Fosi ZA3 Amp has weird backgroun noise with XLR Connection

[decomo]

Hello.

I recenty got Fosi ZA3 stereo amplifier and it works fine with RCA unbalanced connection but when I connect it with XLR balanced connection, it has weird background noise. It gets louder when volume gets higher. I made quick recording of it. Can anyone tell me what may cause this noise and is there any remedy for it or need to ask for replacement under warranty?

Dropbox

www.dropbox.com

Thank you...

 

[TheRealLGC]

XLR cables should be shielded. But to eliminate the possibility of cross talk with other cables, can you isolate the XLR cables and the ZA3 from the rest of your setup & see if that eliminates the background noise ?

 

[xNORgate]

I recenty got Fosi ZA3...t with XLR balanced connection, it has weird background noise.

I listened to your recorded noise through one of my ZA3, which I use on my desktop. Then, I checked my other ZA3 for 'noise' and heard nothing of the sorts from either.

Have you checked the pin-out on the XLR cables you use (or swapped them w/others)?
Could the source of this noise be with the source feeding the ZA3?
Since the recorded noise does not sound MAINS-related, attempting to play some basic grounding tricks with source hardware and/or ZA3 may not lead to any fixes.

Request replacement.

 

[Chrispy]

Hello.

I recenty got Fosi ZA3 stereo amplifier and it works fine with RCA unbalanced connection but when I connect it with XLR balanced connection, it has weird background noise. It gets louder when volume gets higher. I made quick recording of it. Can anyone tell me what may cause this noise and is there any remedy for it or need to ask for replacement under warranty?

Dropbox

www.dropbox.com

Thank you...

So why use the xlr?

 

[decomo]

So why use the xlr?

Because I have two input source and try to reduce box count and using separate preamp or input selector to cater two music sources.

 

[AnalogSteph]

So do you have both connections in use now? I could very well see that giving you ground loop trouble via the unbalanced side if there is any sort of potential difference between the two sources. The RCA side would need galvanic isolation from its ground connection then, wherever that comes in. A diagram of the whole system may be needed to decide on the best course of action (which might involve using a USB isolator, a DAC with Toslink input or even a line isolator).

 

[KL....]

Hello.

I recenty got Fosi ZA3 stereo amplifier and it works fine with RCA unbalanced connection but when I connect it with XLR balanced connection, it has weird background noise. It gets louder when volume gets higher. I made quick recording of it. Can anyone tell me what may cause this noise and is there any remedy for it or need to ask for replacement under warranty?

Dropbox

www.dropbox.com

Thank you...

Do you have the RCA & XLR both connected (at the same time). If yes, try individually connecting them (having only one connected, at a time) and let us know if the weird background noise still occurs, in this case, for either RCA or XLR singularly connected.

Also, if RCA & XLR are both connected (at the same time), try powering/turning off (completely off) the the RCA connected input source/component, and let us know if the weird background noise still occurs for the XLR connected input source/component.

 

[xNORgate]

Because I have two input source and try to reduce box count and using separate preamp or input selector to cater two music sources.

I also have two connected sources - RCAs (SiriusXM)+ XLRs (DAC) - that feed into my desktop ZA3.

Do you have the RCA & XLR both connected (at the same time). If yes, try individually connecting them (having only one connected, at a time) and let us know if the weird background noise still occurs, in this case, for either RCA or XLR singularly connected.

My second ZA3 is also fed with both RCAs + XLRs, with no noise.

I connect it with XLR balanced connection, it has weird background noise.

What specific audio hardware is the source of the ZA3' XLR inputs. Does turning the power off from this source make any difference in this background noise?

*IF you have confirmed the XLR cables have correct pin-outs at both ends and *IF this background noise persists when no XLR cables are physically attached to the ZA3...
Request replacement.