Vibration Isolation / Support for Glass

Please don’t use a hammer to hit another hammer. Hammer faces are hardened and a sliver can fly off.

There’s a potential flaw in that approach, the ball pien is unlikely to be smooth enough to allow the ceramic ball to move freely in the recess produced, hence it will be vulnerable to ‘micro-rattle’. You’re going to have a lot of polishing to do.

The reason for using a hard steel ball bearing and a jig was to ensure a consistently smooth surface of known radius in which the ceramic ball can roll. The reason for using impact to form the indentation was to also obtain consistency (consistent height of a standardised weight gives consistent potential energy, gravity turns this into a consistent kinetic energy on a know vector, which in turn, when applied through a standardised former causes consistent deformation of a standardised material held perpendicular to the vector). In other words if everything is consistent and you hit it consistently, you get consistent results!

This is a fascinating read and thanks to @Xanthe and others for sharing your knowledge, method and observations.

I’m going to have a go at this and try a couple of shelves. It will be very interesting to see how it works in my set up.

I have pondered how to improve my TV cabinet from an audio perspective as it was a noticeable downgrade when my basic Atacama rack was sent packing. My thoughts had previously centred around rebuilding or adding to the inside of the cabinet with some, as isolated as possible, bamboo shelves but understanding a bit more about the principles of how the Fraim work from this post I think this will probably be more effective (and probably in keeping with the designs of the equipment) and much easier to achieve too :grinning:

I currently have an very old Mission Isoplat (sorbathane feet) under the 250 and a more recent Quadraspire Soundstage under the 272 which I cant say from memory made any vast difference but it’s a while since I’ve tried with and without and other things have changed since then too, so the comparison will be interesting. Fingers crossed I get back a bit of the magic that left with the old rack (although system was olive 72/250 back then).

It will be interesting to try for the LP12 also as I feel sure I can do better here too. I did originally get the Soundstage to try with it but while it was different it didn’t seem to suit. I did discuss a getting a Tramolin based on the LP12 being on a very heavy piece of furniture but my well know dealer seemed not to moved by the idea, even though he could have quite easily flogged me one. If anyone has any experience to add my my kind of set up I’d love to hear it. Wall shelves, proper racks and additional furniture are out I’m afraid.

Thanks again for the knowledge share

Adrian

You have a much greater problem than will be solved by glass sub-shelves no matter what isolation system you use: your components are on/in a large highly resonant box!

You really need to completely mechanically decouple the shelves from the main structure of the box. I suggest building ‘mini racks’ inside the main box with their feet going through holes in the bottom of the TV unit; the shelves and uprights of these mini racks should not touch the main structure of the TV unit. You’ll then need to work out a way of suspending the cables behind the the TV unit so they don’t touch the back of the unit (and preferably not the the walls or floor either of the room either)

Yes, I fear as much, but my options are limited. I hope it will be worth a punt though and maybe I will get lucky and find a modest gain, if nothing else the philosophy seems better suited to the equipment. And worst case it will look a bit neater.

It’s an interesting idea to build something that sits on the floor through the base of the cabinet, I will have a think about that.

Every time I’ve pondered about this cabinet in any detail I have come to the conclusion I probably need to start from scratch and design my own cabinet that would provide the required look but also perform from an audio perspective. I then quickly realise that achieving a decent enough finish was probably a task to great for my modest DIY skills, let alone the functional aspects :laughing:

I have made a few modifications to help with the cable side already (it is far from ideal though and has stopped me considering a PS upgrade) and had wondered if supporting cables on or through tensioned rubber bands standing off the back and across the openings would be worth ago…

I have made the contrary: glass shelf directly on the Fraimlite shelf, then finite elemente cerapucks under the pre.

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That big box on top!

Yes, too big to fit elsewhere. So good to have music back. Not having my system during 5 weeks.
Hopefully no service before 4,5 years now ( 555 dr next).

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I have just received a SH Quadraspire bamboo shelf.

Some say that bamboo sounds better than the other wood shelves they make.

Should I install it under the 272 or the 555DR?

(I know the answer is ‘try it and see’ but wonder what theory would suggest.)

