Noise problems with new Topping D10

[cipa]

Hey guys, after a LOT of research I bought the Topping D10 + JDS Atom to be used with my Sennheiser HD650 and Krk Rokit 5 Speakers. My source is a desktop computer.

The thing is I'm having a terrible time trying to understand why I am getting so much noise when using the speakers. I got noises that are linked to the usage of the computer, like I can hear through the speakers when I'm scrolling down a webpage and things like that. When using the DAC with a batteryu powered laptop, there is no noise, so I'm thinking it's some kind of ground loop from my desktop.

Are there good ways to get rid of this problem? After searching I've found a device that promisses to stop the noise (iFi Audio iDefender 3.0), but it costs almost as much as the DAC I bought, so it does not seems really worth. I found something called adum4160 but it uses USB1.1, which would not be compatible with Hires audio files.

Those noises are driving me insane, I would appreciate any help!

 

[matt3421]

i had the same problem with my d10 and kali speakers. had to sell the d10 for something with optical input

 

[heic1502a]

The problem is most likely a ground loop in your setup.

Your desktop have a ground connection, and I assume your powered speakers also have a ground connection, and the desktop is connected to the speakers through the DAC and amp. There are two grounds in the system and thus a ground loop is formed.

To test if you have this exact problem, you can use a laptop as the input of your D10 (do not plug in the charger of the laptop, only use the internal battery), and if the noise is gone, that means you indeed have a ground loop problem.

To solve this problem you will need to break the ground loop, and there are many ways to do it.

• You can get another DAC with optical input, and use it between the D10 and Atom, this is the best way IMO, though not the cheapest.
• Ifi have a product called iDefender, that should solve the problem (when used together with their iPower), but I have not tested it myself.
• There are many ground loop isolators on amazon, they are pretty cheap and will break the ground loop, but may change the frequency response of your output (I own one and the difference in sound is not really noticeable to me), so it's a trade off.
• There are usb Isolators on amazon, they will also theoretically break the ground loop, but I have not tried one.
• The one method you shouldn't try is lifting the ground on your speakers by using a ground lifting plug, this might seem like the cheapest and easiest way to break the ground loop, but its really dangerous to use your speakers without grounding.

 

[March Audio]

The problem is most likely a ground loop in your setup.

Your desktop have a ground connection, and I assume your powered speakers also have a ground connection, and the desktop is connected to the speakers through the DAC and amp. There are two grounds in the system and thus a ground loop is formed.

To test if you have this exact problem, you can use a laptop as the input of your D10 (do not plug in the charger of the laptop, only use the internal battery), and if the noise is gone, that means you indeed have a ground loop problem.

To solve this problem you will need to break the ground loop, and there are many ways to do it.

• You can get another DAC with optical input, and use it between the D10 and Atom, this is the best way IMO, though not the cheapest.
• Ifi have a product called iDefender, that should solve the problem (when used together with their iPower), but I have not tested it myself.
• There are many ground loop isolators on amazon, they are pretty cheap and will break the ground loop, but may change the frequency response of your output (I own one and the difference in sound is not really noticeable to me), so it's a trade off.
• There are usb Isolators on amazon, they will also theoretically break the ground loop, but I have not tried one.
• The one method you shouldn't try is lifting the ground on your speakers by using a ground lifting plug, this might seem like the cheapest and easiest way to break the ground loop, but its really dangerous to use your speakers without grounding.

This, but I dont see a reason for a gnd isolator to otherwise change the sound (freq response). The data has not changed.

I wasnt aware of this iDefender. Might do a bit more research on its operation and then give one a whizz see if it does properly isolate. Unless it re-generates its own isolated 5V, plugging in an external power brick could still create issues.

 

[heic1502a]

This, but I dont see a reason for a gnd isolator to otherwise change the sound (freq response). The data has not changed.

I wasnt aware of this iDefender. Might do a bit more research on its operation and then give one a whizz see if it does properly isolate. Unless it re-generates its own isolated 5V, plugging in an external power brick could still create issues.

The ground loop isolator I used is like this one in the video:

If I'm correct, the device is basically an AC transformer, and since the main components are inductors, I suspect the frequency responce of the device won't be flat.
Edit: I was a little unclear about the naming, I think it's more appropriate to call it audio isolator instead of ground loop isolator. There is another product called Hum X that works by isolating the ground connection, which shouldn't affect the sound at all, but some people say it's unsafe to use.

Also I don't know how the iDefender works either. Judging from the product description and reviews, it seems to be suited for ground loop problems, I hope someone can figure out how it works.

 

[March Audio]

The ground loop isolator I used is like this one in the video:

If I'm correct, the device is basically an AC transformer, and since the main components are inductors, I suspect the frequency responce of the device won't be flat.

Also I don't know how the iDefender works either. Judging from the product description and reviews, it seems to be suited for ground loop problems, I hope someone can figure out how it works.

Oh sure that probably wont be flat because its in line with/carrying the actual audio signal. A USB isolator on the other hand operates on the USB data and 5 volt power rail. So as long as the data gets through with a reasonable quality eye signal there will be no change.

 

[Archmage]

That HumX device claims it isn't a ground lift, but I think it's an anti-parallel diode setup that gives a low-level "lift." You can probably find schematics of almost exactly this type of device and build it inexpensively.

It should work for its intended purpose, but I'll leave it to the more knowledgeable to determine whether it's actually an acceptable solution.

Edit: Looks like the HumX is probably a bit more complicated than that, and some DIY circuits are using a bridge rectifier.
https://sound-au.com/earthing.htm - looks like this Rod Elliott article is the source of that info