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


Hello,

I was looking for a very good/robust power conditioner which will clean up reliably very noisy/dirty power supply that I have in my aprtment. While looking for one I went through catlogs of AudioQuest, Shunyata Research, Synergestic Research etc. but no one published charts showing attenuation performance over frequency range like you get for EMI filters from Schurter or Schaffner etc. which are in the industry for EMI/EMC compliance.

Since audio is very subjective, but contrary to audio reproduction Power and EMI/RFI reduction is completely objective and can be clearly demonstrated via attenuation charts.

Hence I am asking if anyone has measured the actual performance of these audiophile power conditioners. I am not denying someone saying they hear improvement after using XYZ product, but since I am talking about power conditioning or EMI reduction it's as objective as it can be.

I am not at all surprised to see all the manufacturers not publishing the performance data, else it would be used in other industries and research fields where it's far more critical and have far more stringent requirements on the performance of conditioner/EMI filters. But I am shocked to see even products ranging above 5-10K are following the same practice of not publishing the results.

Please note I am not a measurement fanatic, but I know where I can chase the measurements and where I can rely on my hearing to gauge the difference.

Regards,

Audio_phool

128x128audio_phool

I am adding a separate column for frequency range specified/mentioned.

Sr. No. Manufacturer Model EMI/Noise Reduction Frequency Range Specified Mode Specified Load Specified Cost
1 Shunyata Everest More than 50dB, 68db @ 1 Mhz 100 KHz to 30 Mhz No No USD 9,900
2 Shunyata Gemini More than 40dB, 28dB @ 1 Mhz 100 KHz to 30 Mhz No No USD 1,998
3 Shunyata Venom PS10 More than 24dB, 28dB @ 1 Mhz 100 KHz to 30 Mhz No No USD 900
4 Audioquest Niagra 5000 More than 30db for CM & more than 28 dB for DM 3 Khz to 1 Ghz for DM & 60 Hz to 100Mhz for CM Yes, CM & DM 10 to 50 ohms USD 5,900
5 Audioquest Niagra 7000 More than 30db for CM & more than 28 dB for DM 3 Khz to 1 Ghz for DM & 60 Hz to 100Mhz for CM Yes, CM & DM 10 to 50 ohms USD 11,000
6 Audioquest PowerQuest 303 More than 22 dB for DM 3 Khz to 1 Ghz for DM Yes, DM 10 to 50 ohms USD 460
7 Synergistic Research Galileo PowerCell SX No No No No USD 27,995
8 Synergistic Research PowerCell SX No No No No USD 9,000
9 Synergistic Research PowerCell ONE  No No No No USD 1,095
10 PS Audio Power Plant 20 More than 80 dB 100 KHz to 2 MHz No No USD 8,000
11 PS Audio Power Plant 15 More than 80 dB 100 KHz to 2 MHz No No USD 6,399
12 PS Audio Stellar Power Plant 3 No No No No USD 2,399
13 IsoTek EVO3 Super Titan 85dB No No No USD 12,495
14 IsoTek V5 Titan 85dB No No 50 ohms USD 4,995
15 IsoTek V5 Elektra 55dB No No No USD 1,695
16 Puritan Audio PSM 156 No No No No USD 2,400
17 Puritan Audio PSM 136 No No No No USD 2,100
18 OnFilter AF Series Graph Provided for CM & DM. Max 98dB in DM, Max 62db in CM 10 KHz to 50 MHz Yes, CM & DM  1:100 USD 650
19 Schaffner FN 2090 20A Graph Provided for CM & DM. Max 100dB in DM, Max 82db in CM 10 KHz to 100 MHz Yes, CM & DM  50:50 USD 70

 

This will give a complete set of info which is as available on the product page/in manuals.

So as the anlysis of these figures availble, I can conclude that for most of the audiophile grade power conditioner manufacturer, the available specs are usless as they do not tell the whole story except for the Audioquest which tells specs only at Lab specs & not the real world scenarios.

