Behringer MICROHD HD400 Stereo Hum Destroyer

If used for the correct applications, its truely better than expected for a bit over a $20. Worth twice that!

My model is black instead of white. I bought this because my home recording PC had some noise. This is not a true "hum" but more of a scratching/electronic noise that happened whenever there was activity on the PC. My line in on the PC is connected to a mixer. I found that this noise happened with any mixer that was plugged in, regardless of if I had them plugged into the same power strip. I even tried a power conditioner, but the noise was still there. I received the HD400 yesterday, plugged it in, and voila - no more noise! Exactly what I was looking for!

I found that I could the same noise reduction another way but I liked the product.

The HD400 provides two decent-quality audio isolation transformers at a price that no other manufacturer can touch. Each transformer provides balanced-to-unbalanced conversion (or vice versa) and has a very flat frequency response in the audio band (I've measured them under load). Each transformer is also shielded. They effectively eliminate hum and noise caused by ground loops. If this device doesn't solve your problem, then your problem was not a ground loop. If your problem is a ground loop, this device WILL solve it (assuming you place it appropriately); whether it is hum from AC mains, or high-frequency hash caused by ground loops when using a computer. If your system is poorly designed or implemented, you may need more than one HD400. Unfortunately, diagnosing and eliminating ground loops can be non-trivial and beyond the scope of many musicians' technical skills. You can, of course, find higher quality transformers (Jensen, etc.), but you are going to pay MUCH more for them. I have not seen a better value than the HD400, anywhere.

This Made my pedals amp and guitar Hum worse

I've had a terrible hum interference from dimmable side lights needed for a music performance. The hum was loud and very annoying without the volume turned up for you to hear sound from the speakers. The Behringer HD400 did nothing to help with the hum. I removed the HD 400 and hooked up a Furman M-8x Power Conditioner instead, and it solved my problem. The performance went very well even with the audio at a high volume I didn�ۡ���t hear the hum, and better news is the audience didn�ۡ���t hear it either.