Stands for the Black-Faced Naims

Aha! The wobbly Quadraspire reference is indeed my stand of choice.

So, what about rubber mounting the boards in old Naim kit? I have done this to good effect in valve amps in the past to avoid microphony. I used short lengths of silastic catheter tubing cut to form thick washers, which were then threaded onto the board stand-offs.

malcolm

The problem with implementing decoupling systems such as that used by Naim in some equipment is in my limited experience that of defining the bandwidth correctly.

Compliant springs / large masses have a fundamental resonance that's sub-sonic - you don't want to introduce decoupling resonances within the audio band.

I suspect that the low mass of a PCB, coupled with the relatively stiff compliance afforded by such tubing would do just that.

The circuits as a whole may also benefit from being 'rigidly' held at higher frequencies.

You'll know when you've got it wrong - it all falls apart musically - fun stuff to try though.

Look at the slow sway of a large stack of Mana, the wobbliness of Quadraspire etc. may give you some clues!

Andy.

Thanks Andy

Good to see you posting here again

malcolm

must be the new look forum

[This message was edited by Rockingdoc on TUESDAY 07 January 2003 at 14:31.]

It seems to me that black-face sheep are pretty common everywhere
malcolm

I'd assume the boys and Naim would have optimised the Fraim for the new boxes, not too sure about the old stuff though...

To me any other compliance (ahhh sorbothane - its a music killer) defeats the whole purpose of the stand. Why buy and rack, and then add something else to interface

Wisdom would suggest that the boys at Naim have rigged (optimised) to the new gear (fraim/new boxes).

naheed...

My sorbothane blocks are to protect against vibrations from the power-supplies infecting the sources on the same rack. They hum, so must be vibrating. I don't believe that power supplies can be made to "sound better" by fancy stands.

malcolm

(ahhh sorbothane - its a music killer)
well said naheed, I have never had a postive result under our kit with this material.
It may work for others.

No the new kit was not optimised for the fraim, the stand works just great with any kit!

The power supplies still have to stacked because the Naim system is in a very small room.
Everything else has its own support or shelf.
I will (just about) accept that the Scap might benefit from separate support, but won't believe it for things like the Lingo.

Re: Sorbothane

This material has a very high damping factor, the idea being that the energy passed into it is dissipated (as heat).

The problem with applying damping to any decoupling device (i.e. spring / mass assembly) is that it reduces decoupling at higher frequencies, yet has little or no effect on resonant frequency. The LP12 suspension is an interesting example - the principle of operation is that the arm / platter / subchassis is decoupled from the outside world (a large mass supported by springs). The platter / arm / subchassis ass'y though is rigidly coupled together such that it all moves together and is exposed to the same forces such that there differential movements that would give rise to errors in retrieval.

My guess is similar principles could apply to electronics, even though they are not tying to 'measure' something mechanically.

Andy.

Agreed, and although harder to predict the results compliant supports for electronics could have something to offer, but are dismissed out of hand by the rigid-supporters., The difference in my case is that I am using the damping to protect or isolate the rigid support from vibration produced by the power supply.

Another difference is that the electronics themselves have a number of vibrating devices within them (transformers, mechanisms) that may benefit from mechanical grounding, otherwise the energy may have a greater effect on the electronics themselves.

I suspect this is another area where compromises have to be made.

I spent an interesting evening a while ago playing with my partners stethoscope (on the HiFi!) the amount of energy present on the cases of my electronics is fascinating to hear - buzz from transformers and clear renditions of whatever was playing at the time...

Andy.

Did you use the diaphragm or the bell side of the 'scope? Each favours a different frequency band.

Blimey - I learn something new every day!

I only used the diaphragm, being an amateur

I'll have a play again if she'll let me...

Andy.