Isolation materials

[ack]

Does anyone have experience with the EAR ISODAMP C-1002 isolation compound, in various thicknesses? Any comparisons with sorbothane? I want to build on my existing custom TT isolation, and EAR is supposed to be the broad industry leader in isolation devices, from aircraft applications down to fine lab instrument, to which the C-1002 is supposed to apply...

Thanks

 

[garylkoh]

They would sound wonderful under a TT. Far better than sorbothane for various reasons.

However, this material has a problem - it gets oily with age and it marks cabinets and things. I wouldn't put it under a nice high-gloss loudspeaker for example.

View attachment 2459

This was another of my pre-Genesis days failed products. I sent Mark some of my spikes, but they failed for his application too

If you like, I can send you a few to try under your TT so that you don't waste time making any.

 

[ack]

Thanks for the offer... On top of the 4 feet I would also need a sheet for the external VPI motor. I have located some small sheets for $30, so let me pursue this first. I also want to try it under the marble shelf that the TT sits on... Thinking about 0.25" thickness...

Thanks for the info...

 

[garylkoh]

See my thread on loudspeaker coupling/decoupling. If you use Isodamp to decouple the vibrations of the external VPI motor, the vibrations generated by the motor has to have somewhere to go, and it may travel up the belt. You want to couple the motor to drain the vibrations away.

 

[ack]

Hmmmm, I thought Isodamp would convert vibrations to heat... it won't?

 

[garylkoh]

Yes it will, but you have to couple the motor tightly to the material. It is usually used as an interface layer on jet engine mountings - hence the requirement for strong pressure. It is used to absorb vibrations between one surface and the other surface so that the vibrations do not transmit from one side (the jet engine) to the other side (the aircraft frame).

With the pucks I made, you place a spike on one side (the material is hard enough that the spike doesn't damage it) and this prevents vibrations from going through the spike to the equipment rack. I thought that was your application - to isolate the TT from the rack, and the rack from the TT. You don't want motor vibrations to be transmitted to your rack where they may cause sonic degradation of the other components on the rack.

 

[fas42]

As a thought, you could try using Blu-Tack or equivalent to couple the device to the damping material. There are plenty of materials out there in the commercial world, with a huge mix of properties, which give tremendous scope for experimentation. It's all about stopping the audio components wobbling, every time you do something to minimise this it will be a win.

A winner for me and the friend has been a big sheet of premium viscoelastic mattress material, "memory foam". Get hold of the best quality you can, and play with it. As an example, a pad of it to support the friend's Quad CD, and Naim amp completely transformed the sound, in a positive sense.

Frank

 

[JackD201]

I'm with Gary on more coupling, less decoupling for motors. That motor shaft and pulley can not be allowed to wobble about which would happen on any pliable surface.

 

[ack]

Gary, this material is incredible - how come it didn't work for you? The pointy VPI feet sink into it and a lot of noise is gone... I have three layers of defense: 1) stillpoints plus C-1002 coupling a granite shelf to the rack; 2) C-1002 coupling the VPI feet to the granite; 3) C-1002 coupling the motor to the granite. Total weight is about 120lbs. Tapping in sequence first the VPI body, then the granite and finally the rack there is quite audible reduction with every step of at least 10dB. In addition, I hear transformer buzz leaking to the stand if I stick my ear on the rack, which is not present on the granite and obviously the TT... Finally, micro-vibrations felt before by touching the motor are also gone... I am going to use this material in my garage-opener.

Would a sandbox to rest the TT on be even better?

 

[garylkoh]

The material IS incredible. I didn't say that it didn't work - it's just that it gets oily with age, and it will mark things. I've got a lot of equipment with circular marks on the top, bottom, etc. It permanently marks almost every thing I put it on - even stainless steel. I literally have a hundred of these stainless steel pucks with Isodamp on both sides in various sizes that I still regularly use.

If your motor has spike feet, the spikes will sink into the material and it will couple. I thought that you were going to put a flat motor on top of a sheet of this, and the motor will "float". That will be decoupling the motor which I wouldn't advise. At RMAF, my turntable had these pucks under its feet, and I thought that the bass tightened up considerably.

I don't know about the sandbox. I think that the sand will compress in time, so you need to rake it periodically.

