music Applications.
https://www.google.com/url?sa=i&url...ved=0CAkQjhxqFwoTCKDL-YGK3OcCFQAAAAAdAAAAABAK
 
I found a article by Mike VansEvers many moons back on tone and tuning. Just did a search and came up with a link to the first part of it

https://positive-feedback.com/pfbackissues/0705/vansevers.7n5.html
I read about half of this yesterday (thank you for finding and posting it Mike B), and it goes way beyond my simple observations 10 years ago.

I like the comparison to room modes and the across the band frequency distribution verses the bundling or bunching up of frequencies that can have some unpleasant consequences.

I believe some manufactures are more aware of these resonance phenomena than others.

For instance my McIntosh CD player seemed immune to my experiments, while other equipment was very sensitive.

Perhaps a more obvious example would be the Brinkmann Balance turntable (not on my rack sadly) with custom platform to sit on.

https://www.stereophile.com/content/brinkmann-balance-turntable2
Because the Balance doesn't have a suspension, Blair suggests using a Harmonic Resolution Systems HRS M3 isolation base ($2200), which is custom-designed for the Balance and features a split granite platform to isolate the motor from the platter/bearing assembly.

I suppose outboard power supplies on just about anything can fall into the consideration of a resonance category.

Perhaps this topic is more mainstream than I initially assumed.






 
Good Audio is about the careful managing of resonances and not the total elimination of them. To do so will lead to what most describe as an unnatural HiFi sound, IMO ..



Regards
 
Anyone interested in reading PART-2 of the Mike VansEvers article click below (page 3) and scroll 2/3rds of the way down to:

The Stereo Times
http://www.stereotimes.com/comm0600.shtml
Tone Balancing the Bass Response of the System


Overview


"The whole is greater than the sum of its parts" is a phrase that can be used to describe an in-tune audio system's bass response.

It is important to note that our focus is the bass response of the system, rather than the bass of any one component. This is called a "systems approach". Even though we will be working with only one component at a time, we are interested only in how well its bass integrates with the bass of the SYSTEM. Individual components by themselves cannot make sound, much less music...................

If you want to read the article from the beginning, go to page one and read all four pages.

I found the link via Audio Asylum FYI.

And yes this part of the article quickly mentions MDF as being able to tame highs that are brash or annoying.
 
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