Synergestic reseach is not publishing any spec at all even for their 28K unit which is criminal IMO. Considering the price of these units not disclosing the full specs can be considered very dubious. Whie Audioquest has discolsed their lab setting specs, they are sub-par and even $70 Schaffner filter has better noise reduction performance (which also specifies only lab condition vaues) which is the main function of all these units.

The only one to stand out of all these is EMI Filter by OnFilter, as they provide data for real world values instead of just Lab setting vaues & their performnce is very impressive indeed and that too at a lower price than all other audiophile counterparts.

Audio_phool

audio_phool

... I can conclude that for most of the audiophile grade power conditioner manufacturer, the available specs are usless ...

That's why it pays to test components in your own system.

Synergestic reseach is not publishing any spec at all even for their 28K unit which is criminal IMO.

Criminal? Really? Good luck to you as you try to warp the law to suit your opinions.

A note on input/output impedance: most measurements in RF domain are made in a 50 Ohms termination.  Conducted (i.e. on wires) EMC test per regulations is also conducted with 50 Ohms termination.  Appliance filters (this is the UL and IEC classification of the filters built into equipment to make it comply with EMC regulations) such as made by Schaffner and so many others are therefore optimized for 50 Ohms termination. One may say "tuned" for such termination for maximum attenuation. The problem is, I haven't met a power line of 50 Ohms yet.  More realistic matching impedance accepted in the industry is more like 0.1/100 or 1/100 Ohms, where the lower impedance is the source (i.e. your outlet) and the higher one - your load.
Some of the better appliance filter manufacturers like Schaffner (give it to the Swiss - they have specifications) and Schurter used to list in their datasheets performance at both 50 Ohms and 0.1/100 Ohms.  However, lately Schaffner has "sanitized" quite unfavorable data (I do have saved their datasheet from before the "cleansing") and for the most of their products they list only 50/50 Ohms data.  The only one I found which still has complete data is their FN343.   
Schurter still provides "honest" data for their filters - see this  as an example (you would need to figure your way on this page).

Scroll down and find the attenuation curves.  What you see is that 0.1/100 and 100/0.1 curves show "negative" attenuation at lower frequencies, meaning actual EMI amplification.  In short, in an EMC test lab this filter will help to comply with CE/FCC requirements; when plugged into real outlet - it will amplify noise. 

I wrote an article for inCompliance Magazine on the discrepancies between EMC regulations and the real world which, in part, addresses it.  

Look at the section called "50 Ohms Question"  You can find this and other articles in our online Technical Library

A corollary issue is the frequency range.  When you look at the above-mentioned Schaffner or Schurted data, note that the real-life attenuation curves end at 1MHz. There is a reason for that.  Parasitic capacitance and inductance of power cables essentially kills higher frequencies.  Now, what are the sources of the signals in a typical residential environment (for audio purposes)?  It is, in no particular order of significance, switched mode power supplies encompassing LED lighting, solar and other inverters, plug-in supplies for just about everything, TVs, and the list drums on.  Another source would be variable frequency drives (refrigerators, pumps, A/C, washers, dryers, etc.).  All of them operate at lower frequencies - SMPS, for example, work somewhere between 40kHz and 150kHz.  1MHz attenuation data that I see are not that relevant for real-life applications.

@cleeds not everyone has the option/luxury of trying all at home. So listening is not always the viable option. Why you want to defend these manufacturers for not providing specs is beyond me. Besides if you don't find anything wrong with zero specs for a power conditioner costing $28K then may God help you.

@vk_onfilter thank you for providing the real information and not something which these audiophile companies keep on blabbering.

Regards,

Audio_phool

 

audio_phool... not everyone has the option/luxury of trying all at home. So listening is not always the viable option ..

Many local dealers allow in home auditions. Many online dealers allow returns.

... if you don’t find anything wrong with zero specs for a power conditioner costing $28K then may God help you.

It’s not likely that an audiophile will spend $28K on anything without an audition first. You’re just being silly.