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Component isolation

Let’s say you’re going to add isolation feet to a component with no moving parts, such as a preamp, phono stage, DAC, amp, tuner, etc. 

Which one is most critical to the extent would get your attention first? 
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michaelgreenaudio's avatar
michaelgreenaudio
1,019 posts
 

Hi millercarbon, thanks!

When I got into the HEA part of this industry I did so with some good advice from the guys who I worked with in the studios and on the road. I was known among some for coming in, doing my thing and quietly staying off to the side while the sessions went on not getting involved in the debates, credits, money or theory building. The advice was "never change that rule of mine". It's served my goals well and has given me valued friendships and a clear understanding of what it takes to become a long term standard.

We have a wonderful industry and hobby, all the way from instruments to the ear, and I have tried to be in every position of "Doing" I could have so I can be a forever student of this passion. The only way I knew to do this was jump in, do, and learn for myself without being influenced by talk minus the doing. There's a completeness about doing something for ourselves and if we do so in time the truth makes it's way to us. It's a process that may happen in a moment or one that may take a lifetime but truth itself is never false, and the learning of it is truly a matter of doing.

So for me, when people say that's not the case, can't be true, he's full of it, wow that made an amazing difference or whatever suits their proclamation, I know if they have really done for themselves they know. And as important, if they haven't done for themselves they may never know what has been waiting for them to yet be discovered.

Audio is not a world of assumptions, neither is audio recording and playback. Audio is a science that we will either do or not do.

Again thanks, it means a lot to me. Not that I was right or wrong, but that you saw I was a student of sound just like you with the same goal and passion! all my best

mg

michaelgreenaudio's avatar
michaelgreenaudio
1,019 posts
 

Hi Terry9

you said

"Michael, you say that," ... when you dampen vibrations you’re also dampening part of the audio signal." In my system, parasitic resonances (all resonances are a form of vibration) such as those excited in the tonearm, are not part of the audio signal. So I damp them out. Don't think you can have thought this through."

As I've said above, I'm a do it guy. If your ears have given you a different result of course you have to be true to your ears.

mg

michaelgreenaudio's avatar
michaelgreenaudio
1,019 posts
 

bdp24

"Components should simply reproduce the sound of instruments (and voices) contained in recordings, having or adding no sound of their own."

Wouldn’t that be nice! Or our ears, or our rooms, or our brains, or our locations, or our planet on it’s revolving. Or our orbit...and on and on it goes.

the variables buddy, don't leave out the variables

mg

geoffkait's avatar
geoffkait
23,365 posts
 
tt1man4 posts03-17-2019 8:47pmHello all,
As a manufacturer of pneumatic isolation devices (feet), am I permitted topost our website which contains pertinent isolation/vibration information, and an informative White Paper? If so, can our technical director also join in on this discussion? Thanks in advance for your feedback and consideration.

>>>>>Go for it! Don’t be shy.
geoffkait's avatar
geoffkait
23,365 posts
 

kingbarbuda14 posts03-17-2019 9:40pm**Leaving to ask what would be the incremental benefit of *any* expensive vibration resolution solutions.

>>>>>Generally, the two determining factors for isolation device performance are resonant frequency Fr of the iso device and number of directions of isolation (degrees of freedom). Thus, the spring rate of the spring should be as low as possible for a given weight of the component. Very Stiff Springs 🏋🏻‍♂️ must obviously be used under very heavy amps, speakers and turntables, otherwise the component will topple over due to insufficient lateral support.

As I already pointed out a Fr of 5 Hz will result in transmission of 90% of vibrations with frequency of 10 Hz, whereas if the Fr can be reduced to 2 Hz the percentage of transmission for 10 Hz vibration can be reduced to 50%. The low pass filter characteristics of mass on spring isolators provide very low transmissibility for frequencies greater than 20 Hz. But obviously there’s an incentive for trying to achieve very low Fr. My Nimbus Sub Hertz Platform was the first audiophile iso stand to provide six degree of freedom isolation. By contrast, most audiophile iso stands provide one or two directions of isolation, the vertical direction 🔝 and horizontal plane 🔛.

There are six directions of motion for any object, including three rotational directions around the x,y, z axes, respectively. Forces in rotational directions are usually caused by Earth crust motion that is analogous to shaking out a carpet or a wave 🌊 passing under a boat 🚣‍♀️.Thus, the ideal vibration isolator addresses all 6 directions. But the more directions addressed by an isolator the greater the complexity and cost, generally speaking. A combination of mass-on-spring isolators and roller bearing assemblies can provide isolation in most of the six directions, for example.

There are additional factors involved in effective vibration isolation, such as method of mounting the component on the top plate of the iso stand, method of mounting the iso stand on the floor or rack, and method of reducing “residual vibration” on the top plate of the iso stand. The geometry of the spring or airspring is yet another variable. A bicycle 🚲inner tube, for example, has a very non-ideal geometry. And the airspring used in my Nimbus Sub Hertz Platform had ideal geometry, whereas the air bladders used in some iso devices are not at all ideal geometry-wise.
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