D.I.Y. Mat.

[Mr Kipling]

Anyone experimented with a diy mat comprising of 2 compliant sheets sandwiching a gel substance or fine sand?

[bobbasrah]

Anyone experimented with a diy mat comprising of 2 compliant sheets sandwiching a gel substance or fine sand?

MacDonalds ?:eyebrows:

[Mr Kipling]

MacDonalds ?:eyebrows:

Bob. . . I thought I was going to get a serious reply there!

Are you a native? Somehow I don't think so.

[bobbasrah]

Bob. . . I thought I was going to get a serious reply there!

Are you a native? Somehow I don't think so.

Serious, moi? Played around with so many different DIY mat variations with everything from suede to a glass ring, weird to ridiculous, and most fun I had was with the glass on blutac and a London Gold... Long time since I played vinyl to be honest... and not sure what sand or gel will do in a sandwich to the sonics, but what is the harm in experimenting....

Sorry to disappoint you but afraid I am native from Scotlandshire, that forgotten bit up north, but do a lot of overseas work, currently far down south next to the sunny med.... Sounds more exotic than it is unless you are in Thurso...

[Mr Kipling]

Serious, moi? Played around with so many different DIY mat variations with everything from suede to a glass ring, weird to ridiculous, and most fun I had was with the glass on blutac and a London Gold... Long time since I played vinyl to be honest... and not sure what sand or gel will do in a sandwich to the sonics, but what is the harm in experimenting....

Sorry to disappoint you but afraid I am native from Scotlandshire, that forgotten bit up north, but do a lot of overseas work, currently far down south next to the sunny med.... Sounds more exotic than it is unless you are in Thurso...

Well, thanks for the enlightenment Bob.

Always been a bit of a question mark above your name (Who was that masked man Bobbasrah? Hi-Ho Silver! Awwaayyyy!!. . . )

Bit wiser now.

[bobbasrah]

Well, thanks for the enlightenment Bob.

Always been a bit of a question mark above your name (Who was that masked man Bobbasrah? Hi-Ho Silver! Awwaayyyy!!. . . )

Bit wiser now.

The Hi-Ho Silver Away sounds about right, a combination of the aging process and stress, or tired follicles.....
Good luck with the Big Mac Mat....:D

[synsei]

If your experiment works Stephen and you decide to take it to market, may I suggest you call it the McMat? :D

[walpurgis]

Anyone experimented with a diy mat comprising of 2 compliant sheets sandwiching a gel substance or fine sand?

Two compliant sheets of what? And what is the intended purpose of the gel or granular filler, just to provide an interface, or damping?

Composite mats are not necessarily the way to go. A single layer of material with good internal damping would be my choice. Butyl Rubber, Polyurethane or Sorbothane. Unfortunately, Sorbothane tends to weep an oily substance which contaminates records, as I've found out to my cost. I'd have a bash at using soft Polyurethane sheet myself.

[Mr Kipling]

Two compliant sheets of what? And what is the intended purpose of the gel or granular filler, just to provide an interface, or damping?

Composite mats are not necessarily the way to go. A single layer of material with good internal damping would be my choice. Butyl Rubber, Polyurethane or Sorbothane. Unfortunately, Sorbothane tends to weep an oily substance which contaminates records, as I've found out to my cost. I'd have a bash at using soft Polyurethane sheet myself.
The idea of the gel and sand would be to provide an effective interface with a disc (assuming it's flat) and also provide damping at the same time. I was thinking of 2 polyurethane sheets with a hard centre section with an o-ring section surrounding it slightly higher for the label and another o-ring section just short of the lp edge with a gel injected or sand poured between the sheets. Getting the sand level would be a tad tricky and perhaps best done by being vibrated.

Just an idea. I get them now and again. Not as often as I used to.

[Stubies]

Anyone experimented with a diy mat comprising of 2 compliant sheets sandwiching a gel substance or fine sand?

Have you seen those washing machine vibration mats? they probably isolate very well - cost about 15 GBP at the hardware store, and can be cut to any size you like

Would that work?

[walpurgis]

The idea of the gel and sand would be to provide an effective interface with a disc (assuming it's flat) and also provide damping at the same time. I was thinking of 2 polyurethane sheets with a hard centre section with an o-ring section surrounding it slightly higher for the label and another o-ring section just short of the lp edge with a gel injected or sand poured between the sheets. Getting the sand level would be a tad tricky and perhaps best done by being vibrated.

Just an idea. I get them now and again. Not as often as I used to.

Seriously, experimenting with polyurethane may be a good idea, but the composite construction idea just sounds like extra work for no return. Not to mention the reliability. Bonded layers tend to come apart. Also, sand is a great damping material, like most small particle hard materials. But, only when it's loose.

By the way, you would not get the sand level by vibrating. Whatever surface you had it on would produce vibration modes and the sand would follow these. Screeding is about the best way.

Unless the sand particles were in contact with each other in whatever medium they are bonded into the mat sandwich with, they will provide no damping and just act as a filler. Aggregate granules like sand can interlock mechanically together. That's what gives bituminous macadam (tarmac) its strength.

And yes, I've studied materials and engineering in general for a living and as an interest.

[Mr Kipling]

Thanks Geoff. Didn't really think the sand was all that practical, but worth a try; also thought about flour, as in baking.

[walpurgis]

Thanks Geoff. Didn't really think the sand was all that practical, but worth a try; also thought about flour, as in baking.

I don't think it would taste too good. :)

[guy]

Hi,

I'm not entirely convinced that damping the record is what is needed.

These are assuptions (based on a limited number of observations). However,
I assume that heavy weight pressings have more inherent damping than lighterweight - but, I find that many of my heavyweight audiophile pressings are not as dynamic as standard weight early (A1/2 etc) pressings.

The early Rega rubber mat (radial ribbed - ooh er missus!) seemed to be quite adequate to me - I didn't hear any great improvement when I traded up to the felt mat in the seventies, although I put that down to not having a very expensive system. After all if all the experts said it was better surely it must be.

I now use a Plattamat on my LP12 in preference to the Linn felt. I hade a lot of abuse for this on other forums, but sod it, I like it so it is better for me. Worth noting though that the plattamat has less contact area than the felt.

I have wondered whether no support for the record (other than at the centre label) is the way to go. Ringmat seems to be well thought of and that only supports a very small area of the disc.

Sorry, not meant as a thread crap as I do think than the support of vinyl needs more investigation and that damped support across the whole surface may be the wrong way to go.

Best wishes. Guy.

[Mr Kipling]

I'm not expecting to be catapulted into audio nivana, Guy; I'm just curious.

Regarding going platter-less, Ed Meitner, a designer of some repute, produced one in the '80s. Quite minimalist all round having a solid plinth and unipivot arm.

The other idea which only Oracle used, I think, is stress-loading the lp with a screw-down piece and a radiused section under the lp. A diy feature showing how it could be with a LP12 was shown in Hi-Fi News & RR in the '80s. It does entail welding a threaded section to the spindle.

[YNWaN]

I use a mat that supports the record over only a very minimal area. I have experimented extensively with mats, both trying those made by others and making my own. In general, I have found that those mats that seek to damp the record are the worst; whilst they are very effective (or can be) at damping some frequencies they are never linear across the entire frequency range and so introduce significant colourations of their own.