Ferrite Ring Core Ferrite Beads Clip RFI EMI Noise Suppressor Anti-Interference Cable Clip for 3.5mm/ 5mm/ 7mm/ 9mm/ 13mm Diameter Cable, Black (20)

Does what it says. Works great

They seem to work good in cutting down noise, or QRM, as we call it in Ham Radio. Sometimes requires using more than one on the same coax, etc, but glad I got them!

Multiple sizes. Auto radio noise suppressor.

Just put these on my old computer speakers because I was hearing the radio through the speakers and they worked immediately, the noise is gone.

I appreciate that there is a variety of sizes, and they are easy to put on. In my particular situation, it did not address the issue - a hum in a tube amp probably caused by a ground loop - but for very little effort, it was worth a try and certainly didn't make anything worse.

Always good to pop on a few if you have audio specific needs and want to take interference away. Wasn't a drastic improvement but helped some

I have 3 studio monitors (L,R,mono reference) and used 6 of these, 1 on each balanced XLR cable and 1 on each power cable. Prior to installing these, my cell phone would cause hissing/pop/general interference within 4-5ft of each speaker. Now, I can stick the phone right next to the tweeters and cones, and zero interference. This was my first solution to the problem as it is very inexpensive, and I'm so happy it worked.If anyone else has these issues, I highly recommend you give this a try as its very cheap, and worked 100% for my issues.

I'm giving these 4 stars because I know they work, and they seem like a quality product, but they didn't solve my issue. I was hearing a buzzing noise from my speakers (not a ground loop hum) when I scrolled my screen or moved my mouse. I tried many different things, including these ferrite rings, using one, and then a few, and even looping the USB cable through a larger one with one and two loops. Nothing made any difference. Balanced audio cable from my DAC to my amp solved the issue.