Hi-Fi and Pro Audio
Photo ©2025 Harris Fogel
Thanks to everyone who visited our booth at T.H.E. Costa Mesa show in June! It was great to meet people genuinely dedicated to a good quality audio.
We exhibited two products from our line - CleanSweep AC EMI filter AFN515FM and filtered PDU ARN5156FD. Here is link to a short video (~5 minutes) demonstrating performance of CleanSweep AC EMI filters.
Here is our CleanSweep filter AFN515FM with the screen of the oscilloscope in our booth. The top (yellow trace) is the EMI noise in the outlet of the exhibit hall, the bottom (blue) trace - after our filter.
Our patented CleanSweep filters, as well as our filtered PDU offer comprehensive EMI suppression in differential mode, common mode, and, uniquely, in ground (this covers all possible ways how EMI from power and ground can get to your equipment). To see ground filtering in action watch this short video (~5 minutes) - ground filtering inside the CleanSweep filters and the PDU is the same as of our stand-alone ground EMI filters.
The units (CleanSweep AC EMI filters) wiped out any background electrical hash- and produced the quietest background I’ve ever heard in my system , remarkable for vacuum tubes amplifiers...Frankly, I think this is benchmark product.
Thank you for your time and patience conversing with me on the phone
R.H., USA
It took me just 5 mins of playback to realize that this is an amazing product. It has significantly improved the SQ of my system. All the regular superlatives apply in my case to the improvement like bass has become tighter, details have increased, micro-transients have improved, sense of black background is even more, music sounds more organic, notes decay for longer etc. etc. The list goes on and on. I am enjoying music even more now.
"AudioPhool"
"We installed the filters, did some initial testing, and then did some more extended config and testing. So far we have been rock solid on amp performance, and according to the audio install guys, it seems like we are both getting better raw performance as well as have had the system running without issues longer than it ever ran previously. "
Church Sound Installation, Chicago
"I tried a number of power conditioners, filters and EMI/RFI reducing products marketed to audiophiles. None of them had much effect reducing EMI/RFI. The only devices that performed as promised and significantly reduced EMI were CleanSweep filters made by OnFilter."
"I think you build an excellent product that the audiophile industry ought to know about" K.F
...just installed the filter and i went from 1000 mv to 150 mv of noise using a emi broadband meter, noticed tighter bass response and extended high frequencies. There was also an increase in dynamic range. Much appreciated! S.A.
With the substantial effort and budget put into achieving superb sound quality, it would be a pity if EMI from power lines and ground ruin it all by adding its "creative content" to the sound.
OnFILTER' CleanSweep® AC EMI filters were designed to deal with industrial noise that exceeds anything that one could encounter at home or in a studio, often by several orders of magnitude. CleanSweep® filters are capable of attenuating high-frequency artifacts on power lines and ground from tens of volts easily found at the factories down to just a few millivolts, enabling operation of super-sensitive semiconductor equipment and quantum computers.
EMI found in home or in a studio environment is easy for CleanSweep® filters. The filters offer noise suppression in both differential (between Live and Neutral) and common (Live/Neutral to Ground) modes and, uniquely, in ground, completely isolating your equipment from EMI on the mains.
Importantly, CleanSweep® filters are not transformer-based. Transformers in power line present high output impedance for the load, i.e. your amplifier. This leads to variations of supply voltage with current peaks and, as a result, to intermodulation distortions, reduction of dynamic range, and other artifacts. Transformless design allows for full dynamic range without added distortion.
AFN515FM
What if your audio setup has several components? Our filtered PDU will provide clean power and ground to them all. Built on CleanSweep AC EMI filters, AR series power distribution unit (PDU) has identical performance to AF series filters blocking EMI on both power and ground.
In addition to dealing with EMI, AR series PDU has dual stage of advance power transient surge protection with suppression performance unachievable just by standard MOV-based surge protectors.
Both products are transformless, allowing for low output impedance that does not restrict dynamic range and does not introduce intermodulated distortion.
A common myth about transformers is that they excel in suppressing common mode EMI. Not true - read independent review in EDN Magazine (covers our MSN15 EMI Adapter and CleanSweep® AC EMI filter).
Read this Application Note for more details and guidance on filter's installation.
Relevant Products:
OnFILTER Products for Audio Applications
Audio Applications
Application Note
Questions? Ask Us
"Just a quick note to say thank you for the noise filter. The filter has proven to be completely effective in eliminating any of the issues I was experiencing. So effective in fact that I cannot even hear the amplifiers’ toroidals in operation at idle or under any listening levels with my ear on the amps’ case. The amps’ noise floor is now utterly silent, and it seems to be running slightly cooler as well. Thanks again for the excellent filter" (R.B., Canada)
Watch the Test of CleanSweep AC EMI Filters
Watch the Test of Ground EMI Filters
Note on Installation
CleanSweep filters uniquely provide filtering in ground, therefore it is critical that you power all your equipment via the filter to avoid EMI on ground sneaking in via some unfiltered component. If you need more than one outlet, you can use any quality power strip connected to the filter's output - no additional filtering in it please, just assure that it has adequate wire gage of at least AWG12 - see App. Note
Performance of CleanSweep AC EMI filter vs. transformer (read review)
CleanSweep® AC EMI filters are not the same as the conventional filters you can find elsewhere. Regular filters are designed to perform only in an artificial laboratory conditions with 50 Ohms power termination. When plugged into actual power mains, they may amplify noise - see above. CleanSweep® EMI filters are designed for real-life applications (they perform well in the lab too).
Application Notes
Technical Articles
