New headphones and USB = background noise

[rmilewsk]

I wasn't sure where to post this so I decided to start here.

 

I have just received the following setup. I've put it all together and it sounds really good.

 

Audez'e LCD-2

 

Burson Headphone Amp 160

 

MHDT Labs Paradisea 3 Non Over Sampling Tube DAC

 

MHDT Labs USBridge USB to SPDIF converter

 

source = Dell XPS via usb.

 

J River software via ASIO

 

 

WHat i'm hearing that I don't like is a constant buzzing in the background. Low in level but always noticeable. Also, whenever I move my mouse, which is also connected via usb, I hear the similar buzzing but at a higher level. The background buzzing changes sound and sometimes sounds like muffled clicks. I've never heard any of these sounds from this computer when playing music through my creative labs soundcard to my speakers.

 

I'm think the problem might be my computer. What options do I have to fix this so I get dead quiet backgrounds?

 

[latitude94941]

Try different usb ports on your computer for the output to the computer. If that doesn't work, start methodically unplugging everything* that is connected to your system. Start with the monitor. Take notes. When you unplug something and the noise disappears, you'll know that you've found the culprit.

 

*Shutting down components as needed for safety and to protect the components.

 

 

 

[sandyk]

By all means try these suggestions, but it is more likely due to poor +5V USB power implementation.

Many people have reported similar problems in other forums.

Laptops are usually the worst offenders.

A USB Isolator will usually fix the problem. It involves cutting the power from the USB port at the receiving end and replacing it with +5V from a standalone power supply.

 

SandyK

 

[coolsax]

I agree with it being a usb power issue. when I got my HRT MSII, i was having issues with static only it was major not just an annoying buzzing, i picked up a self powered usb HUB that has its own wall wart PS and I plugged the MSII into the that and the hub into my laptop. completely eliminated the noise.

 

[rmilewsk]

I have no idea how to "cut the power from the USB port at the receiving end and replacing it with +5V from a standalone power supply"

 

How do I accomplish this?

 

[rmilewsk]

The documentation for the USBridge specifically recommends not using any kind of hubs between the computer and the USBridge. Maybe this is just a recommendation and I can ignore it but I assume they have it there for a reason.

 

From the documentation

 

"The USB Input must be connected directly to the USB interface of a coomputer. Function can be disrupted when a USB hub is in the connection line"

 

[kumakuma]

"I have no idea how to "cut the power from the USB port at the receiving end and replacing it with +5V from a standalone power supply""

 

I think the OP meant that this what a USB isolator does, not what you want to do yourself.

 

I think your quickest solution is to try connecting the DAC through a USB hub rather than to one of the USB ports on the Dell.

 

K

 

[kumakuma]

Forget my last comment. Our posts crossed.

 

You could always try and see if it works through a hub though. Easy to get one of these devices... and easy to return if it doesn't do the trick.

 

K

 

[coolsax]

i didn't know that it wasn't recommended, but i have no issues with running the MSII through the HUB at all.

 

 

[One and a half]

is sometimes, the laptop's power supply. The same noises as the OP describes appeared on an Asus and Sony. By running the laptops from the internal battery knocked the noise dead.

 

Long term, that's not going to work. Anything that breaks the "connection" to the noise, such as a powered hub may do the trick.

 

Another possibility is to use a 3rd party power supply, one that proclaims low noise emissions, and that is a quest on its own.

 

If you can avoid the analog cabling, well away from the laptop's power supply would also help. I tried an isolation transformer, but the noise is emitted and the transformer didn't help.

 

[sandyk]

If you guys were in to DIY, you could construct something like at the attached link.

http://www.altronics.com.au/index.asp?area=item&id=K2910

I have also previously posted about a full on non commercial DIY +5V Linear PSU that I use for my Corsair Voyager GT USB sticks.The project was posted in another forum.

Many people would not even be aware of the degradation that crappy SMPS +5V from a USB port can cause with USB audio, unless you play the audio through a revealing system.

Just because you may not hear mouse clicks and keyboard clicks through USB audio, does not mean that poorly implemented SMPS +5V USB power isn't degrading it.

SandyK

 

[rmilewsk]

I'm sorry if I didn't mention it but I am not running from a laptop I'm running this from a desktop computer.

 

As an update. I've found no way to eliminate the noise. I've purchased a separate USB 2.0 card to use just for hooking up the USB and I will see how that works.

 

Any other suggestions are appreciated.

 

[mleghorn]

I suspect the problem is introduced before your USB connection, i.e. in the computer. I noticed you're using an ASIO driver. Is that necessary? There is a standard USB audio device driver for Windows (which I use all the time for my DAC, and it works great). It doesn't do much, other than route the digital to your USB. I suggest, then, temporarily uninstalling whatever software you're using for your USB drivers, and plugging your external device (i.e. DAC) into your computer's USB. It should be plug and play, and select the standard USB driver.