Isolation

Hi me again

I have had a look at several isolation platforms acylic granite ETC

I currently have my Turntable (Pro-Ject Classic Comfort) on a Slab of marble (Pre Amp and Turntable) Is it worth me going for Extra isolation above the Marble one of the Double layered Acrylic platforms? Sadly i haven't enough room for wall mounts.

I have ordered Russ Andrews Oak feet for the rest of my gear.

 

In my experience ,yes.

Try, though, to use a much diy stuff as you can to keep costs down.

Almost as we speak, I have used an 18mm ball bearing in a 20mil nut....to good effect.

 

The best way to determine how well your TT is rejecting airborne and structure-borne feedback is to measure it. This is very easy to do with the aid of a recording device, preferably a PC line input but any audio recorder will do.
You simply plug the output of the phono stage into the PC line input and start recording using something like Audacity (a free download). Place the pickup onto a stationary record and then play another source through your system a few db higher than you would usually listen.

Start the recording and watch the waveform on screen.
Using this method your TT is effectively being driven by both the support on which it rests and the sound travelling through the air in the room. You can magnify the on screen waveform for better results.

Using this method, experiment real time with different types of isolation/coupling/placement and listen to/observe the results.

This method will tell you exactly what you are doing and what is happening, not what you think might be happening.

 

a siple slab of marble wil not be providing any isolation .....

it will act as an energy sink ...ie you need to put more vibrational energy in to make it move .....

add some complient layer or feet to this slab and you will increase its effectiveness several times over ...

as the word isolation implies ...you need to cut the link between your tt and the support on which it sits ...

davef has done a great deal of experimentation in this field ...and has some interesting ideas if asked !

the project tt has a solid plinth ...this effectively going down the energy sink route ....as its the cheapest method to reduce vibration at the stylus groove interface ....you could look at t any number of things to reduce structure bourn vibration ....

look at the feet of the tt suport your using ....if they are spiked ...then they are coupling the support to the floor ..if you try to isolate these ..you will be interfereing in the original design concept . I'd suggest that any isolation activites be left to the support tt interface ...

one thig that I've found very effective is a sand box ...go and look at the one on the tnt hifi web site ..you could use the marble slab as the floating plate too...

 

Hi Rob,

Some great ideas here.

Chris I'd be fascinated to hear any results from this.