Do equipment stands have an impact on electronics?


Mechanical grounding or isolation from vibration has been a hot topic as of late.  Many know from experience that footers, stands and other vibration technologies impact things that vibrate a lot like speakers, subs or even listening rooms (my recent experience with an "Energy room").  The question is does it have merit when it comes to electronics and if so why?  Are there plausible explanations for their effect on electronics or suggested measurement paradigms to document such an effect?
agear
Audiopoint wrote,

"Taking a measurement from the floor and the shelf is a “measurement”. Comparing two comparable scenarios where the tester changes one dependent variable and analyzes the results is “a test”. 88% reduction means nothing if you do not compare it to some second configuration. For all we know one could get the same “measurement” by placing the same equipment on the rack specified without the isolation pads or with a peanut butter sandwich… 88% reduction might be the normal. With the information provided in this “test”, you can’t argue with us. We simply do not know. You need to take TWO measurements and then analyze the difference (delta)."

Funny. 88% reduction at 20 Hz is NOT normal. You guys apparently still don’t understand isolation or what a low pass filter actually is. What is not mentioned in the report - but is obviously the case - is that at frequencies higher than 20 Hz the isolation effectiveness is even higher than 88%, for purposes of discussion circa 97% at 30 Hz and 99.5% at 40 Hz. Those number are fairly typical of ANY reasonably good mass-on-spring isolation device. Furthermore, it’s as obvious as the nose on your face that the 88% reduction was compared to the case without the isolation. You guys just can’t seem to catch a break. ;-)

Are those NASA-spec springs I spy?

http://www.solid-tech.net/products/discs-of-silence-4537455

Have Robert from SS send you some demo stands for your speakers.  You are in for a surprise....
Funny. 88% reduction at 20 Hz is NOT normal. You guys apparently still don’t understand isolation or what a low pass filter actually is. What is not mentioned in the report - but is obviously the case - is that at frequencies higher than 20 Hz the isolation effectiveness is even higher than 88%, for purposes of discussion circa 97% at 30 Hz and 99.5% at 40 Hz. Those number are fairly typical of ANY reasonably good mass-on-spring isolation device. Furthermore, it’s as obvious as the nose on your face that the 88% reduction was compared to the case without the isolation. You guys just can’t seem to catch a break. ;-)
Neither it seems can you.  Where are your measurements Einstein or is this a skill set long forgotten in the fugue state of your "education"?
agear OP
1,223 posts
11-10-2016 12:47am
Geoffkait:Funny. 88% reduction at 20 Hz is NOT normal. You guys apparently still don’t understand isolation or what a low pass filter actually is. What is not mentioned in the report - but is obviously the case - is that at frequencies higher than 20 Hz the isolation effectiveness is even higher than 88%, for purposes of discussion circa 97% at 30 Hz and 99.5% at 40 Hz. Those number are fairly typical of ANY reasonably good mass-on-spring isolation device. Furthermore, it’s as obvious as the nose on your face that the 88% reduction was compared to the case without the isolation. You guys just can’t seem to catch a break. ;-)

To which agear replied,

"Neither it seems can you. Where are your measurements Einstein or is this a skill set long forgotten in the fugue state of your "education"?"

Uh, the 88% reduction is the measurement, troll. As are the other percentages in the report. Besides, the isolation effectiveness for a given iso device of known Fr can be easily calculated (or estimated if you know what you're doing) for any frequency of interest. And the Fr for these spring type devices can be easily determined using the second hand of a watch. Hel-loo! Can I make a suggestion?: if you wish to be an effective troll go back to school. Speaking of which have you given further consideration to marching yourself back to UVa and demanding your money back?

Geoff Kait
Machina Dynamica
give me a stiff enough spring and I’ll isolate the world

agear OP
1,223 posts
11-10-2016 12:44am
Are those NASA-spec springs I spy?

http://www.solid-tech.net/products/discs-of-silence-4537455

Finally! Someone was smart enough to copy my original Nimbus Sub Hertz Isolation platform design; Nimbus used a single vertical air spring with a lateral support spring system - a series of small springs. The difference being the Nimbus used only ONE spring total, whereas other systems are forced (due to the technical difficulty of using one spring) to use multiple springs (to obtain sufficient lateral support) which raises Fr of the iso system. The best Fr achievable with multiple vertical springs is about 3 Hz. Which it’s bad, but it’s not anywhere near as good as 0.5 Hz. The reason 0.5 Hz is important is because the peak Earth crust motion is between 0 Hz and 2 Hz. That’s why the Nimbus Unipivot at 0.5 Hz Fr is still the best, even 20 years later. Hel-loo! Addendum: for speakers the Fr of the isolating device is not critical since the lowest frequency that needs to be isolated is what, 25 or 30 Hz?