amplifier Static Noise on Power Amplifier in Aux Input - Is It Normal To Have?

[Sovon Halder]

So either my ears got hyper sensitive somehow to nuances in audio frequency or my WXA-50 got damaged. Should an amp produce static noise of any kind, on passive speakers?

My Desk Setup: Mac Mini M1 + WXA-50 + 3020i Pair (with 3.5mm to RCA & Nakamichi banana plugs w/ 12 gauge spool)

 

I quite literally HEARD the static noise, for the first time today. I thought it was an outside noise and ignored it at first, but then when I went close to the speakers, turns out there was indeed a noise coming out of the twitter, on both channels. It boggles my mind as to why this is the first time I'm listening to the static. I've been using this since August 2020 and at the time I was in a very quiet place too, compared to where I am right now. But never before; weird. So, here are things that I observed, and did to find out why it might be happening (while playing nothing).

1. It's barely audible from normal desktop sitting position but the noise is there; if I'm in a quiet room and wxa50 has -10db or higher, you'll hear the noise. Specially if you switch to bluetooth from aux, you'll feel the speakers suddenly went quietER.

2. The noise increases as I turn up the volume on the wxa-50 and it's not the aux-rca cable either cause I unplugged the aux cable from mac mini. Interestingly, the noise is tripled when there is nothing connected in the RCA input. But bluetooth input the noise is significantly reduced, like 1/3rd. And for optical it's the quietest (like almost non existent noise) So it's not the fault of the speakers either I guess.

3. I turned off every electrical equipment including lights in my house to see if this issue is due to an electrical fault somewhere else. But the noise remains. For the past 5 months, I've noticed that sometimes when a fan or light in another room is turned off, there is a noticeable crack/pop in my speaker. Not exceptionally loud but loud enough to startle you when you are sitting alone in a quiet room.

The fact that the speakers are not dead silent even when my computer is turned off is bothering me. Again, the noise isn't too much to interfere with daily tasks but with aux input it's really annoying me, and I can't figure out why I haven't noticed this before. If I touch the 3.5mm end of the 3.5mm to rcacable (rca connected to the amp), there is a strong tingling/vibrations.
I'm using an outlet from the wall that is grounded and using a Honeywell surge protector that shows "Protected" in a green dot. Despite that, I discovered this noise today.

Even right now, I have the max volume on WXA-50, and nothing playing from the computer side - there is a significant hiss / static noise going on.

 

What is this? And how do I get rid of this?

[GroundRod]

Do you have a monitor attached?

[Sovon Halder]

On 1/16/2021 at 10:30 PM, GroundRod said:

Do you have a monitor attached?

I have a pair of 3020i Bookshelf speakers attached to the amp - if you are referring to the audio side, and I have a 4K LG monitor running right beside the amp, connected to the same mac mini feeding the amp - if you are referring to the display side.

[Ahoy Hoy]

On 1/15/2021 at 6:15 AM, Sovon Halder said:

1. I turned off every electrical equipment including lights in my house to see if this issue is due to an electrical fault somewhere else. But the noise remains. For the past 5 months, I've noticed that sometimes when a fan or light in another room is turned off, there is a noticeable crack/pop in my speaker. Not exceptionally loud but loud enough to startle you when you are sitting alone in a quiet room.

100% a earth problem. The fact that other electrical devices can affect guarantees that in my mind.
The cause can vary from certain electrical equipment or poor wiring.
I cant think of a way to solve the problem completely. But I may be able to help with the Aux line.

If you search for "Aux ground isolation" and "RCA ground isolation" you should get things which look like this

They isolate the ground between devices it may help but it also may not solve the problem. It will most likely make the Aux inputs sound like the optical input.

I hope that helps. But the more I read your problem the more it sound like a problem in the house power and the only solution I can think of is too dangerous to suggest.

[Sovon Halder]

On 1/19/2021 at 11:49 PM, Ahoy Hoy said:

It will most likely make the Aux inputs sound like the optical input.

Is that good or bad? (Can you please answer objectively, as in someone who prefers audio the way it was intended to be heard by the artist to other acoustic flares different inputs/connections might add)

 

I ordered a D10s to use it as a USB Bridge. I've heard good things about it from Darko Audio.

My streaming amp WXA-50 has a good DAC I think (?). I hope the quality increases with an optical toslink connection, compared to my current setup.