Hi-Fi and Pro Audio

"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)

"I think you build an excellent product that the audiophile industry ought to know about" K.F

"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

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. 

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.

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).

Questions?  Ask Us:

Relevant Products:

CleanSweep AC EMI filters outperform regular EMI filters in real-life applicatons

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).

 ©2017-2021 OnFILTER, Inc. CleanSweep is a registered trademark of OnFILTER

U.S. Patents 10,263,591; 9,076,806B1 All specifications are subject to change without notice.

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