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Measurement Means and Methods

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I'm mostly an electronics guy but now and then I venture into speaker design, like for my SpeakerCamp project. In looking for test methods for speakers I came across a very interesting article by This email address is being protected from spambots. You need JavaScript enabled to view it. , who designed an accelero-meter based test set to measure mechanican vibrations from speakers and enclosures. I purchased the PCB from George and build up the unit, and it has been a very worthwhile addition to my lab. In fact, I had trouble getting it back from friends who loaned it 'just for s few days'!

The article has been published in AudioXpress and they have agreed to place the article online for those who missed it. Also, This email address is being protected from spambots. You need JavaScript enabled to view it. let me know that he still has PCBs and front panels available to help you get going quickly and cleanly. Recommended for anyone who really wants to know about enclosure vibrations and the effects of bracing, material selection and stiffness etc.

 

Dr. Hirata et al Engineering Report for the AES from April 1981, on a distortion measurement method that gives insight into the TYPE of non-linearity rather than a single distortion number: Non-linear Distortion Measurement Using Composite Pulse Waveform.

A different, but related type of transient testing by Southworth, from 1966.

Contribution by John Curl related to the LT1166 bias chip. The measurements are here and here.

Notch filter Auto-tunes for audio applications - John R Ambrose (EDN July 2010)

HP 3577A application note for using the 3577 to do loop gain measurements of a feedback loop: HP PRODUCT NOTE 3577A-2

"Possible methods for the measurement of transient intermodulation distortion", Matti Otala and Eero Leinonen, Technical Research Center of Finland, 1976.

 

Want to build one of my designs?

I am flattered but would also like us to agree on a few rules.

My designs are the best I can make them, including reliability and safety. A lot of effort, time and money goes into them, and I enjoy doing it.

Nevertheless, I have obviously no control over how, where or when somebody would use a design of me. Therefore, I cannot guarantee that it will do as advertised in all cases and circumstances. I also have to decline any and all responsibility for any damages, direct or consequential, resulting from the use of my designs. Sorry about that, but that's how my lawyer wants it...

If you want to build one for your own use, go ahead. It would be nice if you would let me know how it all works out.

If you like to use one of my designs for a commercial product, we can discuss the terms of such use. If you plan to make money out of them, I would like to have some compensation for my work and effort as well. Or, if you are in need of a design consultant for a project, let me know. I’m sure we can work something out to mutual benefit.