 

[Orb]

The material IS incredible. I didn't say that it didn't work - it's just that it gets oily with age, and it will mark things. I've got a lot of equipment with circular marks on the top, bottom, etc. It permanently marks almost every thing I put it on - even stainless steel. I literally have a hundred of these stainless steel pucks with Isodamp on both sides in various sizes that I still regularly use.

If your motor has spike feet, the spikes will sink into the material and it will couple. I thought that you were going to put a flat motor on top of a sheet of this, and the motor will "float". That will be decoupling the motor which I wouldn't advise. At RMAF, my turntable had these pucks under its feet, and I thought that the bass tightened up considerably.

I don't know about the sandbox. I think that the sand will compress in time, so you need to rake it periodically.

Silly question, why not use a very thin plastic/polymer type material sheet to stop the marking (not saying it would work but as an example plastic or vinyl wrap/clingfilm), or would this influence the behaviour?

Cheers
Orb

 

[ack]

@Orb - that's what I ended up doing...

 

[garylkoh]

Silly question, why not use a very thin plastic/polymer type material sheet to stop the marking (not saying it would work but as an example plastic or vinyl wrap/clingfilm), or would this influence the behaviour?

Cheers
Orb

If you are spiking into the material, the clingfilm makes no difference - but spiking into the material, the oily/marking property doesn't matter except that it collects dust and looks really horrible just a couple of months into its life. If you are using it as a puck under other equipment, the clingfilm makes it slippery and kinda defeats its horizontal coupling properties. I think that it may rely on its stickiness to couple to the surface of the device it is meant to help absorb vibration from.

But if you don't care for marking your gear with round dots, it is an awesome material.

 

[Orb]

Yeah understood, I just mentioned clingfilm to give an idea of what I meant, heck clingfilm is crud even for what it is meant to do at times
A more plausible material would possibly the vinyl wrap material they use on cars these days (think that is what it is called).
But I do not know if it would possibly influence the behaviour of the original puck product.
Ack, keep us informed how it goes.

Cheers
Orb

 

[fas42]

As another option, how about creating a very thin pad of Blu-Tack firmly mated to the gear, and then use the material coupled to the Blu-Tack? Of course, there may some chemical incompatibility between the Blu-Tack and other material, you need to set up a test connection and leave it for some months to see how it goes before trying in a big way ...

Or good old sticky tape: the "glue" in this is actually viscoelastic in nature.

Frank

 

[ack]

Yeah understood, I just mentioned clingfilm to give an idea of what I meant, heck clingfilm is crud even for what it is meant to do at times
A more plausible material would possibly the vinyl wrap material they use on cars these days (think that is what it is called).
But I do not know if it would possibly influence the behaviour of the original puck product.
Ack, keep us informed how it goes.

Cheers
Orb

All I did is place a large enough cut-out from a ziplock bag under the isodamp so as to protect the granite shelf. I let the steel vpi feet sink in it (it's not much anyway), so I don't care about them getting marked... We'll see how it goes in a few months. To be honest I have another crazy idea in the works... But I can't go into details right now... This is not exactly a sane hobby

 

[ack]

So here's what I came up with... interesting results - easily passes the knuckle rap test, foot stomping, the stethoscope test on the body and platter (and to a large extent on the motor body as well), and the silent track test on the HiFiNews test LP with the subwoofer on and at max volume. We need to productize this


Isodamp C-1002 & Stillpoints supporting the granite


Sorbothane hemisphere & Isodamp for the feet (notice the protective piece of sticky paper protecting the granite from the Isodamp)


Sorbothane sheet, Isodamp and cork plates for the motor

 

[Orb]

Great pictures on what you did.
And yeah the HifiNews test LP is very good.
For those in the UK; this test LP and also the Stereophile test CDs can be purchased from:
http://www.britishaudio.co.uk/
Used them in the past and great service.

Cheers
Orb

 

[hifistan]

I use some Star Sound small points under my external motor and that helped. They are brass, I don't know if they are still in business but they made some good things. Their brass cones were a screw out and screw in VPI replacement for the aluminum cones.

 

[hifistan]

I has just about the last Aries Extended that they had and of course the long arm. They may have reintroduces it by now, I have been out of touch for some time. Sounded very good but a bear to move and as I could only set up one table at a time I sold it to a friend. I was a VPI dealer then and they were easy to set up and sounded very good. After I stopped being a dealer I got an LP12 that a friend had abandon for CD. Not easy to set up but a lot lighter.