Any one measured the EMI/RFI attenuation performance of audiophile power conditioners?

@vk_onfilter I saw the productline of your company which looks impressive & you seem to serve diverse industries including chip manufacturing, R&D centers etc. and you have provided the performance chart for your products. Besides you seem to have more than 40 years of experience in the field of EMI/RFI reduction/compliance. Is application of EMI/RFI filtering to audio any special than other industries you serve which allows one to not to specify the performance data? Can such practice will be acceptable if the same product was to used in other industries than in Audio?

Audio_phool

@deep_333 Your example is a very poor one. Since you quoted that only one manufacturer existed, then obviously you had no other choice to find a workaround. So it doen’t apply to current situation as you have a neumerous manufacturers providing the product. Besides power for Audio isn’t anything really special either so don’t try to make it sound something very special. It’s attitude of audiophiles of accepting subjectivity in every thing under the sun has lead to manufacturers take advantage.

Besides even though I have technical lnowledge and come from research background I don’t think engineering degree is needed to understand the need of measurements for power conditioning products which cost and arm and leg. Just common sense is needed.

@tonywinga I doubt those certifications will cost so much that power conditioners costing tens of grands cannot cover it. Besides Im not going to get into cables, thats another debatable topic.

Audio_phool

Just pack your bags, start a thread at ASR and tell them what a measurement wiz/data driven technical genius you are. The A’gon guys and every manufacturer designing power conditioners for hifi applications (Michael Borresen, Garth Powell, etc) are all soaked in snake oil indeed. They can’t keep up with your unmatched genius.

Goodbye now

@deep_333 do youself a favor and get out of audio rabbit hole to see that even $10-$20 commodity grade EMI filters have the specs/data published. So if me insisting on specs/measurements is going to get you worked up so much; it's better for you to say goodbye. Else you have a job to keep these manufacturers alive in the audio industry, as they won't survive outside Audiophilia with this way.

Audio_phool

What will you do with the attenuation performance data of a power conditioner, if you ever get it?  Will you have the power coming into your home analyzed to determine the best fit power conditioner for your needs?  Is getting this performance information an academic exercise?  Or more importantly, are you concerned that a manufacture has significant product variation such that copies of the same power conditioner will affect the sound differently in your system?  Has anyone ever done such testing?  I know camera lenses can have significant variation among copies such that some people will order multiple copies of the same lens and keep the one they like best.  

Otherwise, published specs do not mean much to us (or is it we) end users except for application specific specs like amplifier power at 1, 2, 4, and 8 ohms or the input/output impedance of a preamp or amp.  A speaker manufacturer typically provides efficiency, frequency response measurement data and impedance curves but they do not provide information on the individual drivers used or the tolerances of the component values in their crossovers.  

Also interesting might be how much filtering amplifier and DAC manufacturers design into their products.  That is not typically listed in their specifications although some will tout their copper plated metal chassis construction or such; but still do not specify the difference it makes in noise rejection.  

To answer @Audio phool's question (sorry for a long reply - didn't have time to condense it):

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QUESTION: "@vk_onfilter I saw the productline of your company which looks impressive & you seem to serve diverse industries including chip manufacturing, R&D centers etc. and you have provided the performance chart for your products. Besides you seem to have more than 40 years of experience in the field of EMI/RFI reduction/compliance. Is application of EMI/RFI filtering to audio any special than other industries you serve which allows one to not to specify the performance data? Can such practice will be acceptable if the same product was to used in other industries than in Audio?

Audio_phool"

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The basic foundation of any technical product is a specification.  Engineering Bible starts with "In the beginning there was a specification" :)  In a number of ways a specification tells the designers of the products what a product should accomplish, in very specific terms (not "it should reduce noise a whole lot" but by how may dB at which frequency, and how it should be measured).  It tells the manufacturing group of the company that every single manufactured unit needs to meet or exceed very specific parameters (again, not just "sound good").  It is also a commitment that a supplier of a product gives to a customer - after all, the customer gives similar commitment to the supplier in a form of money.   Whenever you see a product that claims a whole lot but lacks that very specific commitment, it tells you quite a bit.  In the most benign case this would mean that a manufacturer has no idea what does this word "specification" actually mean - not a good notion for any product, especially a technical ones.  Anything else points to either knowing what that specification actually is and not being willing to present it to the customers; or thinking of a customer as an idiot who would buy anything "shiny" that is accompanied by flowery language and inflated price.  
In your own business, whatever it is, you likely buy and/or sell products and/or services.  Would you pay money in your business for something that has no "specification" of the sufficient type?  Would you feel right selling something where your customers have no idea what they are buying?

All our filters (of which AC EMI filters is just only one segment) have specification - sufficient to those in the industry who are in a need of noise reduction.  If we didn't have specifications and didn't stand behind it, truly, very few companies would even consider working with us.  From our perspective there isn't a difference between an EMI filter for a R&D center in a major university and the one for home audio - the only difference is so-call leakage current requirements to comply with the safety regulations - UL1283, UL/IEC 60939 (all our AC EMI filters are safety-certified by an independent accredited laboratory).  We have two basic kinds - industrial type, and hospital/medical/residential grade - grouped by the leakage current limits.

The sole purpose of a filter is to block to the best of its abilities incoming electrical noise and not affect in any adverse way the power itself.  Anything else is not a filter's job.  I believe it would be a mistake and an unreasonable expectation that somehow a filter (or a power conditioner) will improve sound quality, short of reducing incoming electrical noise.  Whatever quality problems you may be experiencing, don't start by adding a filter, unless all you need to reduce is noise.  Now, a poorly-designed filter/conditioner can add plenty of problems by itself, including intermodulation distortion, clipping, and so on - this is where a professional-grade product works, and the "shiny" ones may or may not.  

I do hear time to time from our customers in audio market that our filter either improved sound quality, or it didn't.  I would LOVE to know which specific parameters were affected - if only we knew it, the sky is the limit for the future improvements.  Studying for my MSEE specializing in audio I went through a good number of courses such as psychoacoustics, medical aspects of hearing, and alike.  I remember how at the conclusion of our course on Acoustics (a very demanding course because it is half-analytical and half-empirical) our professor said to the class "Now you know all that a man knows about sound, but only God knows what a man wants to hear" - that's sums it up.  I fully respect a huge subjectivity aspect of listening; I am also cognizant that if one buys an expensive "shiny" piece of equipment, one's brain works overtime to convince itself that it now sounds better for sure.

So, to conclude way-too-long of an essay, no, there is no difference for us in the filter design nor in requirements for the detailed specification for audio and for industrial or R&D market, short of safety regulations.