Measuring Vibration in Equipment


There are alot of threads on shelf material and tweeks that cut down on vibration. Is there a device that measures this vibration? I think I remember of hearing of such a tool before my audiophile days for testing crates for shipment but I cant remember what it was called. In The Complete guide to Home Audio they suggested using a stethescope. Has anyone tried this?
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Hello RCM and welcome to the site. There are no rules about dealers posting and I would be very interested to know who yoo are. This thread and many others like it were started to get the best sound for our system.

The combined knowledge of this site goes well beyound magazine critics and dealers and each members specialty is based on there individual experience. You will even find that not to many people have respect for magazines or dealers.



This site is filled with very knowledgeable people with world class systems. There are a ton of regular posters and others that just pop up when a specific question needs answering. We are passionate people and sometimes topics like this are considered snake oils and get heated at times. Dont be disillusioned by this its that passion that brings us further into the hobby.

I would like to learn more about those books specifacally where too find them. Even title, author, and isbn number would be very helpfull. You might want to post more info about those measuring devices and programs. They are beyound my reach but many of the members have very dep pockets

All information at every level is appreciated and never worry about getting to technical. You might even find that you learn a few things yourself. You are obviusly very knowledgable in this area and I hope to see your post often sharing your knowledge with us. Welcome aboard!!
Good-day to all of you,

I am impressed and gratified that there are audiophiles now focussed on and studying this topic.

First off, I am a manufacturer who produces products that pertain to vibration control. I do not know if I am permitted to speak within the text of this forum. I will remain anonymous as this information will hopefully not be analyzed as a sale’s pitch. We only wish to further your interests on the topic.

A few of our clients have written information into these forums about our latest products. They telephoned me for additional information and as a favor to them I promised I would review the challenges your feedback proposed to them. My hopes are that audiophiles will discover how multiple types of resonance, including the huge air-borne category, produce problems that extremely limit their equipment’s musical performance.

Out of curiosity, why are you investigating or what process has driven you to this topic? What are you searching for?

We have been dealing with the study of resonance for years within this Specialty Audio Industry. Our opinion is that this category of products are positioned way down there somewhere in the tweak, hocus-pocus, smoke and mirrors and just a plain little old accessory type product design category. It seems our portion of the Industry has never gained the audience needed to improve the reviewers and/or users positioning on the ‘ladder of hope’ that can improve ones ‘emotional’ listening enjoyment.

Our goals and product development will prove beyond any doubt that a rack; loudspeaker stand or a cone combined with new mechanical grounding processes have just as great an impact on your listening enjoyment as your amplifier, speakers, etc. That said, let’s open the doors to some information and have some fun.

A stethoscope will permit you to listen to some resonance patterns and provide you an idea of where and how vibration originates, but will not provide a cure. We highly applaud your insight as we too many years ago began our company using this instrument. One problem with this type of study is you are missing much of the resonance patterns, which are inaudible to the human ear and usually are located at the origin of the demise of the equipment’s performance.

Another method to see small vibrations and their changing movement involves an oscilloscope used in conjunction with an accelerometer. Depending on purchasing a used or new O-scope this equipment could run anywhere from a $500 to a $5,000 investment.

Most of the test equipment that is required to really get involved with this topic is expensive to purchase. The initial financial outlay is usually the problem and what makes the going extremely tuff.

I would like to provide you a company’s web-site that provides information and PC software structured around mechanical engineering that can take you further into the study on a more economical approach. The software programs start at $1,000.00 and can climb into $5,000 range depending how deep you wish to become involved. ALGOR, Inc. also has multiple listings on books dealing with various subjects of vibration, as this is always the most affordable approach to furthering your education.

Here you can find information from an understanding of micro resonance to vibration controlling methods used for large machinery. They too provide various educational programs that you can actively participate.

We highly recommend this company as they have an effective product and support team as well.

ALGOR (Pittsburgh, PA) www.algor.com

We are currently involved with the study of static stress and fluid flows to name a few topics that have taken us away from our usual research programs. I must say this new information has opened even more avenues of study and testing for future product’s development.

We thank all of you who are interested in resonance control and hope this brief bit of information will maintain your interest. At some point I hope our paths do cross.

Very truly yours,
What we have used is small etched piezo devices taped to equipment platforms and feeding a sensitive gain stage (actually a modified phono stage). This gives good results but you have to trial and error a lot to get a reference point from which you can then further study vibration patterns and get meaningful, consistent results. Radio Shack used to sell a small flat piezo mic that can be used. Regards, Richard at www.vantageaudio.com
I use small shallow round dishes. I get mine from a lab glass supplier. Put water in them and shine a flash light on the water. Moving the dish around will show you the major resonance points. Make sure you don't overfill it so the water doesn't bounce out. You can also rent industrial strain gauges specifically designed for vibration measurements but unless you already have a degree in mechanical engineering this is overkill.
call up NOAA in the republic of boulder, give them your exact location via GPS, ask them to run a pinpoint seismologic test and get back your results on the richter scale. could cost a bunch but think how impressed your friends will be.
I wonder if a large well marked (graduated) compass would work? It would be crude but maybe useful?
I used a stethoscope to listen to the walls while I played a test disc of the different frequencies through my system to hear where the most vibration is at what frequencies. Works pretty well to identify trouble spots to treat.
Never used it on racks, etc. though.
I was recently wondering about this myself. I would LOVE to be able to conduct some tests dealing with this subject. Sean
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