Vibration Isolation / Support for Glass

Stillpoints: I don’t know because they’re very careful not to show pictures of the ceramic balls!
(The older products looked as though they were probably using alumina.)

Finite elemente appear to be using either silicon carbide or silicon nitride (but I can’t be sure)

I don’t seem to be able to find much about Franz audio.

You might have to buy one and cut it in half for us @frenchrooster :stuck_out_tongue_winking_eye::+1:


Franc audio ceramic disc.
You have a review on 6 moons audio. com

If you find the special saw to cut ceramic, I will do that :sunglasses:. Good luck :crazy_face:


With laser?

Thank you, they look as though they’re possibly alumina.

Can it be delrin?

No need for a laser, all you need is a small diamond abrasion saw - you can easily get one that fits a ‘Dremel’ style rotary tool.

It must cost a lot, not?

No, as Delrin (a trade name for polyacetal) is a polymer not a ceramic.

1 Like

I think they’re about £10 / €11 (I think they’re only about 25mm diameter by about 0.7mm thick).

And the ceramic platter of Rega p10? Not the same probably as Stillpoints because much less expensive. Perhaps 1k for all the platter.

“The platter is produced from ceramic oxide powder…”

Taking that statement from Rega, looking at it and thinking about appropriate materials, I think sintered alumina is the most likely ceramic material for the platter (alumina is aluminium oxide). (However boron nitride is also a possibility, but on cost grounds it would surprise me if this was the case.)

1 Like

You can cut your fancy Ethernet cables in half at the same time and see what’s inside them apart from snake oil :joy::joy::joy:

1 Like

You have eaten your hat once Mike. I guess you will eat one more piece later , the day you will discover what a good ethernet cable can bring.


I just landed a second hand Chord Signature ARAY cable!

1 Like

I am impatient to read you when it will be connected!

1 Like

Hi Xanthe, I’m curious, is the brass surface completely flat, with the little black thing there to stop the ball from rolling around?

Interesting way of limiting vibration transmission. And straightforward to to build.

Silicon nitride is indeed an excellent choice as it is extremely hard.

It would be interesting to try lead instead of brass, for its ductility properties.

Are you planning to test your system, make some measurements?

You spotted it!
It’s not flat, there’s a very small, shallow, polished depression in the middle that centres the ball in normal operation. The cage is normally quite loose. To prevent this being a problem it’s made for a material that has some limited self damping characteristics and is very light weighing 0.33g.

The brass had to be locally hardened to deal with the contact pressure from the silicon nitride ball, so using lead (or tin) would be possible but would leave it open to transmitting more transverse vibration.
Additional differences are that
1 the lower sound velocity in lead would be beneficial in increasing energy reflection.
2 the increased contact area at the lower interface would increase energy transmission.

Unfortunately I don’t have the necessary high speed laser interferometer to really analyse the system (I don’t think the accelerometers in my’phone would be sufficiently sensitive to measure the overall effect either).