Groundloop noise/ buzzing nvr speaker

[Cctvrole]

Hi there

I bought the Adastra AH25 horn speaker for my Dahua nvr and as soon as I connected it to power it gives me a groundloop noice(I think it's called?).

And someone told me that I should just connect it to aa singel power Socket. But the problem is that it's going to be installed in a outdoor box with several other devices such as the NVR, 4g router etc so that's not possible and I can't figure out how to fix this problem to make me get rid of this noice.

I would be more then thankful if anyone could tell me how to fix this. I'm keep getting two different noices one when it's connected to the NVR and the other one ( I couldn't uploaded getting errors) is the same sound but like high pitched
View attachment 20210928_163734.mp4

 

[tigerwillow1]

I don't know what a groundloop notice is, but anyway, finding and fixing the ground loop is the best solution. But if that's not going to happen you can try a ground loop isolator which is usually just a 1:1 transformer, example:

https://www.bestbuy.com/site/metra-ground-loop-isolator-black/9855136.p?skuId=9855136

.

 

[sebastiantombs]

I'd suggest a good, transformer based, power supply for the speker instead of a cheap switching power supply.

 

[Cctvrole]

I'd suggest a good, transformer based, power supply for the speker instead of a cheap switching power supply.

They suggested a simple 12v adapter for the speaker from them that I got. After talking to them they recommended me to connect it to a 12v battery and they didn't have a better solution. So many 12v adapters out their can't figure out which one I should get.

 

[sebastiantombs]

You're looking for something like this -

Amazon.com

 

[TonyR]

Although the specs here say that power and signal grounds are common, you might want to hook it up as it says, with yellow for audio signal and green for ground:

 

[Cctvrole]

Although the specs here say that power and signal grounds are common, you might want to hook it up as it says, with yellow for audio signal and green for ground:

View attachment 103984

Mine is diffrent.

Yellow is for signal
White is ground
Black is ground
Red doesn't have anything

 

[Cctvrole]

 

[TonyR]

Red doesn't have anything

Then how is the speaker's amplifier powered????
Your image states the red is for +12 VDC.

 

[TonyR]

More info...

It appears the PDF specs and image I posted were from 2018 and from a speaker vendor; the specs here are from the manufacturer (AVSL), are dated 2019 and concur with your speaker's color code.

HOWEVER...in both specs the red must be connected to +12 VDC to power the speaker's amplifier.

EDIT: Although both specs imply with the reference number of "UK" that they are for the UK, it's likely someone decided to change the color code to a more acceptable color code. In DC circuits, wherein red is generally DC + (positive) and black is DC - (negative) and in AC circuits black is generally AC "hot" side, white is AC neutral and green is earth ground (at least for U.S.A. AC circuits). IIRC, in the UK and in Europe AC circuits, AC hot is brown, AC neutral is blue and earth ground is yellow with green stripe......it can be confusing and the vendor should NEVER have used the colors a DC circuit that he as was shown in the 2018 specs.

 

[Cctvrole]

More info...

It appears the PDF specs and image I posted were from 2018 and from a speaker vendor; the specs here are from the manufacturer (AVSL), are dated 2019 and concur with your speaker's color code.

HOWEVER...in both specs the red must be connected to +12 VDC to power the speaker's amplifier.

Thats what I have done.

Red and black for power

And on the Rca I put yellow(signal) on + side and White (GND) on - side

 

[TonyR]

Thats what I have done.

Red and black for power

And on the Rca I put yellow(signal) on + side and White (GND) on - side

OK, in your post # & above you stated "....Red doesn't have anything".

Assuming you have it connected as in your image and your 12VDC power supply is as required and good then it should work, unless speaker is faulty.

 

[sebastiantombs]

Can you "ohm out" the resistance between the white and black wires? If you can do that twice, reversing the polarity of the ohm meter and the wires of the speaker.

 

[TonyR]

BTW, how far away is the speaker from the NVR ?

 

[IPCamer]

@Cctvrole Did you test your speaker with open input, the plug not connected, or already connected to your nvr?
What if you short the input , so directly connect the yellow and white wire together, is the hum then less or gone? If not, then the power supply used, is not clean enough on the DC power lines. Try an other power supply for the speaker to check for hum.