So let’s imagine that a bamboo shelf improves SQ by vibrating less in response to movements of the rack by the component on it, the other components on the rack, and from the floor and the air.

That suggests to me that the bamboo might be best used under the 555DR as that is likely to vibrate most.

But then must depend on the specifics of the system in question.

555 dr, but it’s very easy to swap

Not very easy to swop as I have to move components and their shelves and dismantle the rack and rebuild it and redress the cables each time.

Ak ok, it’s not that kind of shelf I imagined, more a shelf like a butcher block but quadraspire.
For me, be it Fraimlite or Lovan rack, I always found that isolation devices work better for the ps than Naim components. But it’s me.

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Hi Jim,

Sorry, I have no idea!
If I did I’d tell you, but I don’t.
:wink:

:woman_shrugging:

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At least I say when I don’t know, rather than just making it up as I go along!
(I could never succeed as a politician could I!)

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Well, I just tried the bamboo shelf under the 272, top shelf.

Then under the 555DR (in pic).

If anything, it made no difference under the 272, compared to the oak shelf, whereas it sounds a bit clearer under the psu.

But I’m 100% certain that any differences are well within my ability to kid myself!

It will stay under the psu in perpetuity.

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OK, Fairy snuff.

I’ve just made another variant that provides greater mechanical stability for use when the box has controls that need to be touched periodically, in this case instead of making the impression with a 15mm ball, I’m using an 8mm ball. The resulting depression is slightly smaller but has steeper sides and is a closer fit to the 6.35mm nitride ball.

This means that the system isn’t quite so resistant to lateral vibration, but it’s a lot more mechanically stable. The difference is SQ is marginal, so, I’ll continue to use the 8mm depression version, but only under the 272, the rest of the boxes will stay on the 15mm system.

I have also finally replaced the last set of my Mk1 black plastic retainer cages with the Mk2 version (the type I sent to @JimDog) these have a greater clearance between the cage and the ceramic ball. They do have a positive effect on the SQ compared to the Mk1s; it’s by no means “night and day”, but overall the lower damping does seem to be beneficial.

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You could sell the brass cups, surrounds and balls.

You’d bring hifi joy to millions.

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@JimDog

To significantly speed up your printing, had you considered using a 0.6 or 0.8mm nozzle?

You have very little detail in the horizontal plane, so if you keep the same layer height you won’t loose any perceived quality (but you can reduce the number of walls, keeping the same physical thickness). The print will then be significantly faster, and it will also be stronger and a little less prone to creep.

(Personally I’d first try a 0.8 for that type of print.)

My experiment with a couple @Xanthe 's isolation shelves has proved to be worthwhile and a success despite the unfortunate compromise of my system residing in big a TV cabinet.

My first set of brass stop ends arrived looking quite different to advertised and were much deeper with an indentation in the centre and to deep for my 7mm nitride balls. They were a good fit for the steel balls I had to make the hardening indentations so I ran with this combination to start with and tried a few different set ups including layering up with the Soundstage I already had. There was definitely some changes but I think fiddling around to much and with slow working inside the confines of the cabinet I ended up rather lost and forgetting where I’d started sound wise. However coming back to it later I did perceive the system it to be more open, or less veiled, and the shelves were doing more than I had initially thought. Not night and day but definitely a step in the right direction.
Subsequently I went on the hunt locally for the shallower brass cups and managed to get some 15mm versions which would suit the nitride balls. I made the hardening indentations and swapped them over with the initial steel balls in the bigger cup and after a lot of messing about finally got all the balls centred (no retainers at this point).
Results; definitely an uplift in overall quality, the depth of sound stage and clarity seem to have benefited most, there’s more air around vocals and instruments and one or two recordings that I always wished were a little less veiled and muddled are exactly that :smile:. In my set up, as would be expected, it’s not a ‘wow’ quantum leap but a grower where you realise after a little while there’s quite a bit more than initially thought. I’m glad I had a go.

Are any thoughts on different sizes of the brass cups? Mine are smaller at 15mm at the moment and seem neat enough, is bigger better?

Thanks again for the knowledge share.

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