Faint buzz in speakers


There is a very faint buzz coming from speakers with amp on, but with no music stream playing. Can only be heard with ear right up to drivers. No buzz with amp off or muted. Decent amp & cabling. Is this faint buzz likely still there under music when it’s playing? Numerous noise reduction devices deployed including dedicated circuit, robust grounding, balanced power transformer, various filters. Thoughts?

jmfinney

I had the same insidious problem. It was caused by the ground plug. Even though it is NOT recommended to use, I simply installed a ground plug adapter and eliminated the ground prong. It worked. Buzz was finally gone!

It was the ground plug on my pre-amp that did it.

Be aware you are eliminating an important safety feature when you do this.

I had a buzz or ground hum years ago, and after trouble shooting with the dealer ended up installing some gadget between ac cord and wall outlet that fixed it.  It was called 'Magic' something.

A search found this:

https://ifi-audio.com/products/gnd-defender/

More than a 'cheater' but still retains safety of grounding.

Two things to try.  Turn off every other breaker in your home. if that makes the problem go away you may have some device introducing DC. This happens when a device/appliance sucks more on one side of the waveform than another.  Often in very cheap DC supplies.

If it's still buzzing, disconnect all inputs. 

@jmfinney I had exactly the same issue! After replacing US brand pre+amp with Accuphase C2420+AD2820 + P4500/A48, such noise disappeared! 

@OP Some amplifiers have small amounts of residual noise thought it should usually manifest itself as white noise, but there can be other noise as well. It is also possible that one or more of your noise reduction devices are causing the noise - including your balanced power unit. Take them all out of circuit and introduce them one by one. If the noise is still there after that, its most likely the amp itself. However, if you can't hear it from the listening position I wouldn't sweat about it.